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Question 1
Correct
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An 80-year-old man who frequently drinks alcohol presents to his doctor with symptoms of productive cough, fever, and chills. Upon examination, a chest x-ray reveals a distinct cavity in the right lower lobe with an air-fluid level. The patient's sputum is sent for culture and sensitivity, and he is prescribed clindamycin.
After ten days, the patient reports experiencing watery diarrhea 3-4 times a day and abdominal pain. He has not experienced any fever or weight loss, and his vital signs are normal. What is the initial medication recommended for his condition?Your Answer: Vancomycin
Explanation:The preferred antibiotic for treating C. difficile infection is oral vancomycin. However, in the case of a patient with clinical features and radiological findings indicative of a lung abscess, who also has a history of alcohol consumption that increases the risk of aspiration and lung abscesses, clindamycin was used as a treatment. Unfortunately, this led to the development of a C. difficile infection, which can be confusing when considering the antibiotics involved in causing and treating the infection.
Clostridium difficile is a type of bacteria that is commonly found in hospitals. It produces a toxin that can damage the intestines and cause a condition called pseudomembranous colitis. This bacteria usually develops when the normal gut flora is disrupted by broad-spectrum antibiotics, with second and third generation cephalosporins being the leading cause. Other risk factors include the use of proton pump inhibitors. Symptoms of C. difficile infection include diarrhea, abdominal pain, and a raised white blood cell count. The severity of the infection can be determined using the Public Health England severity scale.
To diagnose C. difficile infection, a stool sample is tested for the presence of the C. difficile toxin. Treatment involves reviewing current antibiotic therapy and stopping antibiotics if possible. For a first episode of infection, oral vancomycin is the first-line therapy for 10 days, followed by oral fidaxomicin as second-line therapy and oral vancomycin with or without IV metronidazole as third-line therapy. Recurrent infections may require different treatment options, such as oral fidaxomicin within 12 weeks of symptom resolution or oral vancomycin or fidaxomicin after 12 weeks of symptom resolution. In life-threatening cases, oral vancomycin and IV metronidazole may be used, and surgery may be considered with specialist advice. Other therapies, such as bezlotoxumab and fecal microbiota transplant, may also be considered for preventing recurrences in certain cases.
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This question is part of the following fields:
- Gastrointestinal System
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Question 2
Correct
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A 36-year-old woman is found to have an aggressive caecal adenocarcinoma. Her sister passed away from the same disease at 39 years of age. Her mother died from endometrial cancer at the age of 42. What genetic abnormality is the most probable cause of this family's cancer history?
Your Answer: Mutation of mismatch repair genes
Explanation:Microsatellite instability of DNA repair genes causes Lynch syndrome, which is identified by the presence of aggressive colon cancer on the right side and endometrial cancer.
Colorectal cancer can be classified into three types: sporadic, hereditary non-polyposis colorectal carcinoma (HNPCC), and familial adenomatous polyposis (FAP). Sporadic colon cancer is believed to be caused by a series of genetic mutations, including allelic loss of the APC gene, activation of the K-ras oncogene, and deletion of p53 and DCC tumor suppressor genes. HNPCC, which is an autosomal dominant condition, is the most common form of inherited colon cancer. It is caused by mutations in genes involved in DNA mismatch repair, leading to microsatellite instability. The most common genes affected are MSH2 and MLH1. Patients with HNPCC are also at a higher risk of other cancers, such as endometrial cancer. The Amsterdam criteria are sometimes used to aid diagnosis of HNPCC. FAP is a rare autosomal dominant condition that leads to the formation of hundreds of polyps by the age of 30-40 years. It is caused by a mutation in the APC gene. Patients with FAP are also at risk of duodenal tumors. A variant of FAP called Gardner’s syndrome can also feature osteomas of the skull and mandible, retinal pigmentation, thyroid carcinoma, and epidermoid cysts on the skin. Genetic testing can be done to diagnose HNPCC and FAP, and patients with FAP generally have a total colectomy with ileo-anal pouch formation in their twenties.
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This question is part of the following fields:
- Gastrointestinal System
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Question 3
Correct
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A 67-year-old man visits his GP after discovering a lump in his groin subsequent to moving houses. He reports no other symptoms such as abdominal pain or changes in bowel habits. The patient can push the lump back in, but it returns when he coughs. The GP suspects a hernia and upon examination, locates the hernia's neck, which is superior and medial to the pubic tubercle. The GP reduces the lump, applies pressure to the midpoint of the inguinal ligament, and asks the patient to cough, causing the lump to reappear. The patient has no history of surgery. What is the most probable cause of the patient's groin lump?
Your Answer: Direct inguinal hernia
Explanation:Based on the location of the hernia, which is superior and medial to the pubic tubercle, it is likely an inguinal hernia rather than a femoral hernia which would be located inferior and lateral to the pubic tubercle.
If the hernia is a direct inguinal hernia, it would have entered the inguinal canal by passing through the posterior wall of the canal instead of the deep inguinal ring. Therefore, it would reappear despite pressure on the deep inguinal ring.
On the other hand, if the hernia is an indirect inguinal hernia, it would have entered the inguinal canal through the deep inguinal ring and exited at the superficial inguinal ring. In this case, it would not reappear if the deep inguinal ring was occluded.
Since the hernia is reducible, it is not incarcerated.
Lastly, a spigelian hernia occurs when there is a herniation through the spigelian fascia, which is located along the semilunar line.
Understanding Inguinal Hernias
Inguinal hernias are the most common type of abdominal wall hernias, with 75% of cases falling under this category. They are more prevalent in men, with a 25% lifetime risk of developing one. The main symptom is a lump in the groin area, which disappears when pressure is applied or when the patient lies down. Discomfort and aching are also common, especially during physical activity. However, severe pain is rare, and strangulation is even rarer.
The traditional classification of inguinal hernias into indirect and direct types is no longer relevant in clinical management. Instead, the current consensus is to treat medically fit patients, even if they are asymptomatic. A hernia truss may be an option for those who are not fit for surgery, but it has limited use in other patients. Mesh repair is the preferred method, as it has the lowest recurrence rate. Unilateral hernias are usually repaired through an open approach, while bilateral and recurrent hernias are repaired laparoscopically.
After surgery, patients are advised to return to non-manual work after 2-3 weeks for open repair and 1-2 weeks for laparoscopic repair. Complications may include early bruising and wound infection, as well as late chronic pain and recurrence. It is important to seek medical attention if any of these symptoms occur.
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This question is part of the following fields:
- Gastrointestinal System
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Question 4
Correct
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A 67-year-old male with long standing chronic obstructive pulmonary disease (COPD) presents to the emergency department (ED) with shortness of breath over the last 2 hours and wheezing. On examination, he is cyanosed, has a third heart sound present and has widespread wheeze on auscultation. The emergency doctor also notices hepatomegaly which was not present 10 days ago when he was in the ED for a moderative exacerbation of COPD.
What is the likely cause of the newly developed hepatomegaly in this 67-year-old male with chronic obstructive pulmonary disease?Your Answer: Cor pulmonale
Explanation:The cause of the patient’s hepatomegaly is likely subacute onset cor pulmonale, which is right sided heart failure secondary to COPD. This is supported by the presence of shortness of breath, cyanosis, and a third heart sound. Left sided heart failure is unlikely to be the cause of his symptoms and hepatomegaly. While ascites can be a complication of right sided heart failure and portal hypertension, it does not cause hepatomegaly. Cirrhosis and liver cancer are also unlikely causes given the patient’s presentation, which is more consistent with a cardiorespiratory issue.
Understanding Hepatomegaly and Its Common Causes
Hepatomegaly refers to an enlarged liver, which can be caused by various factors. One of the most common causes is cirrhosis, which can lead to a decrease in liver size in later stages. In this case, the liver is non-tender and firm. Malignancy, such as metastatic spread or primary hepatoma, can also cause hepatomegaly. In this case, the liver edge is hard and irregular. Right heart failure can also lead to an enlarged liver, which is firm, smooth, and tender. It may even be pulsatile.
Aside from these common causes, hepatomegaly can also be caused by viral hepatitis, glandular fever, malaria, abscess (pyogenic or amoebic), hydatid disease, haematological malignancies, haemochromatosis, primary biliary cirrhosis, sarcoidosis, and amyloidosis.
Understanding the causes of hepatomegaly is important in diagnosing and treating the underlying condition. Proper diagnosis and treatment can help prevent further complications and improve overall health.
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This question is part of the following fields:
- Gastrointestinal System
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Question 5
Incorrect
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A 30-year-old man presents with an inguinal hernia. What structure needs to be divided during open surgery to access the inguinal canal?
Your Answer: Rectus abdominis
Correct Answer: External oblique aponeurosis
Explanation:What forms the front wall of the inguinal canal? The external oblique aponeurosis forms the front wall. To access the canal and perform a hernia repair, the aponeurosis is divided. The posterior wall is made up of the transversalis fascia and conjoint tendons, which are not typically cut to gain entry to the inguinal canal.
The External Oblique Muscle: Anatomy and Function
The external oblique muscle is one of the three muscles that make up the anterolateral aspect of the abdominal wall. It is the outermost muscle and plays an important role in supporting the abdominal viscera. The muscle originates from the outer surfaces of the lowest eight ribs and inserts into the anterior two-thirds of the outer lip of the iliac crest. The remaining portion of the muscle becomes the aponeurosis, which fuses with the linea alba in the midline.
The external oblique muscle is innervated by the ventral rami of the lower six thoracic nerves. Its main function is to contain the abdominal viscera and raise intra-abdominal pressure. Additionally, it can move the trunk to one side. The aponeurosis of the external oblique muscle also forms the anterior wall of the inguinal canal, which is an important anatomical landmark in the groin region.
Overall, the external oblique muscle is a crucial component of the abdominal wall and plays an important role in maintaining the integrity of the abdominal cavity. Its unique anatomy and function make it an important muscle for both movement and protection of the internal organs.
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This question is part of the following fields:
- Gastrointestinal System
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Question 6
Correct
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A 75-year-old woman comes in with a femoral hernia. What structure makes up the lateral boundary of the femoral canal?
Your Answer: Femoral vein
Explanation:The purpose of the canal is to facilitate the natural expansion of the femoral vein located on its side.
Understanding the Femoral Canal
The femoral canal is a fascial tunnel located at the medial aspect of the femoral sheath. It contains both the femoral artery and femoral vein, with the canal lying medial to the vein. The borders of the femoral canal include the femoral vein laterally, the lacunar ligament medially, the inguinal ligament anteriorly, and the pectineal ligament posteriorly.
The femoral canal plays a significant role in allowing the femoral vein to expand, which facilitates increased venous return to the lower limbs. However, it can also be a site of femoral hernias, which occur when abdominal contents protrude through the femoral canal. The relatively tight neck of the femoral canal places these hernias at high risk of strangulation, making it important to understand the anatomy and function of this structure. Overall, understanding the femoral canal is crucial for medical professionals in diagnosing and treating potential issues related to this area.
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This question is part of the following fields:
- Gastrointestinal System
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Question 7
Correct
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A 65-year-old woman visits her GP complaining of altered bowel habit for the past 2 months. She denies experiencing melaena or fresh rectal blood. The patient has a medical history of type 2 diabetes mellitus and breast cancer, which has been in remission for 2 years. She consumes 14 units of alcohol per week.
During abdominal palpation, the liver edge is palpable and nodular, descending below the right costal margin. There is no presence of shifting dullness.
What is the probable cause of the patient's examination findings?Your Answer: Liver metastases
Explanation:If a patient has hepatomegaly and a history of malignancy, it is likely that they have liver metastases. The nodular edge of the liver, along with the patient’s history of breast cancer, is a cause for concern regarding cancer recurrence. Acute alcoholic hepatitis, Budd-Chiari syndrome, and non-alcoholic steatohepatitis are less likely causes in this scenario.
Understanding Hepatomegaly and Its Common Causes
Hepatomegaly refers to an enlarged liver, which can be caused by various factors. One of the most common causes is cirrhosis, which can lead to a decrease in liver size in later stages. In this case, the liver is non-tender and firm. Malignancy, such as metastatic spread or primary hepatoma, can also cause hepatomegaly. In this case, the liver edge is hard and irregular. Right heart failure can also lead to an enlarged liver, which is firm, smooth, and tender. It may even be pulsatile.
Aside from these common causes, hepatomegaly can also be caused by viral hepatitis, glandular fever, malaria, abscess (pyogenic or amoebic), hydatid disease, haematological malignancies, haemochromatosis, primary biliary cirrhosis, sarcoidosis, and amyloidosis.
Understanding the causes of hepatomegaly is important in diagnosing and treating the underlying condition. Proper diagnosis and treatment can help prevent further complications and improve overall health.
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This question is part of the following fields:
- Gastrointestinal System
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Question 8
Correct
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An 80-year-old woman visits her doctor with complaints of moderate upper abdominal pain that is slightly relieved by eating. Despite taking ibuprofen, she has not experienced any relief. The doctor suspects a duodenal peptic ulcer and schedules an oesophagogastroduodenoscopy (OGD). Based on the location of the ulcer, which organ is derived from the same embryological region of the gut?
Your Answer: Oesophagus
Explanation:The major papilla located in the 2nd part of the duodenum marks the division between the foregut and the midgut, with the foregut encompassing structures from the mouth to the 2nd part of the duodenum where peptic ulcers are commonly found. It should be noted that the kidneys are not derived from gut embryology, but rather from the ureteric bud.
The Three Embryological Layers and their Corresponding Gastrointestinal Structures and Blood Supply
The gastrointestinal system is a complex network of organs responsible for the digestion and absorption of nutrients. During embryonic development, the gastrointestinal system is formed from three distinct layers: the foregut, midgut, and hindgut. Each layer gives rise to specific structures and is supplied by a corresponding blood vessel.
The foregut extends from the mouth to the proximal half of the duodenum and is supplied by the coeliac trunk. The midgut encompasses the distal half of the duodenum to the splenic flexure of the colon and is supplied by the superior mesenteric artery. Lastly, the hindgut includes the descending colon to the rectum and is supplied by the inferior mesenteric artery.
Understanding the embryological origin and blood supply of the gastrointestinal system is crucial in diagnosing and treating gastrointestinal disorders. By identifying the specific structures and blood vessels involved, healthcare professionals can better target their interventions and improve patient outcomes.
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This question is part of the following fields:
- Gastrointestinal System
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Question 9
Correct
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A man in his 50s is diagnosed with pernicious anaemia. What is the probable cause for this condition?
Your Answer: Autoimmune antibodies to parietal cells
Explanation:The destruction of gastric parietal cells, often due to autoimmune factors, is a primary cause of pernicious anaemia. In some cases, mixed patterns may be present and further diagnostic assessment may be necessary, particularly in instances of bacterial overgrowth.
Pernicious anaemia is a condition that results in a deficiency of vitamin B12 due to an autoimmune disorder affecting the gastric mucosa. The term pernicious refers to the gradual and subtle harm caused by the condition, which often leads to delayed diagnosis. While pernicious anaemia is the most common cause of vitamin B12 deficiency, other causes include atrophic gastritis, gastrectomy, and malnutrition. The condition is characterized by the presence of antibodies to intrinsic factor and/or gastric parietal cells, which can lead to reduced vitamin B12 absorption and subsequent megaloblastic anaemia and neuropathy.
Pernicious anaemia is more common in middle to old age females and is associated with other autoimmune disorders such as thyroid disease, type 1 diabetes mellitus, Addison’s, rheumatoid, and vitiligo. Symptoms of the condition include anaemia, lethargy, pallor, dyspnoea, peripheral neuropathy, subacute combined degeneration of the spinal cord, neuropsychiatric features, mild jaundice, and glossitis. Diagnosis is made through a full blood count, vitamin B12 and folate levels, and the presence of antibodies.
Management of pernicious anaemia involves vitamin B12 replacement, usually given intramuscularly. Patients with neurological features may require more frequent doses. Folic acid supplementation may also be necessary. Complications of the condition include an increased risk of gastric cancer.
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This question is part of the following fields:
- Gastrointestinal System
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Question 10
Correct
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A 25-year-old male patient complains of mucous passage and diarrhea, leading to a suspicion of ulcerative colitis. Which of the following is not commonly associated with this disease?
Your Answer: Episodes of large bowel obstruction during acute attacks
Explanation:Crohn’s disease is associated with a higher risk of colorectal cancer compared to the general population, particularly if the disease has been present for over 20 years. Granulomas are a common feature of Crohn’s disease. The disease typically affects the rectum and can spread upwards, and contact bleeding may occur. In cases of longstanding ulcerative colitis, there may be crypt atrophy and metaplasia/dysplasia.
Understanding Ulcerative Colitis
Ulcerative colitis is a type of inflammatory bowel disease that causes inflammation in the rectum and spreads continuously without going beyond the ileocaecal valve. It is most commonly seen in people aged 15-25 years and 55-65 years. The symptoms of ulcerative colitis are insidious and intermittent, including bloody diarrhea, urgency, tenesmus, abdominal pain, and extra-intestinal features. Diagnosis is done through colonoscopy and biopsy, but in severe cases, a flexible sigmoidoscopy is preferred to avoid the risk of perforation. The typical findings include red, raw mucosa that bleeds easily, widespread ulceration with preservation of adjacent mucosa, and inflammatory cell infiltrate in lamina propria. Extra-intestinal features of inflammatory bowel disease include arthritis, erythema nodosum, episcleritis, osteoporosis, uveitis, pyoderma gangrenosum, clubbing, and primary sclerosing cholangitis. Ulcerative colitis is linked with sacroiliitis, and a barium enema can show the whole colon affected by an irregular mucosa with loss of normal haustral markings.
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This question is part of the following fields:
- Gastrointestinal System
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Question 11
Incorrect
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A 29-year-old man is diagnosed with pleomorphic adenoma and requires surgical resection. During the procedure, which of the following structures is least likely to be encountered in the resection of the parotid gland?
Your Answer: Retromandibular vein
Correct Answer: Mandibular nerve
Explanation:The parotid gland is traversed by several important structures, including the facial nerve and its branches, the external carotid artery and its branches (such as the maxillary and superficial temporal arteries), the retromandibular vein, and the auriculotemporal nerve. However, the mandibular nerve is located at a safe distance from the gland. The maxillary vein joins with the superficial temporal vein to form the retromandibular vein, which passes through the parotid gland. Damage to the auriculotemporal nerve during a parotidectomy can result in regrowth that attaches to sweat glands, leading to gustatory sweating (Freys Syndrome). The marginal mandibular branch of the facial nerve is also associated with the parotid gland.
The parotid gland is located in front of and below the ear, overlying the mandibular ramus. Its salivary duct crosses the masseter muscle, pierces the buccinator muscle, and drains adjacent to the second upper molar tooth. The gland is traversed by several structures, including the facial nerve, external carotid artery, retromandibular vein, and auriculotemporal nerve. The gland is related to the masseter muscle, medial pterygoid muscle, superficial temporal and maxillary artery, facial nerve, stylomandibular ligament, posterior belly of the digastric muscle, sternocleidomastoid muscle, stylohyoid muscle, internal carotid artery, mastoid process, and styloid process. The gland is supplied by branches of the external carotid artery and drained by the retromandibular vein. Its lymphatic drainage is to the deep cervical nodes. The gland is innervated by the parasympathetic-secretomotor, sympathetic-superior cervical ganglion, and sensory-greater auricular nerve. Parasympathetic stimulation produces a water-rich, serous saliva, while sympathetic stimulation leads to the production of a low volume, enzyme-rich saliva.
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This question is part of the following fields:
- Gastrointestinal System
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Question 12
Correct
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A 50-year-old male has been diagnosed with carcinoma of the head of the pancreas. He has reported that his stool is sticking to the toilet bowl and not flushing away. Which enzyme deficiency is most likely causing this issue?
Your Answer: Lipase
Explanation:Steatorrhoea, characterized by pale and malodorous stools that are hard to flush, is primarily caused by a deficiency in lipase.
Pancreatic cancer is a type of cancer that is often diagnosed late due to its non-specific symptoms. The majority of pancreatic tumors are adenocarcinomas and are typically found in the head of the pancreas. Risk factors for pancreatic cancer include increasing age, smoking, diabetes, chronic pancreatitis, hereditary non-polyposis colorectal carcinoma, and mutations in the BRCA2 and KRAS genes.
Symptoms of pancreatic cancer can include painless jaundice, pale stools, dark urine, and pruritus. Courvoisier’s law states that a palpable gallbladder is unlikely to be due to gallstones in the presence of painless obstructive jaundice. However, patients often present with non-specific symptoms such as anorexia, weight loss, and epigastric pain. Loss of exocrine and endocrine function can also occur, leading to steatorrhea and diabetes mellitus. Atypical back pain and migratory thrombophlebitis (Trousseau sign) are also common.
Ultrasound has a sensitivity of around 60-90% for detecting pancreatic cancer, but high-resolution CT scanning is the preferred diagnostic tool. The ‘double duct’ sign, which is the simultaneous dilatation of the common bile and pancreatic ducts, may be seen on imaging.
Less than 20% of patients with pancreatic cancer are suitable for surgery at the time of diagnosis. A Whipple’s resection (pancreaticoduodenectomy) may be performed for resectable lesions in the head of the pancreas, but side-effects such as dumping syndrome and peptic ulcer disease can occur. Adjuvant chemotherapy is typically given following surgery, and ERCP with stenting may be used for palliation.
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This question is part of the following fields:
- Gastrointestinal System
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Question 13
Correct
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A patient arrives at the emergency department with complaints of abdominal pain in the right iliac fossa. Upon palpation, the patient experiences pain in the right iliac fossa when pressure is applied to the left iliac fossa. What is the term used to describe this sign?
Your Answer: Rovsing's sign
Explanation:Rovsing’s sign is a diagnostic indicator of appendicitis, characterized by pain in the right lower abdomen when the left lower abdomen is palpated. The Psoas sign is another indicator of appendicitis, where flexing the right hip causes irritation of the psoas muscle. The Obturator sign is also a sign of appendicitis, where discomfort is felt in the obturator internus muscle when both the hip and knees are flexed to 90 degrees. However, McBurney’s sign, which refers to pain in the right lower abdomen 2/3 of the way from the umbilicus to the right anterior superior iliac spine, is not a reliable indicator of appendicitis.
Acute appendicitis is a common condition that requires surgery and can occur at any age, but is most prevalent in young people aged 10-20 years. The pathogenesis of acute appendicitis involves lymphoid hyperplasia or a faecolith, which leads to obstruction of the appendiceal lumen. This obstruction causes gut organisms to invade the appendix wall, resulting in oedema, ischaemia, and possibly perforation.
The most common symptom of acute appendicitis is abdominal pain, which is typically peri-umbilical and radiates to the right iliac fossa due to localised peritoneal inflammation. Other symptoms include mild pyrexia, anorexia, and nausea. Examination may reveal generalised or localised peritonism, rebound and percussion tenderness, guarding and rigidity, and classical signs such as Rovsing’s sign and psoas sign.
Diagnosis of acute appendicitis is typically based on raised inflammatory markers and compatible history and examination findings. Imaging may be used in certain cases, such as ultrasound in females where pelvic organ pathology is suspected. Management of acute appendicitis involves appendicectomy, which can be performed via an open or laparoscopic approach. Patients with perforated appendicitis require copious abdominal lavage, while those without peritonitis who have an appendix mass should receive broad-spectrum antibiotics and consideration given to performing an interval appendicectomy. Intravenous antibiotics alone have been trialled as a treatment for appendicitis, but evidence suggests that this is associated with a longer hospital stay and up to 20% of patients go on to have an appendicectomy within 12 months.
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This question is part of the following fields:
- Gastrointestinal System
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Question 14
Correct
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A 25-year-old female presents to her GP with a 3-month history of bloating. She has tried excluding nightshades from her diet which provided some relief but her symptoms persist. Upon further questioning, she reports a lifelong feeling of incomplete bowel emptying after defecation. This symptom was previously investigated with endoscopy and biopsies, but no definitive diagnosis was made.
Additionally, she reports the presence of mucus in her stool and intermittent abdominal pain. She has no significant medical history or regular medications, but does have a peanut allergy. Her mother has coeliac disease and her father has type 2 diabetes which is managed with insulin.
What is the most likely diagnosis for this patient?Your Answer: Irritable bowel syndrome
Explanation:Diagnosis and Management of Irritable Bowel Syndrome
Irritable bowel syndrome (IBS) is a common gastrointestinal disorder that affects many people. To diagnose IBS, a patient must have experienced abdominal pain, bloating, or a change in bowel habit for at least six months. A positive diagnosis of IBS is made if the patient has abdominal pain relieved by defecation or associated with altered bowel frequency stool form, in addition to two of the following four symptoms: altered stool passage, abdominal bloating, symptoms made worse by eating, and passage of mucus. Other features such as lethargy, nausea, backache, and bladder symptoms may also support the diagnosis.
It is important to enquire about red flag features such as rectal bleeding, unexplained/unintentional weight loss, family history of bowel or ovarian cancer, and onset after 60 years of age. Primary care investigations such as a full blood count, ESR/CRP, and coeliac disease screen (tissue transglutaminase antibodies) are suggested. The National Institute for Health and Care Excellence (NICE) published clinical guidelines on the diagnosis and management of IBS in 2008 to help healthcare professionals provide the best care for patients with this condition.
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This question is part of the following fields:
- Gastrointestinal System
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Question 15
Correct
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A 32-year-old male has been diagnosed with a carcinoid tumor in his appendix. Which of the substances listed below would be useful for monitoring during his follow-up?
Your Answer: Chromogranin A
Explanation:Differentiating between blood and urine tests for carcinoid syndrome is crucial. Chromogranin A, neuron-specific enolase (NSE), substance P, and gastrin are typically measured in blood tests, while urine tests typically measure 5 HIAA, a serotonin metabolite. Occasionally, blood tests for serotonin (5 hydroxytryptamine) may also be conducted.
Carcinoid tumours are a type of cancer that can cause a condition called carcinoid syndrome. This syndrome typically occurs when the cancer has spread to the liver and releases serotonin into the bloodstream. In some cases, it can also occur with lung carcinoid tumours, as the mediators are not cleared by the liver. The earliest symptom of carcinoid syndrome is often flushing, but it can also cause diarrhoea, bronchospasm, hypotension, and right heart valvular stenosis (or left heart involvement in bronchial carcinoid). Additionally, other molecules such as ACTH and GHRH may be secreted, leading to conditions like Cushing’s syndrome. Pellagra, a rare condition caused by a deficiency in niacin, can also develop as the tumour diverts dietary tryptophan to serotonin.
To investigate carcinoid syndrome, doctors may perform a urinary 5-HIAA test or a plasma chromogranin A test. Treatment for the condition typically involves somatostatin analogues like octreotide, which can help manage symptoms like diarrhoea. Cyproheptadine may also be used to alleviate diarrhoea. Overall, early detection and treatment of carcinoid tumours can help prevent the development of carcinoid syndrome and improve outcomes for patients.
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This question is part of the following fields:
- Gastrointestinal System
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Question 16
Correct
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A patient with a history of diverticular disease presents to the surgical assessment unit with abdominal pain and a fever. Her white blood cell count is elevated, but she is otherwise stable. The diagnosis is diverticulitis. What is the best course of action for managing this condition?
Your Answer: Antibiotics, a liquid diet and analgesia
Explanation:The initial management approach for mild diverticulitis typically involves a combination of oral antibiotics, a liquid diet, and analgesia.
Understanding Diverticulitis
Diverticulitis is a condition where an out-pouching of the intestinal mucosa becomes infected. This out-pouching is called a diverticulum and the presence of these pouches is known as diverticulosis. Diverticula are common and are thought to be caused by increased pressure in the colon. They usually occur in the sigmoid colon and are more prevalent in Westerners over the age of 60. While only a quarter of people with diverticulosis experience symptoms, 75% of those who do will have an episode of diverticulitis.
Risk factors for diverticulitis include age, lack of dietary fiber, obesity (especially in younger patients), and a sedentary lifestyle. Patients with diverticular disease may experience intermittent abdominal pain, bloating, and changes in bowel habits. Those with acute diverticulitis may experience severe abdominal pain, nausea and vomiting, changes in bowel habits, and urinary symptoms. Complications may include colovesical or colovaginal fistulas.
Signs of diverticulitis include low-grade fever, tachycardia, tender lower left quadrant of the abdomen, and possibly a palpable mass. Imaging tests such as an erect chest X-ray, abdominal X-ray, and CT scan may be used to diagnose diverticulitis. Treatment may involve oral antibiotics, a liquid diet, and analgesia for mild cases. More severe cases may require hospitalization for intravenous antibiotics. Colonoscopy should be avoided initially due to the risk of perforation.
In summary, diverticulitis is a common condition that can cause significant discomfort and complications. Understanding the risk factors, symptoms, and signs of diverticulitis can help with early diagnosis and treatment.
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This question is part of the following fields:
- Gastrointestinal System
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Question 17
Correct
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A 30-year-old patient comes to see his doctor complaining of feeling fatigued, sluggish and having difficulty concentrating at work lately. He appears pale and his hands feel cool to the touch. He reports being a non-smoker, drinking very little and adopting a vegan diet last year. What could be the reason for this patient's development of anaemia?
Your Answer: Fe3+ is insoluble and must be converted into Fe2+ before it is absorbed
Explanation:Iron is absorbed from food in two forms: haem iron (found in meat) and non-haem iron (found in green vegetables). Haem iron is easier to absorb than non-haem iron. Non-haem iron is mostly in the form of insoluble ferric (Fe3+) iron, which needs to be converted to soluble ferrous (Fe2+) iron before it can be absorbed by the body. However, the amount of iron absorbed this way is often not enough to meet the body’s needs. Vegetarians and vegans are at higher risk of iron deficiency anaemia (IDA) because they consume less haem iron.
The patient’s symptoms suggest IDA caused by a change in diet, rather than anaemia of chronic disease. Ferritin is a marker of iron stores and is reduced in IDA. Hepcidin is a hormone that regulates iron storage in the body. Low serum hepcidin levels are seen in IDA, but this is not a reliable marker of the condition. Transferrin is a protein that binds to iron in the blood. In IDA, transferrin levels are high and ferritin levels are low. Transferrin saturation is low in IDA and anaemia of chronic disease, but high in haemochromatosis. Total iron-binding capacity (TIBC) is normal or high in IDA, but low in anaemia of chronic disease due to increased iron storage in cells and limited release into the blood.
Understanding Ferritin Levels in the Body
Ferritin is a protein found inside cells that binds to iron and stores it for later use. When ferritin levels are increased, it is usually defined as being above 300 µg/L in men and postmenopausal women, and above 200 µg/L in premenopausal women. However, it is important to note that ferritin is an acute phase protein, meaning that it can be synthesized in larger quantities during times of inflammation. This can lead to falsely elevated results, which must be interpreted in the context of the patient’s clinical picture and other blood test results.
There are two main categories of causes for increased ferritin levels: those without iron overload (which account for around 90% of patients) and those with iron overload (which account for around 10% of patients). Causes of increased ferritin levels without iron overload include inflammation, alcohol excess, liver disease, chronic kidney disease, and malignancy. Causes of increased ferritin levels with iron overload include primary iron overload (hereditary hemochromatosis) and secondary iron overload (which can occur after repeated transfusions).
On the other hand, reduced ferritin levels can be an indication of iron deficiency anemia. Since iron and ferritin are bound together, a decrease in ferritin levels can suggest a decrease in iron levels as well. Measuring serum ferritin levels can be helpful in determining whether a low hemoglobin level and microcytosis are truly caused by an iron deficiency state. It is important to note that the best test for determining iron overload is transferrin saturation, with normal values being less than 45% in females and less than 50% in males.
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This question is part of the following fields:
- Gastrointestinal System
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Question 18
Correct
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A 45-year-old man presents to the surgical team with abdominal pain, bloating, and vomiting. Based on an abdominal x-ray, there is suspicion of a malignancy causing intestinal obstruction. Which of the following antiemetics should be avoided for managing the patient's vomiting?
Your Answer: Metoclopramide
Explanation:It is not recommended to use metoclopramide as an antiemetic in cases of bowel obstruction. This is because metoclopramide works by blocking dopamine receptors and stimulating peripheral 5HT3 receptors, which promote gastric emptying. However, in cases of intestinal obstruction, gastric emptying is not possible and this effect can be harmful. The choice of antiemetic should be based on the patient’s individual needs and the underlying cause of their nausea.
Understanding the Mechanism and Uses of Metoclopramide
Metoclopramide is a medication primarily used to manage nausea, but it also has other uses such as treating gastro-oesophageal reflux disease and gastroparesis secondary to diabetic neuropathy. It is often combined with analgesics for the treatment of migraines. However, it is important to note that metoclopramide has adverse effects such as extrapyramidal effects, acute dystonia, diarrhoea, hyperprolactinaemia, tardive dyskinesia, and parkinsonism. It should also be avoided in bowel obstruction but may be helpful in paralytic ileus.
The mechanism of action of metoclopramide is quite complicated. It is primarily a D2 receptor antagonist, but it also has mixed 5-HT3 receptor antagonist/5-HT4 receptor agonist activity. Its antiemetic action is due to its antagonist activity at D2 receptors in the chemoreceptor trigger zone, and at higher doses, the 5-HT3 receptor antagonist also has an effect. The gastroprokinetic activity is mediated by D2 receptor antagonist activity and 5-HT4 receptor agonist activity.
In summary, metoclopramide is a medication with multiple uses, but it also has adverse effects that should be considered. Its mechanism of action is complex, involving both D2 receptor antagonist and 5-HT3 receptor antagonist/5-HT4 receptor agonist activity. Understanding the uses and mechanism of action of metoclopramide is important for its safe and effective use.
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This question is part of the following fields:
- Gastrointestinal System
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Question 19
Correct
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A 16-year-old girl complains of pain in her right iliac fossa and is diagnosed with acute appendicitis. You bring her to the operating room for a laparoscopic appendectomy. While performing the procedure, you are distracted by the scrub nurse and accidentally tear the appendicular artery, causing significant bleeding. Which vessel is likely to be the primary source of the hemorrhage?
Your Answer: Ileo-colic artery
Explanation:The ileocolic artery gives rise to the appendicular artery.
Appendix Anatomy and Location
The appendix is a small, finger-like projection located at the base of the caecum. It can be up to 10cm long and is mainly composed of lymphoid tissue, which can sometimes lead to confusion with mesenteric adenitis. The caecal taenia coli converge at the base of the appendix, forming a longitudinal muscle cover over it. This convergence can aid in identifying the appendix during surgery, especially if it is retrocaecal and difficult to locate. The arterial supply to the appendix comes from the appendicular artery, which is a branch of the ileocolic artery. It is important to note that the appendix is intra-peritoneal.
McBurney’s Point and Appendix Positions
McBurney’s point is a landmark used to locate the appendix during physical examination. It is located one-third of the way along a line drawn from the Anterior Superior Iliac Spine to the Umbilicus. The appendix can be found in six different positions, with the retrocaecal position being the most common at 74%. Other positions include pelvic, postileal, subcaecal, paracaecal, and preileal. It is important to be aware of these positions as they can affect the presentation of symptoms and the difficulty of locating the appendix during surgery.
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This question is part of the following fields:
- Gastrointestinal System
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Question 20
Incorrect
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A 65-year-old male patient is referred to the upper GI clinic under the two-week rule. His daughter first noticed that his skin and eyes are becoming yellow. His past medical history includes neurofibromatosis type 1. He was recently diagnosed with Type 2 diabetes mellitus however the blood glucose has been very poorly controlled despite maximum therapy of metformin and gliclazide. On examination, he is jaundiced. There is mild discomfort in the epigastric region and the right upper quadrant. An urgent abdominal CT scan shows a mass arising from the head of the pancreas and dilated common bile duct. A subsequent endoscopic retrograde cholangiopancreatography (ERCP) and biopsy confirms a pancreatic somatostatinoma.
From which cells in the pancreas is this tumour originating?Your Answer: I cells
Correct Answer: D cells
Explanation:Overview of Gastrointestinal Hormones
Gastrointestinal hormones play a crucial role in the digestion and absorption of food. These hormones are secreted by various cells in the stomach and small intestine in response to different stimuli such as the presence of food, pH changes, and neural signals.
One of the major hormones involved in food digestion is gastrin, which is secreted by G cells in the antrum of the stomach. Gastrin increases acid secretion by gastric parietal cells, stimulates the secretion of pepsinogen and intrinsic factor, and increases gastric motility. Another hormone, cholecystokinin (CCK), is secreted by I cells in the upper small intestine in response to partially digested proteins and triglycerides. CCK increases the secretion of enzyme-rich fluid from the pancreas, contraction of the gallbladder, and relaxation of the sphincter of Oddi. It also decreases gastric emptying and induces satiety.
Secretin is another hormone secreted by S cells in the upper small intestine in response to acidic chyme and fatty acids. Secretin increases the secretion of bicarbonate-rich fluid from the pancreas and hepatic duct cells, decreases gastric acid secretion, and has a trophic effect on pancreatic acinar cells. Vasoactive intestinal peptide (VIP) is a neural hormone that stimulates secretion by the pancreas and intestines and inhibits acid secretion.
Finally, somatostatin is secreted by D cells in the pancreas and stomach in response to fat, bile salts, and glucose in the intestinal lumen. Somatostatin decreases acid and pepsin secretion, decreases gastrin secretion, decreases pancreatic enzyme secretion, and decreases insulin and glucagon secretion. It also inhibits the trophic effects of gastrin and stimulates gastric mucous production.
In summary, gastrointestinal hormones play a crucial role in regulating the digestive process and maintaining homeostasis in the gastrointestinal tract.
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This question is part of the following fields:
- Gastrointestinal System
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Question 21
Correct
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After an oesophagogastrectomy, the surgeons will connect the remaining oesophagus to the stomach. Which layer is not included in the composition of the oesophageal wall?
Your Answer: Serosa
Explanation:Due to the absence of a serosa layer, the oesophageal wall may not provide a strong grip for sutures.
Anatomy of the Oesophagus
The oesophagus is a muscular tube that is approximately 25 cm long and starts at the C6 vertebrae, pierces the diaphragm at T10, and ends at T11. It is lined with non-keratinized stratified squamous epithelium and has constrictions at various distances from the incisors, including the cricoid cartilage at 15cm, the arch of the aorta at 22.5cm, the left principal bronchus at 27cm, and the diaphragmatic hiatus at 40cm.
The oesophagus is surrounded by various structures, including the trachea to T4, the recurrent laryngeal nerve, the left bronchus and left atrium, and the diaphragm anteriorly. Posteriorly, it is related to the thoracic duct to the left at T5, the hemiazygos to the left at T8, the descending aorta, and the first two intercostal branches of the aorta. The arterial, venous, and lymphatic drainage of the oesophagus varies depending on the location, with the upper third being supplied by the inferior thyroid artery and drained by the deep cervical lymphatics, the mid-third being supplied by aortic branches and drained by azygos branches and mediastinal lymphatics, and the lower third being supplied by the left gastric artery and drained by posterior mediastinal and coeliac veins and gastric lymphatics.
The nerve supply of the oesophagus also varies, with the upper half being supplied by the recurrent laryngeal nerve and the lower half being supplied by the oesophageal plexus of the vagus nerve. The muscularis externa of the oesophagus is composed of both smooth and striated muscle, with the composition varying depending on the location.
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This question is part of the following fields:
- Gastrointestinal System
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Question 22
Correct
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Mr Stent is a 56-year-old man who has been scheduled for a laparoscopic right hemicolectomy. However, he has several comorbidities that were discovered during the anaesthetic clinic. These include constipation, a latex allergy, coronary artery disease, moderately raised intracranial pressure due to a benign space occupying brain tumour, and a protein C deficiency. Considering his medical history, which of the following is an absolute contraindication to laparoscopic surgery?
Your Answer: Raised intracranial pressure
Explanation:Laparoscopic surgery should not be performed in patients with significantly raised intracranial pressure. It is important to understand the indications, complications, and contraindications of both laparoscopic and open surgery. Thrombophilia can be managed with anticoagulation, constipation is not a contraindication but may increase the risk of bowel perforation, a patient with a latex allergy should have all latex equipment removed and the theatre cleaned, and a patient with coronary artery disease may be at higher risk during anaesthesia but this will be assessed before surgery in the anaesthetics clinic.
Risks and Complications of Laparoscopy
Laparoscopy is a minimally invasive surgical procedure that involves the insertion of a small camera and instruments through small incisions in the abdomen. While it is generally considered safe, there are some risks and complications associated with the procedure.
One of the general risks of laparoscopy is the use of anaesthetic, which can cause complications such as allergic reactions or breathing difficulties. Additionally, some patients may experience a vasovagal reaction, which is a sudden drop in blood pressure and heart rate in response to abdominal distension.
Another potential complication of laparoscopy is extra-peritoneal gas insufflation, which can cause surgical emphysema. This occurs when gas used to inflate the abdomen during the procedure leaks into the surrounding tissues, causing swelling and discomfort.
Injuries to the gastro-intestinal tract and blood vessels are also possible complications of laparoscopy. These can include damage to the common iliacs or deep inferior epigastric artery, which can cause bleeding and other serious complications.
Overall, while laparoscopy is generally considered safe, it is important for patients to be aware of the potential risks and complications associated with the procedure. Patients should discuss these risks with their healthcare provider before undergoing laparoscopy.
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This question is part of the following fields:
- Gastrointestinal System
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Question 23
Incorrect
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A 55-year-old man is having a distal pancreatectomy due to trauma. What vessel is responsible for supplying the tail of the pancreas with arterial blood?
Your Answer: Hepatic artery
Correct Answer: Splenic artery
Explanation:The pancreaticoduodenal artery supplies the pancreatic head, while branches of the splenic artery supply the pancreatic tail. There is an arterial watershed between the two regions.
Anatomy of the Pancreas
The pancreas is located behind the stomach and is a retroperitoneal organ. It can be accessed surgically by dividing the peritoneal reflection that connects the greater omentum to the transverse colon. The pancreatic head is situated in the curvature of the duodenum, while its tail is close to the hilum of the spleen. The pancreas has various relations with other organs, such as the inferior vena cava, common bile duct, renal veins, superior mesenteric vein and artery, crus of diaphragm, psoas muscle, adrenal gland, kidney, aorta, pylorus, gastroduodenal artery, and splenic hilum.
The arterial supply of the pancreas is through the pancreaticoduodenal artery for the head and the splenic artery for the rest of the organ. The venous drainage for the head is through the superior mesenteric vein, while the body and tail are drained by the splenic vein. The ampulla of Vater is an important landmark that marks the transition from foregut to midgut and is located halfway along the second part of the duodenum. Overall, understanding the anatomy of the pancreas is crucial for surgical procedures and diagnosing pancreatic diseases.
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This question is part of the following fields:
- Gastrointestinal System
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Question 24
Correct
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At which of the subsequent spinal levels does the esophagus pass through the diaphragm and enter the abdominal cavity?
Your Answer: T10
Explanation:The point at which the oesophagus enters the abdomen is located at T10.
Anatomy of the Oesophagus
The oesophagus is a muscular tube that is approximately 25 cm long and starts at the C6 vertebrae, pierces the diaphragm at T10, and ends at T11. It is lined with non-keratinized stratified squamous epithelium and has constrictions at various distances from the incisors, including the cricoid cartilage at 15cm, the arch of the aorta at 22.5cm, the left principal bronchus at 27cm, and the diaphragmatic hiatus at 40cm.
The oesophagus is surrounded by various structures, including the trachea to T4, the recurrent laryngeal nerve, the left bronchus and left atrium, and the diaphragm anteriorly. Posteriorly, it is related to the thoracic duct to the left at T5, the hemiazygos to the left at T8, the descending aorta, and the first two intercostal branches of the aorta. The arterial, venous, and lymphatic drainage of the oesophagus varies depending on the location, with the upper third being supplied by the inferior thyroid artery and drained by the deep cervical lymphatics, the mid-third being supplied by aortic branches and drained by azygos branches and mediastinal lymphatics, and the lower third being supplied by the left gastric artery and drained by posterior mediastinal and coeliac veins and gastric lymphatics.
The nerve supply of the oesophagus also varies, with the upper half being supplied by the recurrent laryngeal nerve and the lower half being supplied by the oesophageal plexus of the vagus nerve. The muscularis externa of the oesophagus is composed of both smooth and striated muscle, with the composition varying depending on the location.
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This question is part of the following fields:
- Gastrointestinal System
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Question 25
Correct
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A 50-year-old male presents to his primary care physician with complaints of edema around his eyes and ankles. Upon further inquiry, he reports having foamy urine and is diagnosed with hypertension. The physician suggests that a biopsy of the affected organ would be the most informative diagnostic tool.
Considering the organ most likely involved in his symptoms, what would be the optimal approach for obtaining a biopsy?Your Answer: Posteriorly, inferior to the 12 rib and adjacent to the spine
Explanation:The safest way to access the kidneys is from the patient’s back, as they are retroperitoneal structures. Attempting to access them from the front or side would involve passing through the peritoneum, which increases the risk of infection. The kidneys are located near the spine and can be accessed below the 12th rib.
The retroperitoneal structures are those that are located behind the peritoneum, which is the membrane that lines the abdominal cavity. These structures include the duodenum (2nd, 3rd, and 4th parts), ascending and descending colon, kidneys, ureters, aorta, and inferior vena cava. They are situated in the back of the abdominal cavity, close to the spine. In contrast, intraperitoneal structures are those that are located within the peritoneal cavity, such as the stomach, duodenum (1st part), jejunum, ileum, transverse colon, and sigmoid colon. It is important to note that the retroperitoneal structures are not well demonstrated in the diagram as the posterior aspect has been removed, but they are still significant in terms of their location and function.
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This question is part of the following fields:
- Gastrointestinal System
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Question 26
Correct
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A 10-year-old girl is undergoing investigation for coeliac disease and has recently undergone biopsies of both the small and large intestinal linings.
What can be found in the lining of the small intestine but not in that of the large intestine during a normal biopsy?Your Answer: Villi
Explanation:The basic structure of the linings in the small and large intestines is similar, consisting of mucosa, submucosa, muscularis externa, and serosa. Both intestines have muscularis mucosae within the mucosa, myenteric nerve plexus innervating the muscularis externa, columnar epithelial cells lining the mucosa, and goblet cells that secrete mucins. However, each intestine has specialized functions. The small intestine is responsible for digesting and absorbing nutrients, which is facilitated by the presence of villi and microvilli on its epithelium, providing a large surface area. These structures are not present in the large intestine.
Layers of the Gastrointestinal Tract and Their Functions
The gastrointestinal (GI) tract is composed of four layers, each with its own unique function. The innermost layer is the mucosa, which can be further divided into three sublayers: the epithelium, lamina propria, and muscularis mucosae. The epithelium is responsible for absorbing nutrients and secreting mucus, while the lamina propria contains blood vessels and immune cells. The muscularis mucosae helps to move food along the GI tract.
The submucosa is the layer that lies beneath the mucosa and contains Meissner’s plexus, which is responsible for regulating secretion and blood flow. The muscularis externa is the layer that lies beneath the submucosa and contains Auerbach’s plexus, which controls the motility of GI smooth muscle. Finally, the outermost layer of the GI tract is either the serosa or adventitia, depending on whether the organ is intraperitoneal or retroperitoneal. The serosa is responsible for secreting fluid to lubricate the organs, while the adventitia provides support and protection. Understanding the functions of each layer is important for understanding the overall function of the GI tract.
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This question is part of the following fields:
- Gastrointestinal System
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Question 27
Correct
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An 80-year-old male visits his GP with a complaint of blood in his stool and increased frequency of bowel movements. He has also experienced mild weight loss due to a change in appetite. Upon referral to secondary care, a mass is discovered in his ascending colon. If the mass were to perforate the bowel wall, where would bowel gas most likely accumulate?
Your Answer: Retroperitoneal space
Explanation:The patient’s symptoms suggest that he may have bowel cancer in his ascending colon. As the ascending colon is located behind the peritoneum, a rupture of the colon could lead to the accumulation of gas in the retroperitoneal space.
Pneumoperitoneum, which is the presence of gas in the peritoneum, is typically caused by a perforated peptic ulcer. On the other hand, subcutaneous emphysema is the trapping of air under the skin layer and is usually associated with chest wall trauma or pneumothorax.
Air in the intra-mural space refers to the presence of air within the bowel wall and is not likely to occur in cases of perforation. This condition is typically associated with intestinal ischaemia and infarction.
The retroperitoneal structures are those that are located behind the peritoneum, which is the membrane that lines the abdominal cavity. These structures include the duodenum (2nd, 3rd, and 4th parts), ascending and descending colon, kidneys, ureters, aorta, and inferior vena cava. They are situated in the back of the abdominal cavity, close to the spine. In contrast, intraperitoneal structures are those that are located within the peritoneal cavity, such as the stomach, duodenum (1st part), jejunum, ileum, transverse colon, and sigmoid colon. It is important to note that the retroperitoneal structures are not well demonstrated in the diagram as the posterior aspect has been removed, but they are still significant in terms of their location and function.
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This question is part of the following fields:
- Gastrointestinal System
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Question 28
Correct
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A 55-year-old man comes to the emergency department complaining of sudden abdominal pain in the epigastric region. He has a history of heavy alcohol consumption, but this is his first visit to the department. Upon examination, he is sweating profusely and has a fever. His heart rate is 130 beats per minute, and his blood pressure is 90/60 mmHg. You diagnose him with acute pancreatitis and are concerned about potential complications.
What symptom is most likely to be present in this patient?Your Answer: Blue discolouration of the flank regions
Explanation:The patient is experiencing acute pancreatitis, possibly due to excessive alcohol consumption. As this is his first visit to the emergency department, it is unlikely to be a sudden attack on top of chronic pancreatitis. The presence of tachycardia and hypotension suggests that he is also experiencing blood loss. The correct answer should identify an acute condition associated with blood loss.
a. Bulky, greasy stools are a long-term complication of chronic pancreatitis, indicating that the pancreas has lost its exocrine function and is unable to properly digest food.
b. Grey Turner’s sign is a sign of blood pooling in the retroperitoneal space, which can occur due to inflammation of the retroperitoneal pancreas.
c. This is a complication of long-term diabetes or chronic pancreatitis.
d. Ascites is not typically associated with an acute first-time presentation of pancreatitis, although it can have many causes.
e. This description is typical of an abdominal obstruction, which may cause nausea and vomiting.
The retroperitoneal structures are those that are located behind the peritoneum, which is the membrane that lines the abdominal cavity. These structures include the duodenum (2nd, 3rd, and 4th parts), ascending and descending colon, kidneys, ureters, aorta, and inferior vena cava. They are situated in the back of the abdominal cavity, close to the spine. In contrast, intraperitoneal structures are those that are located within the peritoneal cavity, such as the stomach, duodenum (1st part), jejunum, ileum, transverse colon, and sigmoid colon. It is important to note that the retroperitoneal structures are not well demonstrated in the diagram as the posterior aspect has been removed, but they are still significant in terms of their location and function.
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This question is part of the following fields:
- Gastrointestinal System
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Question 29
Correct
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A 3-year-old girl is brought to the emergency department due to severe abdominal pain. She has tenderness throughout her abdomen, but it is especially painful in the right iliac fossa. Her parents are concerned because they noticed blood in her stool earlier today.
The patient is admitted and receives appropriate treatment. Further investigations reveal the presence of ectopic ileal mucosa.
What is the probable underlying condition?Your Answer: Meckel's diverticulum
Explanation:Meckel’s diverticulum is the most likely diagnosis for this child’s symptoms. It is a congenital condition that affects about 2% of the population and typically presents with symptoms around the age of 2. Some children with Meckel’s diverticulum may develop diverticulitis, which can be mistaken for appendicitis. The presence of ectopic ileal mucosa is a key factor in diagnosing Meckel’s diverticulum.
Appendicitis is an unlikely diagnosis as it would not explain the presence of ectopic ileal mucosa. Duodenal atresia is also unlikely as it typically presents in newborns and is associated with Down’s syndrome. Necrotising enterocolitis is another unlikely diagnosis as it primarily affects premature infants and would not explain the ectopic ileal mucosa.
Meckel’s diverticulum is a congenital diverticulum of the small intestine that is a remnant of the omphalomesenteric duct. It occurs in 2% of the population, is 2 feet from the ileocaecal valve, and is 2 inches long. It is usually asymptomatic but can present with abdominal pain, rectal bleeding, or intestinal obstruction. Investigation includes a Meckel’s scan or mesenteric arteriography. Management involves removal if narrow neck or symptomatic, with options between wedge excision or formal small bowel resection and anastomosis. Meckel’s diverticulum is typically lined by ileal mucosa but ectopic gastric, pancreatic, and jejunal mucosa can also occur.
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This question is part of the following fields:
- Gastrointestinal System
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Question 30
Correct
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Surgical occlusion of which of these structures will cause the most significant decrease in hepatic blood flow?
Your Answer: Portal vein
Explanation:The contents of the portal vein consist of digested products. Sinusoids distribute arterial and venous blood to the central veins of the liver lobules, which then empty into the hepatic veins and ultimately into the IVC. Unlike other hepatic veins, the caudate lobe directly drains into the IVC.
Structure and Relations of the Liver
The liver is divided into four lobes: the right lobe, left lobe, quadrate lobe, and caudate lobe. The right lobe is supplied by the right hepatic artery and contains Couinaud segments V to VIII, while the left lobe is supplied by the left hepatic artery and contains Couinaud segments II to IV. The quadrate lobe is part of the right lobe anatomically but functionally is part of the left, and the caudate lobe is supplied by both right and left hepatic arteries and lies behind the plane of the porta hepatis. The liver lobules are separated by portal canals that contain the portal triad: the hepatic artery, portal vein, and tributary of bile duct.
The liver has various relations with other organs in the body. Anteriorly, it is related to the diaphragm, esophagus, xiphoid process, stomach, duodenum, hepatic flexure of colon, right kidney, gallbladder, and inferior vena cava. The porta hepatis is located on the postero-inferior surface of the liver and transmits the common hepatic duct, hepatic artery, portal vein, sympathetic and parasympathetic nerve fibers, and lymphatic drainage of the liver and nodes.
The liver is supported by ligaments, including the falciform ligament, which is a two-layer fold of peritoneum from the umbilicus to the anterior liver surface and contains the ligamentum teres (remnant of the umbilical vein). The ligamentum venosum is a remnant of the ductus venosus. The liver is supplied by the hepatic artery and drained by the hepatic veins and portal vein. Its nervous supply comes from the sympathetic and parasympathetic trunks of the coeliac plexus.
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This question is part of the following fields:
- Gastrointestinal System
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Question 31
Correct
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During a left hemicolectomy the sigmoid colon is mobilised. As the bowel is retracted medially a vessel is injured, anterior to the colon. Which one of the following is the most likely vessel?
Your Answer: Gonadal vessels
Explanation:During a right hemicolectomy, the gonadal vessels and ureter are crucial structures located at the posterior aspect that may be vulnerable to injury.
The Caecum: Location, Relations, and Functions
The caecum is a part of the colon located in the proximal right colon below the ileocaecal valve. It is an intraperitoneal structure that has posterior relations with the psoas, iliacus, femoral nerve, genitofemoral nerve, and gonadal vessels. Its anterior relations include the greater omentum. The caecum is supplied by the ileocolic artery and its lymphatic drainage is through the mesenteric nodes that accompany the venous drainage.
The caecum is known for its distensibility, making it the most distensible part of the colon. However, in cases of complete large bowel obstruction with a competent ileocaecal valve, the caecum is the most likely site of eventual perforation. Despite this potential complication, the caecum plays an important role in the digestive system. It is responsible for the absorption of fluids and electrolytes, as well as the fermentation of indigestible carbohydrates. Additionally, the caecum is a site for the growth and proliferation of beneficial bacteria that aid in digestion and immune function.
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This question is part of the following fields:
- Gastrointestinal System
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Question 32
Incorrect
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A man in his early 50s arrives at the Emergency Department complaining of abdominal pain and haematemesis. Upon diagnosis, he is found to have a peptic ulcer. During his treatment, he reveals that he has been taking ibuprofen for several years. His physician informs him that this may have caused the bleeding and recommends taking omeprazole, a gastroprotective medication, in addition to his ibuprofen to lower his chances of recurrence. What is the mechanism of action of omeprazole?
Your Answer: Gastric chief cell H+/K+-ATPase inhibition
Correct Answer: Gastric parietal cell H+/K+-ATPase inhibition
Explanation:The irreversible blockade of H+/K+ ATPase is caused by PPIs.
Parietal cells contain H+/K+-ATPase, which is inhibited by omeprazole, a proton pump inhibitor. Therefore, any answer indicating chief cells or H+/K+-ATPase stimulation is incorrect and potentially harmful.
Ranitidine is an example of a different class of gastroprotective drugs that inhibits H2 receptors.
Understanding Proton Pump Inhibitors
Proton pump inhibitors (PPIs) are medications that work by blocking the H+/K+ ATPase in the stomach’s parietal cells. This action is irreversible and helps to reduce the amount of acid produced in the stomach. Examples of PPIs include omeprazole and lansoprazole.
Despite their effectiveness in treating conditions such as gastroesophageal reflux disease (GERD) and peptic ulcers, PPIs can have adverse effects. These include hyponatremia and hypomagnesemia, which are low levels of sodium and magnesium in the blood, respectively. Prolonged use of PPIs can also increase the risk of osteoporosis, leading to an increased risk of fractures. Additionally, there is a potential for microscopic colitis and an increased risk of C. difficile infections.
It is important to weigh the benefits and risks of PPIs with your healthcare provider and to use them only as directed. Regular monitoring of electrolyte levels and bone density may also be necessary for those on long-term PPI therapy.
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This question is part of the following fields:
- Gastrointestinal System
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Question 33
Correct
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A 78-year-old man is assessed by his GP at his assisted living facility. The nursing staff reports that he has been experiencing frequent loose stools for the past few days and appears to be holding his stomach in pain. There are no signs of dehydration.
The patient has a medical history of advanced vascular dementia and has had multiple bacterial chest infections recently. He is allergic to penicillin.
The GP requests a stool sample, conducts blood tests, and prescribes oral vancomycin for the patient.
What are the expected findings on stool microscopy?Your Answer: Gram-positive bacilli
Explanation:The causative organism in pseudomembranous colitis following recent broad-spectrum antibiotic use is Clostridium difficile, a gram-positive bacillus. This woman’s clinical presentation is consistent with C. diff infection, as she has experienced multiple episodes of loose stool with abdominal pain and has risk factors such as residing in a care home and recent antibiotic use for chest infections. While gram-negative comma-shaped bacteria like Vibrio cholerae can cause cholera, it is not found in the UK and is therefore unlikely to be the cause here. Gram-negative rods like Escherichia coli or Campylobacter jejuni can cause diarrhoeal illnesses, but are more associated with bloody diarrhoea and food poisoning, which do not match this woman’s symptoms. Gram-positive rods like Bacillus cereus can cause vomiting or diarrhoeal illness from contaminated food, but antibiotics are not beneficial and vancomycin would not be needed. Given the woman’s risk factors and symptoms, C. diff is the most likely cause.
Clostridium difficile is a type of bacteria that is commonly found in hospitals. It produces a toxin that can damage the intestines and cause a condition called pseudomembranous colitis. This bacteria usually develops when the normal gut flora is disrupted by broad-spectrum antibiotics, with second and third generation cephalosporins being the leading cause. Other risk factors include the use of proton pump inhibitors. Symptoms of C. difficile infection include diarrhea, abdominal pain, and a raised white blood cell count. The severity of the infection can be determined using the Public Health England severity scale.
To diagnose C. difficile infection, a stool sample is tested for the presence of the C. difficile toxin. Treatment involves reviewing current antibiotic therapy and stopping antibiotics if possible. For a first episode of infection, oral vancomycin is the first-line therapy for 10 days, followed by oral fidaxomicin as second-line therapy and oral vancomycin with or without IV metronidazole as third-line therapy. Recurrent infections may require different treatment options, such as oral fidaxomicin within 12 weeks of symptom resolution or oral vancomycin or fidaxomicin after 12 weeks of symptom resolution. In life-threatening cases, oral vancomycin and IV metronidazole may be used, and surgery may be considered with specialist advice. Other therapies, such as bezlotoxumab and fecal microbiota transplant, may also be considered for preventing recurrences in certain cases.
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This question is part of the following fields:
- Gastrointestinal System
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Question 34
Correct
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Which of the following is more frequently observed in individuals with Crohn's disease compared to those with ulcerative colitis?
Your Answer: Fat wrapping of the terminal ileum
Explanation:Smoking has been found to exacerbate Crohn’s disease, and it also increases the risk of disease recurrence after resection. Patients with ileal disease, which is the most common site of the disease, often exhibit fat wrapping of the terminal ileum. The mesenteric fat in patients with inflammatory bowel disease (IBD) is typically dense, hard, and prone to significant bleeding during surgery. During endoscopy, the mucosa in Crohn’s disease patients is described as resembling cobblestones, while ulcerative colitis patients often exhibit mucosal islands (pseudopolyps).
Understanding Crohn’s Disease
Crohn’s disease is a type of inflammatory bowel disease that can affect any part of the digestive tract, from the mouth to the anus. The exact cause of Crohn’s disease is unknown, but there is a strong genetic component. Inflammation occurs in all layers of the affected area, which can lead to complications such as strictures, fistulas, and adhesions.
Symptoms of Crohn’s disease typically appear in late adolescence or early adulthood and can include non-specific symptoms such as weight loss and lethargy, as well as more specific symptoms like diarrhea, abdominal pain, and perianal disease. Extra-intestinal features, such as arthritis, erythema nodosum, and osteoporosis, are also common in patients with Crohn’s disease.
To diagnose Crohn’s disease, doctors may look for raised inflammatory markers, increased faecal calprotectin, anemia, and low levels of vitamin B12 and vitamin D. It’s important to note that Crohn’s disease shares some features with ulcerative colitis, another type of inflammatory bowel disease, but there are also important differences between the two conditions. Understanding the symptoms and diagnostic criteria for Crohn’s disease can help patients and healthcare providers manage this chronic condition more effectively.
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This question is part of the following fields:
- Gastrointestinal System
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Question 35
Correct
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A 59-year-old male arrives at the emergency department complaining of severe abdominal pain, vomiting, and swelling in the central abdomen.
During his last visit to his family doctor two weeks ago, he experienced colicky abdominal pain and was diagnosed with gallstones after further testing. He was scheduled for an elective cholecystectomy in 8 weeks.
The patient is administered pain relief and scheduled for an urgent abdominal X-ray (AXR).
What is the most probable finding on the AXR that indicates a cholecystoenteric fistula?Your Answer: Pneumobilia
Explanation:The presence of air in the gallbladder and biliary tree on an abdominal X-ray is most likely caused by a cholecystoenteric fistula. This is a serious complication of gallstones, particularly those larger than 2 cm, and can result in symptoms of small bowel obstruction such as severe abdominal pain, vomiting, and abdominal distension. While pneumoperitoneum may also be present in cases of cholecystoenteric fistula, it is not a specific finding and can be caused by other factors that weaken or tear hollow viscus organs. On the other hand, the presence of an appendicolith, a small calcified stone in the appendix, is highly indicative of appendicitis in patients with right iliac fossa pain and other associated symptoms, but is not seen in cases of cholecystoenteric fistula on an abdominal X-ray.
Gallstones are a common condition, with up to 24% of women and 12% of men affected. Local infection and cholecystitis may develop in up to 30% of cases, and 12% of patients undergoing surgery will have stones in the common bile duct. The majority of gallstones are of mixed composition, with pure cholesterol stones accounting for 20% of cases. Symptoms typically include colicky right upper quadrant pain that worsens after fatty meals. Diagnosis is usually made through abdominal ultrasound and liver function tests, with magnetic resonance cholangiography or intraoperative imaging used to confirm suspected bile duct stones. Treatment options include expectant management for asymptomatic gallstones, laparoscopic cholecystectomy for symptomatic gallstones, and surgical management for stones in the common bile duct. ERCP may be used to remove bile duct stones, but carries risks such as bleeding, duodenal perforation, cholangitis, and pancreatitis.
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This question is part of the following fields:
- Gastrointestinal System
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Question 36
Correct
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You are participating in a ward round in the elective general surgical ward and come across a patient who recently underwent a Whipple's procedure for a known adenocarcinoma. The consultant discusses the case with you and mentions that the patient, who is in their 50s, presented with painless jaundice, weight loss, and steatorrhea.
Based on these symptoms, which genetic mutation is most likely to be present?Your Answer: KRAS
Explanation:Pancreatic cancer is a type of cancer that is often diagnosed late due to its non-specific symptoms. The majority of pancreatic tumors are adenocarcinomas and are typically found in the head of the pancreas. Risk factors for pancreatic cancer include increasing age, smoking, diabetes, chronic pancreatitis, hereditary non-polyposis colorectal carcinoma, and mutations in the BRCA2 and KRAS genes.
Symptoms of pancreatic cancer can include painless jaundice, pale stools, dark urine, and pruritus. Courvoisier’s law states that a palpable gallbladder is unlikely to be due to gallstones in the presence of painless obstructive jaundice. However, patients often present with non-specific symptoms such as anorexia, weight loss, and epigastric pain. Loss of exocrine and endocrine function can also occur, leading to steatorrhea and diabetes mellitus. Atypical back pain and migratory thrombophlebitis (Trousseau sign) are also common.
Ultrasound has a sensitivity of around 60-90% for detecting pancreatic cancer, but high-resolution CT scanning is the preferred diagnostic tool. The ‘double duct’ sign, which is the simultaneous dilatation of the common bile and pancreatic ducts, may be seen on imaging.
Less than 20% of patients with pancreatic cancer are suitable for surgery at the time of diagnosis. A Whipple’s resection (pancreaticoduodenectomy) may be performed for resectable lesions in the head of the pancreas, but side-effects such as dumping syndrome and peptic ulcer disease can occur. Adjuvant chemotherapy is typically given following surgery, and ERCP with stenting may be used for palliation.
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This question is part of the following fields:
- Gastrointestinal System
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Question 37
Correct
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A case of ischaemic left colon is diagnosed in a patient. Which artery, originating from the aorta at approximately the level of L3, is the most probable cause of this condition?
Your Answer: Inferior mesenteric artery
Explanation:The left side of the colon is most likely to be affected by the IMA, which typically originates at L3.
The Inferior Mesenteric Artery: Supplying the Hindgut
The inferior mesenteric artery (IMA) is responsible for supplying the embryonic hindgut with blood. It originates just above the aortic bifurcation, at the level of L3, and passes across the front of the aorta before settling on its left side. At the point where the left common iliac artery is located, the IMA becomes the superior rectal artery.
The hindgut, which includes the distal third of the colon and the rectum above the pectinate line, is supplied by the IMA. The left colic artery is one of the branches that emerges from the IMA near its origin. Up to three sigmoid arteries may also exit the IMA to supply the sigmoid colon further down the line.
Overall, the IMA plays a crucial role in ensuring that the hindgut receives the blood supply it needs to function properly. Its branches help to ensure that the colon and rectum are well-nourished and able to carry out their important digestive functions.
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This question is part of the following fields:
- Gastrointestinal System
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Question 38
Correct
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A 55-year-old man presents to the emergency department with haematemesis which he has never experienced before. He reports a 3 week history of intermittent dull pain in the upper left quadrant and, upon further inquiry, he mentions that he believes he has been losing weight but he doesn't weigh himself often as he has always been in good shape. Other than a badly sprained ankle 10 weeks ago, for which he admits he is still taking ibuprofen, he has no medical conditions and is not taking any regular medication. He is a non-smoker and only drinks alcohol occasionally. What is the most probable cause of the patient's haematemesis?
Your Answer: Peptic ulcer
Explanation:Peptic ulcer is a frequent cause of haematemesis in patients who have been using NSAIDs extensively, as seen in this patient’s case. Peptic ulcers can manifest with various symptoms such as haematemesis, abdominal pain, nausea, weight loss, and acid reflux. Typically, the pain subsides when the patient eats or drinks.
Although weight loss can be a sign of malignancy, this patient has few risk factors (over 55 years old, smoker, high alcohol consumption, and obesity).
Any instance of repeated forceful vomiting can lead to a mallory-weiss tear, which presents as painful episodes of haematemesis.
Oesophageal varices are expected in patients with a history of alcohol abuse and usually present with signs of chronic liver disease.
Hereditary telangiectasia usually presents with a positive family history and telangiectasia around the lips, tongue, or mucus membranes. Epistaxis is a common symptom of this vascular malformation.
Helicobacter pylori: A Bacteria Associated with Gastrointestinal Problems
Helicobacter pylori is a type of Gram-negative bacteria that is commonly associated with various gastrointestinal problems, particularly peptic ulcer disease. This bacterium has two primary mechanisms that allow it to survive in the acidic environment of the stomach. Firstly, it uses its flagella to move away from low pH areas and burrow into the mucous lining to reach the epithelial cells underneath. Secondly, it secretes urease, which converts urea to NH3, leading to an alkalinization of the acidic environment and increased bacterial survival.
The pathogenesis mechanism of Helicobacter pylori involves the release of bacterial cytotoxins, such as the CagA toxin, which can disrupt the gastric mucosa. This bacterium is associated with several gastrointestinal problems, including peptic ulcer disease, gastric cancer, B cell lymphoma of MALT tissue, and atrophic gastritis. However, its role in gastro-oesophageal reflux disease (GORD) is unclear, and there is currently no role for the eradication of Helicobacter pylori in GORD.
The management of Helicobacter pylori infection involves a 7-day course of treatment with a proton pump inhibitor, amoxicillin, and either clarithromycin or metronidazole. For patients who are allergic to penicillin, a proton pump inhibitor, metronidazole, and clarithromycin are used instead.
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This question is part of the following fields:
- Gastrointestinal System
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Question 39
Correct
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A 67-year-old woman visits her GP after discovering a lump in her groin subsequent to relocating. The patient reports that she can push the lump back in, but it returns when she coughs. During the examination, the GP identifies the lump located superior and medial to the pubic tubercle. The GP reduces the lump, applies pressure to the midpoint of the inguinal ligament, and instructs the patient to cough. The lump reappears, leading the GP to tentatively diagnose the patient with a direct inguinal hernia. Through which anatomical structures will the hernia pass?
Your Answer: Transversalis fascia and superficial inguinal ring
Explanation:The correct structures for a direct inguinal hernia to pass through are the transversalis fascia (which forms the posterior wall of the inguinal canal) and the superficial ring. If the hernia were to pass through other structures, such as the deep inguinal ring, it would reappear upon increased intra-abdominal pressure. In contrast, an indirect inguinal hernia enters the canal through the deep inguinal ring and exits at the superficial ring, so it would not reappear if the deep inguinal ring were blocked.
The inguinal canal is located above the inguinal ligament and measures 4 cm in length. Its superficial ring is situated in front of the pubic tubercle, while the deep ring is found about 1.5-2 cm above the halfway point between the anterior superior iliac spine and the pubic tubercle. The canal is bounded by the external oblique aponeurosis, inguinal ligament, lacunar ligament, internal oblique, transversus abdominis, external ring, and conjoint tendon. In males, the canal contains the spermatic cord and ilioinguinal nerve, while in females, it houses the round ligament of the uterus and ilioinguinal nerve.
The boundaries of Hesselbach’s triangle, which are frequently tested, are located in the inguinal region. Additionally, the inguinal canal is closely related to the vessels of the lower limb, which should be taken into account when repairing hernial defects in this area.
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This question is part of the following fields:
- Gastrointestinal System
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Question 40
Correct
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What is the urinary diagnostic marker for carcinoid syndrome in elderly patients?
Your Answer: 5-Hydroxyindoleacetic acid
Explanation:The measurement of 5-HIAA in urine is a crucial aspect of clinical monitoring.
Carcinoid tumours are a type of cancer that can cause a condition called carcinoid syndrome. This syndrome typically occurs when the cancer has spread to the liver and releases serotonin into the bloodstream. In some cases, it can also occur with lung carcinoid tumours, as the mediators are not cleared by the liver. The earliest symptom of carcinoid syndrome is often flushing, but it can also cause diarrhoea, bronchospasm, hypotension, and right heart valvular stenosis (or left heart involvement in bronchial carcinoid). Additionally, other molecules such as ACTH and GHRH may be secreted, leading to conditions like Cushing’s syndrome. Pellagra, a rare condition caused by a deficiency in niacin, can also develop as the tumour diverts dietary tryptophan to serotonin.
To investigate carcinoid syndrome, doctors may perform a urinary 5-HIAA test or a plasma chromogranin A test. Treatment for the condition typically involves somatostatin analogues like octreotide, which can help manage symptoms like diarrhoea. Cyproheptadine may also be used to alleviate diarrhoea. Overall, early detection and treatment of carcinoid tumours can help prevent the development of carcinoid syndrome and improve outcomes for patients.
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This question is part of the following fields:
- Gastrointestinal System
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Question 41
Correct
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Which one of the following is not produced by the parietal cells?
Your Answer: Mucus
Explanation:The chief cells responsible for producing Pepsi cola are not to be confused with the chief cells found in the stomach. In the stomach, chief cells secrete pepsinogen, while parietal cells secrete HCl, Ca, Na, Mg, and intrinsic factor. Additionally, surface mucosal cells secrete mucus and bicarbonate.
Understanding Gastric Secretions for Surgical Procedures
A basic understanding of gastric secretions is crucial for surgeons, especially when dealing with patients who have undergone acid-lowering procedures or are prescribed anti-secretory drugs. Gastric acid, produced by the parietal cells in the stomach, has a pH of around 2 and is maintained by the H+/K+ ATPase pump. Sodium and chloride ions are actively secreted from the parietal cell into the canaliculus, creating a negative potential across the membrane. Carbonic anhydrase forms carbonic acid, which dissociates, and the hydrogen ions formed by dissociation leave the cell via the H+/K+ antiporter pump. This leaves hydrogen and chloride ions in the canaliculus, which mix and are secreted into the lumen of the oxyntic gland.
There are three phases of gastric secretion: the cephalic phase, gastric phase, and intestinal phase. The cephalic phase is stimulated by the smell or taste of food and causes 30% of acid production. The gastric phase, which is caused by stomach distension, low H+, or peptides, causes 60% of acid production. The intestinal phase, which is caused by high acidity, distension, or hypertonic solutions in the duodenum, inhibits gastric acid secretion via enterogastrones and neural reflexes.
The regulation of gastric acid production involves various factors that increase or decrease production. Factors that increase production include vagal nerve stimulation, gastrin release, and histamine release. Factors that decrease production include somatostatin, cholecystokinin, and secretin. Understanding these factors and their associated pharmacology is essential for surgeons.
In summary, a working knowledge of gastric secretions is crucial for surgical procedures, especially when dealing with patients who have undergone acid-lowering procedures or are prescribed anti-secretory drugs. Understanding the phases of gastric secretion and the regulation of gastric acid production is essential for successful surgical outcomes.
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This question is part of the following fields:
- Gastrointestinal System
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Question 42
Correct
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A 54-year-old male visits his GP complaining of sudden and severe abdominal pain that extends to his back. He has a history of heavy alcohol consumption, osteoarthritis, and asthma, and is a smoker. He is currently taking a salbutamol and corticosteroid inhaler. During the examination, his BMI is found to be 35kg/m².
What is the most probable reason for his symptoms?Your Answer: Heavy alcohol use
Explanation:Pancreatitis is most commonly caused by heavy alcohol use and gallstones, while osteoarthritis and smoking are not direct contributors. However, the use of a steroid inhaler and a high BMI may also play a role in the development of pancreatitis by potentially leading to hypertriglyceridemia.
Acute pancreatitis is a condition that is primarily caused by gallstones and alcohol consumption in the UK. However, there are other factors that can contribute to the development of this condition. A popular mnemonic used to remember these factors is GET SMASHED, which stands for gallstones, ethanol, trauma, steroids, mumps, autoimmune diseases, scorpion venom, hypertriglyceridaemia, hyperchylomicronaemia, hypercalcaemia, hypothermia, ERCP, and certain drugs. It is important to note that pancreatitis is seven times more common in patients taking mesalazine than sulfasalazine. CT scans can show diffuse parenchymal enlargement with oedema and indistinct margins in patients with acute pancreatitis.
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This question is part of the following fields:
- Gastrointestinal System
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Question 43
Correct
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A 49-year-old woman comes to the Emergency Department complaining of colicky abdominal pain. She states that she has been having on-and-off pain in the upper right quadrant for the past few months, especially after consuming fatty foods.
Which cells are accountable for generating the hormone linked to this presentation?Your Answer: I cells
Explanation:The correct answer is I cells, which are located in the upper small intestine. This patient’s symptoms are consistent with biliary colic, which occurs when the gallbladder contracts against an obstruction, typically a gallstone. Fatty foods stimulate the production of cholecystokinin (CCK) from the I cells in the duodenum, which promotes gallbladder contractility and the release of bile into the small intestine to aid in lipid emulsification.
B cells are not involved in promoting gallbladder contractility and are instead part of the adaptive immune response. D cells release somatostatin, which decreases insulin production, and are found in the stomach, small intestine, and pancreas. G cells are located in the stomach and secrete gastrin to promote acid secretion by the parietal cells of the stomach.
Overview of Gastrointestinal Hormones
Gastrointestinal hormones play a crucial role in the digestion and absorption of food. These hormones are secreted by various cells in the stomach and small intestine in response to different stimuli such as the presence of food, pH changes, and neural signals.
One of the major hormones involved in food digestion is gastrin, which is secreted by G cells in the antrum of the stomach. Gastrin increases acid secretion by gastric parietal cells, stimulates the secretion of pepsinogen and intrinsic factor, and increases gastric motility. Another hormone, cholecystokinin (CCK), is secreted by I cells in the upper small intestine in response to partially digested proteins and triglycerides. CCK increases the secretion of enzyme-rich fluid from the pancreas, contraction of the gallbladder, and relaxation of the sphincter of Oddi. It also decreases gastric emptying and induces satiety.
Secretin is another hormone secreted by S cells in the upper small intestine in response to acidic chyme and fatty acids. Secretin increases the secretion of bicarbonate-rich fluid from the pancreas and hepatic duct cells, decreases gastric acid secretion, and has a trophic effect on pancreatic acinar cells. Vasoactive intestinal peptide (VIP) is a neural hormone that stimulates secretion by the pancreas and intestines and inhibits acid secretion.
Finally, somatostatin is secreted by D cells in the pancreas and stomach in response to fat, bile salts, and glucose in the intestinal lumen. Somatostatin decreases acid and pepsin secretion, decreases gastrin secretion, decreases pancreatic enzyme secretion, and decreases insulin and glucagon secretion. It also inhibits the trophic effects of gastrin and stimulates gastric mucous production.
In summary, gastrointestinal hormones play a crucial role in regulating the digestive process and maintaining homeostasis in the gastrointestinal tract.
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This question is part of the following fields:
- Gastrointestinal System
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Question 44
Correct
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An 80-year-old man visits his GP complaining of indigestion that has persisted for the last three months. He has a medical history of hypertension and is a heavy smoker with a 50-pack-year history. He also consumes three glasses of wine on weeknights. Upon referral to a gastroenterologist, a lower oesophageal and stomach biopsy is performed, revealing metaplastic columnar epithelium. What is the primary factor that has contributed to the development of this histological finding?
Your Answer: Gastro-oesophageal reflux disease (GORD)
Explanation:Barrett’s oesophagus is diagnosed in this patient based on the presence of metaplastic columnar epithelium in the oesophageal epithelium. The most significant risk factor for the development of Barrett’s oesophagus is gastro-oesophageal reflux disease (GORD). While age is also a risk factor, it is not as strong as GORD. Alcohol consumption is not associated with Barrett’s oesophagus, but it is a risk factor for squamous cell oesophageal carcinoma. Infection with Helicobacter pylori is not linked to Barrett’s oesophagus, and it may even reduce the risk of GORD and Barrett’s oesophagus. Smoking is associated with both GORD and Barrett’s oesophagus, but the strength of this association is not as significant as that of GORD.
Barrett’s oesophagus is a condition where the lower oesophageal mucosa is replaced by columnar epithelium, which increases the risk of oesophageal adenocarcinoma by 50-100 fold. It is usually identified during an endoscopy for upper gastrointestinal symptoms such as dyspepsia, as there are no screening programs for it. The length of the affected segment determines the chances of identifying metaplasia, with short (<3 cm) and long (>3 cm) subtypes. The prevalence of Barrett’s oesophagus is estimated to be around 1 in 20, and it is identified in up to 12% of those undergoing endoscopy for reflux.
The columnar epithelium in Barrett’s oesophagus may resemble that of the cardiac region of the stomach or that of the small intestine, with goblet cells and brush border. The single strongest risk factor for Barrett’s oesophagus is gastro-oesophageal reflux disease (GORD), followed by male gender, smoking, and central obesity. Alcohol is not an independent risk factor for Barrett’s, but it is associated with both GORD and oesophageal cancer. Patients with Barrett’s oesophagus often have coexistent GORD symptoms.
The management of Barrett’s oesophagus involves high-dose proton pump inhibitor, although the evidence base for its effectiveness in reducing the progression to dysplasia or inducing regression of the lesion is limited. Endoscopic surveillance with biopsies is recommended every 3-5 years for patients with metaplasia but not dysplasia. If dysplasia of any grade is identified, endoscopic intervention is offered, such as radiofrequency ablation, which is the preferred first-line treatment, particularly for low-grade dysplasia, or endoscopic mucosal resection.
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This question is part of the following fields:
- Gastrointestinal System
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Question 45
Correct
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A 32-year-old female undergoes an emergency caesarean section due to failed induction of labor and a macrosomic baby. After delivery, she is transferred to the postnatal ward. However, prior to discharge, she complains of abdominal pain, has a fever of 39ºC, and a tachycardia of 106 bpm. A CT scan reveals the presence of fluid accumulation in the retroperitoneal space. What is the probable cause of these CT findings?
Your Answer: Ureteral injury during caesarean section
Explanation:If the ureters are damaged during a caesarean section, it can cause fluid to accumulate in the retroperitoneal area. This can lead to pain and inflammation, which may present as fever and a rapid heartbeat. Ovarian thrombus is a rare complication that can occur after a caesarean section. CT scans can show filling defects and an increased diameter in the affected vein. The pyloric antrum is located near the bottom of the stomach, close to the pyloric sphincter. Since the stomach is an intraperitoneal organ in the left upper quadrant, it is unlikely to be lacerated during a caesarean section. Any damage to the stomach would not result in retroperitoneal fluid accumulation.
The retroperitoneal structures are those that are located behind the peritoneum, which is the membrane that lines the abdominal cavity. These structures include the duodenum (2nd, 3rd, and 4th parts), ascending and descending colon, kidneys, ureters, aorta, and inferior vena cava. They are situated in the back of the abdominal cavity, close to the spine. In contrast, intraperitoneal structures are those that are located within the peritoneal cavity, such as the stomach, duodenum (1st part), jejunum, ileum, transverse colon, and sigmoid colon. It is important to note that the retroperitoneal structures are not well demonstrated in the diagram as the posterior aspect has been removed, but they are still significant in terms of their location and function.
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This question is part of the following fields:
- Gastrointestinal System
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Question 46
Incorrect
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A 20-year-old man presents to the gastroenterology clinic with a 5-month history of abdominal pain and diarrhoea. He reports passing fresh red blood in his stool and having up to 7 bowel movements a day in the last month. He has lost 6kg in weight over the last 5 months.
The patient is referred for various investigations.
What finding would support the probable diagnosis?Your Answer: Deep mucosal ulceration
Correct Answer: Goblet cell depletion
Explanation:Crohn’s disease has the potential to impact any section of the digestive system, including the oral mucosa and peri-anal region. It is common for there to be healthy areas of bowel in between the inflamed segments. The disease is characterized by deep ulceration in the gut mucosa, with skip lesions creating a distinctive cobblestone appearance during endoscopy.
Inflammatory bowel disease (IBD) is a condition that includes two main types: Crohn’s disease and ulcerative colitis. Although they share many similarities in terms of symptoms, diagnosis, and treatment, there are some key differences between the two. Crohn’s disease is characterized by non-bloody diarrhea, weight loss, upper gastrointestinal symptoms, mouth ulcers, perianal disease, and a palpable abdominal mass in the right iliac fossa. On the other hand, ulcerative colitis is characterized by bloody diarrhea, abdominal pain in the left lower quadrant, tenesmus, gallstones, and primary sclerosing cholangitis. Complications of Crohn’s disease include obstruction, fistula, and colorectal cancer, while ulcerative colitis has a higher risk of colorectal cancer than Crohn’s disease. Pathologically, Crohn’s disease lesions can be seen anywhere from the mouth to anus, while ulcerative colitis inflammation always starts at the rectum and never spreads beyond the ileocaecal valve. Endoscopy and radiology can help diagnose and differentiate between the two types of IBD.
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This question is part of the following fields:
- Gastrointestinal System
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Question 47
Correct
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Which of the following is the least probable outcome associated with severe atrophic gastritis in elderly patients?
Your Answer: Duodenal ulcers
Explanation:A duodenal ulcer is unlikely to occur as a result of the decrease in gastric acid. However, it should be noted that gastric polyps may develop (refer to below).
Types of Gastritis and Their Features
Gastritis is a condition characterized by inflammation of the stomach lining. There are different types of gastritis, each with its own unique features. Type A gastritis is an autoimmune condition that results in the reduction of parietal cells and hypochlorhydria. This type of gastritis is associated with circulating antibodies to parietal cells and can lead to B12 malabsorption. Type B gastritis, on the other hand, is antral gastritis that is caused by infection with Helicobacter pylori. This type of gastritis can lead to peptic ulceration and intestinal metaplasia in the stomach, which requires surveillance endoscopy.
Reflux gastritis occurs when bile refluxes into the stomach, either post-surgical or due to the failure of pyloric function. This type of gastritis is characterized by chronic inflammation and foveolar hyperplasia. Erosive gastritis is caused by agents that disrupt the gastric mucosal barrier, such as NSAIDs and alcohol. Stress ulceration occurs as a result of mucosal ischemia during hypotension or hypovolemia. The stomach is the most sensitive organ in the GI tract to ischemia following hypovolemia, and prophylaxis with acid-lowering therapy and sucralfate may minimize complications. Finally, Menetrier’s disease is a pre-malignant condition characterized by gross hypertrophy of the gastric mucosal folds, excessive mucous production, and hypochlorhydria.
In summary, gastritis is a condition that can have different types and features. It is important to identify the type of gastritis to provide appropriate management and prevent complications.
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This question is part of the following fields:
- Gastrointestinal System
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Question 48
Incorrect
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A 56-year-old woman arrives at the emergency department complaining of abdominal pain that has been ongoing for two days. The pain is diffuse, sudden in onset, and not radiating. She has a medical history of antiphospholipid syndrome but no cirrhosis.
Upon examination, the patient is visibly jaundiced and her abdomen is noticeably distended. There is painful hepatomegaly and shifting dullness. Abdominal ultrasonography confirms the presence of ascites and venous outflow obstruction.
Which vessel is the most likely culprit for the occlusion?Your Answer: Hepatic portal vein
Correct Answer: Hepatic vein
Explanation:Budd-Chiari syndrome is caused by thrombosis of the hepatic vein, resulting in symptoms such as painful hepatomegaly, jaundice, and ascites. This patient’s antiphospholipid syndrome increases their risk of thrombosis, making Budd-Chiari syndrome more likely than hepatic portal vein thrombosis. Inferior mesenteric vein thrombosis is an unlikely cause of the patient’s symptoms, while inferior vena cava thrombosis would present differently and is associated with lung malignancy.
Understanding Budd-Chiari Syndrome
Budd-Chiari syndrome, also known as hepatic vein thrombosis, is a condition that is often associated with an underlying hematological disease or another procoagulant condition. The causes of this syndrome include polycythemia rubra vera, thrombophilia, pregnancy, and the use of combined oral contraceptive pills. The symptoms of Budd-Chiari syndrome typically include sudden onset and severe abdominal pain, ascites leading to abdominal distension, and tender hepatomegaly.
To diagnose Budd-Chiari syndrome, an ultrasound with Doppler flow studies is usually the initial radiological investigation. This test is highly sensitive and can help identify the presence of the condition. It is important to diagnose and treat Budd-Chiari syndrome promptly to prevent complications such as liver failure and portal hypertension.
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This question is part of the following fields:
- Gastrointestinal System
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Question 49
Correct
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A 70-year-old woman visits her doctor as she has discovered a lump in her groin. She reports feeling well otherwise and has not experienced any changes in bowel movements or abdominal discomfort. The patient mentions that the lump tends to increase in size throughout the day, particularly when she is busy looking after her grandchildren. She has never undergone abdominal surgery. The doctor suspects a hernia and upon examination, identifies that it can be reduced and locates the hernia's neck, which is situated inferiorly and laterally to the pubic tubercle. What is the probable cause of the patient's groin lump?
Your Answer: Femoral hernia
Explanation:Femoral hernias are more prevalent in women than men, and their location at the neck of the hernia, which is inferior and lateral to the pubic tubercle, is indicative of a femoral hernia. On the other hand, an inguinal hernia would have its neck located superior and medial to the pubic tubercle, while both direct and indirect inguinal hernias share this characteristic. Since the patient has no surgical history, this cannot be an incisional hernia. A spigelian hernia, on the other hand, occurs when there is a herniation through the spigelian fascia, which is located along the semilunar line.
Understanding Inguinal Hernias
Inguinal hernias are the most common type of abdominal wall hernias, with 75% of cases falling under this category. They are more prevalent in men, with a 25% lifetime risk of developing one. The main symptom is a lump in the groin area, which disappears when pressure is applied or when the patient lies down. Discomfort and aching are also common, especially during physical activity. However, severe pain is rare, and strangulation is even rarer.
The traditional classification of inguinal hernias into indirect and direct types is no longer relevant in clinical management. Instead, the current consensus is to treat medically fit patients, even if they are asymptomatic. A hernia truss may be an option for those who are not fit for surgery, but it has limited use in other patients. Mesh repair is the preferred method, as it has the lowest recurrence rate. Unilateral hernias are usually repaired through an open approach, while bilateral and recurrent hernias are repaired laparoscopically.
After surgery, patients are advised to return to non-manual work after 2-3 weeks for open repair and 1-2 weeks for laparoscopic repair. Complications may include early bruising and wound infection, as well as late chronic pain and recurrence. It is important to seek medical attention if any of these symptoms occur.
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This question is part of the following fields:
- Gastrointestinal System
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Question 50
Incorrect
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A 65-year-old female patient presents to the gastroenterology clinic complaining of recurrent epigastric pain and acid reflux that has not responded to antacids or proton-pump inhibitors. Upon gastroscopy, an ulcer is discovered in the descending duodenum and a tumor is found in the antrum of the stomach. What type of cell is the origin of this tumor?
Your Answer: D cells
Correct Answer: G cells
Explanation:Gastrin is synthesized by the G cells located in the antrum of the stomach.
Based on the symptoms presented, it is probable that the patient has a gastrinoma. This type of tumor produces an excess of gastrin, which stimulates the production of hydrochloric acid, leading to the development of peptic ulcers. Normally, gastrin is secreted by the G cells located in the antrum of the stomach.
Other cells found in the stomach include S cells, which produce secretin, I cells, which produce CCK, and D cells, which produce somatostatin. However, there is no such cell as an H cell in the stomach.
Overview of Gastrointestinal Hormones
Gastrointestinal hormones play a crucial role in the digestion and absorption of food. These hormones are secreted by various cells in the stomach and small intestine in response to different stimuli such as the presence of food, pH changes, and neural signals.
One of the major hormones involved in food digestion is gastrin, which is secreted by G cells in the antrum of the stomach. Gastrin increases acid secretion by gastric parietal cells, stimulates the secretion of pepsinogen and intrinsic factor, and increases gastric motility. Another hormone, cholecystokinin (CCK), is secreted by I cells in the upper small intestine in response to partially digested proteins and triglycerides. CCK increases the secretion of enzyme-rich fluid from the pancreas, contraction of the gallbladder, and relaxation of the sphincter of Oddi. It also decreases gastric emptying and induces satiety.
Secretin is another hormone secreted by S cells in the upper small intestine in response to acidic chyme and fatty acids. Secretin increases the secretion of bicarbonate-rich fluid from the pancreas and hepatic duct cells, decreases gastric acid secretion, and has a trophic effect on pancreatic acinar cells. Vasoactive intestinal peptide (VIP) is a neural hormone that stimulates secretion by the pancreas and intestines and inhibits acid secretion.
Finally, somatostatin is secreted by D cells in the pancreas and stomach in response to fat, bile salts, and glucose in the intestinal lumen. Somatostatin decreases acid and pepsin secretion, decreases gastrin secretion, decreases pancreatic enzyme secretion, and decreases insulin and glucagon secretion. It also inhibits the trophic effects of gastrin and stimulates gastric mucous production.
In summary, gastrointestinal hormones play a crucial role in regulating the digestive process and maintaining homeostasis in the gastrointestinal tract.
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This question is part of the following fields:
- Gastrointestinal System
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Question 51
Correct
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An 80-year-old woman comes to the clinic complaining of fatigue, indigestion, and weight loss that has been going on for 3 months. During the examination, the doctor notices jaundice in the conjunctival sclera and mild tenderness in the right upper quadrant upon palpation. After conducting scans and biopsy, the results suggest gallbladder cancer.
What is the most likely lymph node to be the first site of metastasis for the cancer cells?Your Answer: Lund's node (cystic lymph node)
Explanation:Lund’s node serves as the first lymph node to be affected by cancer cells draining from the gallbladder, making it the sentinel lymph node for this organ. This suggests that Lund’s node is the primary target for metastasis in gallbladder cancer.
Cloquet’s node is classified as one of the deep inguinal nodes, while Virchow’s node is a sentinel lymph node located on the left supraclavicular region. Virchow’s node is associated with certain abdominal cancers, such as gastric cancer.
Peyer’s patches are clusters of lymphoid follicles that can be found throughout the ileum.
The gallbladder is a sac made of fibromuscular tissue that can hold up to 50 ml of fluid. Its lining is made up of columnar epithelium. The gallbladder is located in close proximity to various organs, including the liver, transverse colon, and the first part of the duodenum. It is covered by peritoneum and is situated between the right lobe and quadrate lobe of the liver. The gallbladder receives its arterial supply from the cystic artery, which is a branch of the right hepatic artery. Its venous drainage is directly to the liver, and its lymphatic drainage is through Lund’s node. The gallbladder is innervated by both sympathetic and parasympathetic nerves. The common bile duct originates from the confluence of the cystic and common hepatic ducts and is located in the hepatobiliary triangle, which is bordered by the common hepatic duct, cystic duct, and the inferior edge of the liver. The cystic artery is also found within this triangle.
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This question is part of the following fields:
- Gastrointestinal System
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Question 52
Correct
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A 25-year-old male has been referred to the clinic due to a family history of colorectal cancer. Genetic testing revealed a mutation of the APC gene, and a colonoscopy is recommended. What is the probable outcome of the procedure?
Your Answer: Multiple colonic adenomas
Explanation:Familial adenomatous polyposis coli is characterized by the presence of multiple colonic adenomas, which are caused by mutations in the APC gene.
Polyposis syndromes are a group of genetic disorders that cause the development of multiple polyps in the colon and other parts of the gastrointestinal tract. These polyps can increase the risk of developing cancer, and therefore, early detection and management are crucial. There are several types of polyposis syndromes, each with its own genetic defect, features, and associated disorders.
Familial adenomatous polyposis (FAP) is caused by a mutation in the APC gene and is characterized by the development of over 100 colonic adenomas, with a 100% risk of cancer. Screening and management involve regular colonoscopies and resectional surgery if polyps are found. FAP is also associated with gastric and duodenal polyps and abdominal desmoid tumors.
MYH-associated polyposis is caused by a biallelic mutation of the MYH gene and is associated with multiple colonic polyps and an increased risk of right-sided cancers. Attenuated phenotype can be managed with regular colonoscopies, while resection and ileoanal pouch reconstruction are recommended for those with multiple polyps.
Peutz-Jeghers syndrome is caused by a mutation in the STK11 gene and is characterized by multiple benign intestinal hamartomas, episodic obstruction, and an increased risk of GI cancers. Screening involves annual examinations and pan-intestinal endoscopy every 2-3 years.
Cowden disease is caused by a mutation in the PTEN gene and is characterized by macrocephaly, multiple intestinal hamartomas, and an increased risk of cancer at any site. Targeted individualized screening is recommended, with extra surveillance for breast, thyroid, and uterine cancers.
HNPCC (Lynch syndrome) is caused by germline mutations of DNA mismatch repair genes and is associated with an increased risk of colorectal, endometrial, and gastric cancers. Colonoscopies every 1-2 years from age 25 and consideration of prophylactic surgery are recommended, along with extra colonic surveillance.
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This question is part of the following fields:
- Gastrointestinal System
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Question 53
Correct
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Samantha is an 80-year-old woman who has been experiencing painless obstructive jaundice. Upon investigation, a malignancy is discovered. The surgeon recommends a Whipple's procedure to remove the malignancy.
What type of malignancy is the most probable diagnosis?Your Answer: Adenocarcinoma
Explanation:Ductal adenocarcinoma is the most frequently occurring type of pancreatic cancer, particularly in the head of the pancreas. Endocrine tumors of the pancreas are uncommon.
Pancreatic cancer is a type of cancer that is often diagnosed late due to its non-specific symptoms. The majority of pancreatic tumors are adenocarcinomas and are typically found in the head of the pancreas. Risk factors for pancreatic cancer include increasing age, smoking, diabetes, chronic pancreatitis, hereditary non-polyposis colorectal carcinoma, and mutations in the BRCA2 and KRAS genes.
Symptoms of pancreatic cancer can include painless jaundice, pale stools, dark urine, and pruritus. Courvoisier’s law states that a palpable gallbladder is unlikely to be due to gallstones in the presence of painless obstructive jaundice. However, patients often present with non-specific symptoms such as anorexia, weight loss, and epigastric pain. Loss of exocrine and endocrine function can also occur, leading to steatorrhea and diabetes mellitus. Atypical back pain and migratory thrombophlebitis (Trousseau sign) are also common.
Ultrasound has a sensitivity of around 60-90% for detecting pancreatic cancer, but high-resolution CT scanning is the preferred diagnostic tool. The ‘double duct’ sign, which is the simultaneous dilatation of the common bile and pancreatic ducts, may be seen on imaging.
Less than 20% of patients with pancreatic cancer are suitable for surgery at the time of diagnosis. A Whipple’s resection (pancreaticoduodenectomy) may be performed for resectable lesions in the head of the pancreas, but side-effects such as dumping syndrome and peptic ulcer disease can occur. Adjuvant chemotherapy is typically given following surgery, and ERCP with stenting may be used for palliation.
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This question is part of the following fields:
- Gastrointestinal System
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Question 54
Correct
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A 68-year-old man is having his left kidney and ureter removed. During the surgery, the surgeons remove the ureter. What provides the blood supply to the upper part of the ureter?
Your Answer: Branches of the renal artery
Explanation:The renal artery provides branches that supply the proximal ureter, while other feeding vessels are described in the following.
Anatomy of the Ureter
The ureter is a muscular tube that measures 25-35 cm in length and is lined by transitional epithelium. It is surrounded by a thick muscular coat that becomes three muscular layers as it crosses the bony pelvis. This retroperitoneal structure overlies the transverse processes L2-L5 and lies anterior to the bifurcation of iliac vessels. The blood supply to the ureter is segmental and includes the renal artery, aortic branches, gonadal branches, common iliac, and internal iliac. It is important to note that the ureter lies beneath the uterine artery.
In summary, the ureter is a vital structure in the urinary system that plays a crucial role in transporting urine from the kidneys to the bladder. Its unique anatomy and blood supply make it a complex structure that requires careful consideration in any surgical or medical intervention.
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This question is part of the following fields:
- Gastrointestinal System
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Question 55
Correct
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As an observer in the colorectal surgical department, you spend a morning watching a colonoscopy list. A number of patients who arrive during the morning are individuals with Hereditary Non-Polyposis Colorectal Cancer (HNPCC), who are being screened to detect any early signs of colorectal cancer. What is the lifetime risk of developing colorectal cancer for individuals with this condition?
Your Answer: 90%
Explanation:Colorectal cancer can be classified into three types: sporadic, hereditary non-polyposis colorectal carcinoma (HNPCC), and familial adenomatous polyposis (FAP). Sporadic colon cancer is believed to be caused by a series of genetic mutations, including allelic loss of the APC gene, activation of the K-ras oncogene, and deletion of p53 and DCC tumor suppressor genes. HNPCC, which is an autosomal dominant condition, is the most common form of inherited colon cancer. It is caused by mutations in genes involved in DNA mismatch repair, leading to microsatellite instability. The most common genes affected are MSH2 and MLH1. Patients with HNPCC are also at a higher risk of other cancers, such as endometrial cancer. The Amsterdam criteria are sometimes used to aid diagnosis of HNPCC. FAP is a rare autosomal dominant condition that leads to the formation of hundreds of polyps by the age of 30-40 years. It is caused by a mutation in the APC gene. Patients with FAP are also at risk of duodenal tumors. A variant of FAP called Gardner’s syndrome can also feature osteomas of the skull and mandible, retinal pigmentation, thyroid carcinoma, and epidermoid cysts on the skin. Genetic testing can be done to diagnose HNPCC and FAP, and patients with FAP generally have a total colectomy with ileo-anal pouch formation in their twenties.
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This question is part of the following fields:
- Gastrointestinal System
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Question 56
Incorrect
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A 32-year-old woman presents with a 14-day history of profuse, watery diarrhoea. She denies the presence of blood. There is no history of recent travel. The diarrhoea is stopping her from going to work, and so she has been forced to take unpaid leave. She wants to return to work as she is the sole breadwinner for the family.
On examination, she is apyrexial but looks clinically dehydrated.
After ruling out infection and inflammatory bowel disease, you prescribe a short course of loperamide to help slow down her bowel movements.
What is the mechanism of action of the prescribed anti-diarrhoeal medication?Your Answer: Antagonist of μ-opioid receptors in the myenteric plexus of the large intestine
Correct Answer: Agonist of μ-opioid receptors in the myenteric plexus of the large intestine
Explanation:The myenteric plexus of the large intestine’s μ-opioid receptors are targeted by loperamide.
Antidiarrhoeal Agents: Opioid Agonists
Antidiarrhoeal agents are medications used to treat diarrhoea. Opioid agonists are a type of antidiarrhoeal agent that work by slowing down the movement of the intestines, which reduces the frequency and urgency of bowel movements. Two common opioid agonists used for this purpose are loperamide and diphenoxylate.
Loperamide is available over-the-counter and is often used to treat acute diarrhoea. It works by binding to opioid receptors in the intestines, which reduces the contractions of the muscles in the intestinal wall. This slows down the movement of food and waste through the intestines, allowing more time for water to be absorbed and resulting in firmer stools.
Diphenoxylate is a prescription medication that is often used to treat chronic diarrhoea. It works in a similar way to loperamide, but is often combined with atropine to discourage abuse and overdose.
Overall, opioid agonists are effective at treating diarrhoea, but should be used with caution and under the guidance of a healthcare professional. They can cause side effects such as constipation, dizziness, and nausea, and may interact with other medications.
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This question is part of the following fields:
- Gastrointestinal System
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Question 57
Correct
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A 67-year-old man arrives at the emergency department complaining of acute abdominal pain and diarrhoea that started 3 hours ago. Upon examination, his pulse is 105 bpm, blood pressure is 98/70 mmHg, and temperature is 37.5 ºC. The abdominal examination reveals diffuse tenderness with rebound and guarding. The X-ray shows thumbprinting, leading you to suspect that he may have ischaemic colitis. Which specific area is the most probable site of involvement?
Your Answer: Splenic flexure
Explanation:Ischemic colitis is a condition where blood flow to a part of the large intestine is temporarily reduced, often due to a blockage or hypo-perfusion. While any part of the colon can be affected, it most commonly affects the left side. The hepatic flexure, located on the right side of the colon, is less likely to be involved as it has a good blood supply from the superior mesenteric artery (SMA). The ileocecal junction is also less likely to be affected as it has a good blood supply from the ileocolic artery, a branch of the SMA. The splenic flexure, located between the left colon and the transverse colon, is the most likely area to be affected by ischaemic colitis as it is a watershed area supplied by the inferior mesenteric artery. The sigmoid colon, supplied by the sigmoidal branches of the inferior mesenteric artery, is less likely to be affected. The recto-sigmoid junction is also a watershed area and vulnerable to ischaemic colitis, but it is less common than ischaemia at the splenic flexure.
Ischaemia to the lower gastrointestinal tract can result in acute mesenteric ischaemia, chronic mesenteric ischaemia, and ischaemic colitis. Common predisposing factors include increasing age, atrial fibrillation, other causes of emboli, cardiovascular disease risk factors, and cocaine use. Common features include abdominal pain, rectal bleeding, diarrhea, fever, and elevated white blood cell count with lactic acidosis. CT is the investigation of choice. Acute mesenteric ischaemia is typically caused by an embolism and requires urgent surgery. Chronic mesenteric ischaemia presents with intermittent abdominal pain. Ischaemic colitis is an acute but transient compromise in blood flow to the large bowel and may require surgery in a minority of cases.
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This question is part of the following fields:
- Gastrointestinal System
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Question 58
Correct
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A 30-year-old male presents to his general practitioner complaining of jaundice and fatigue that has been present for the past 2 days. He mentions that he has experienced similar symptoms in the past but has never sought medical attention until now. He reports having a severe case of the flu recently. The patient has no significant medical history and leads a healthy lifestyle, abstaining from alcohol and smoking.
What enzyme deficiency is likely responsible for this condition?Your Answer: UDP glucuronosyltransferase
Explanation:Individuals with Gilbert’s syndrome exhibit a decrease in the amount of UDP glucuronosyltransferase, an enzyme responsible for conjugating bilirubin in the liver. This deficiency leads to an accumulation of unconjugated bilirubin, which cannot be eliminated through urine, resulting in jaundice. Although symptoms may arise during periods of stress, the condition is generally not clinically significant.
HMG-CoA reductase is an enzyme involved in cholesterol synthesis, while lipoprotein lipase plays a central role in lipid metabolism and is associated with various conditions such as hypertriglyceridemia. G6PD deficiency, on the other hand, affects the pentose phosphate pathway by reducing the production of NADPH.
Gilbert’s syndrome is a genetic disorder that affects the way bilirubin is processed in the body. It is caused by a deficiency of UDP glucuronosyltransferase, which leads to unconjugated hyperbilirubinemia. This means that bilirubin is not properly broken down and eliminated from the body, resulting in jaundice. However, jaundice may only be visible during certain conditions such as fasting, exercise, or illness. The prevalence of Gilbert’s syndrome is around 1-2% in the general population.
To diagnose Gilbert’s syndrome, doctors may look for a rise in bilirubin levels after prolonged fasting or the administration of IV nicotinic acid. However, treatment is not necessary for this condition. While the exact mode of inheritance is still debated, it is known to be an autosomal recessive disorder.
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This question is part of the following fields:
- Gastrointestinal System
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Question 59
Correct
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Liam, who is also suffering from chronic pancreatitis, undergoes a distal pancreatectomy. During a post-surgery consultation, he expresses his concern to the doctor about the possibility of experiencing poor food digestion after the operation, as he has read about others who have had the same issue. What measures can the doctor take to prevent this from happening to Liam?
Your Answer: Prescribe pancreatic enzymes (e.g. Creon)
Explanation:To aid digestion of food in patients with chronic pancreatitis, the management plan includes the replacement of pancreatic enzymes such as Creon. Inadequacy of pancreatic enzymes due to pancreatic surgery can also lead to poor digestion of food, which can be prevented by providing patients with pancreatic enzyme supplements like Creon. However, proton pump inhibitors or probiotics are not effective in replacing pancreatic enzymes. Fiona does not require a low fibre diet.
Understanding Chronic Pancreatitis
Chronic pancreatitis is a condition characterized by inflammation that can affect both the exocrine and endocrine functions of the pancreas. While alcohol excess is the leading cause of this condition, up to 20% of cases are unexplained. Other causes include genetic factors such as cystic fibrosis and haemochromatosis, as well as ductal obstruction due to tumors, stones, and structural abnormalities.
Symptoms of chronic pancreatitis include pain that worsens 15 to 30 minutes after a meal, steatorrhoea, and diabetes mellitus. Abdominal x-rays and CT scans are used to detect pancreatic calcification, which is present in around 30% of cases. Functional tests such as faecal elastase may also be used to assess exocrine function if imaging is inconclusive.
Management of chronic pancreatitis involves pancreatic enzyme supplements, analgesia, and antioxidants. While there is limited evidence to support the use of antioxidants, one study suggests that they may be beneficial in early stages of the disease. Overall, understanding the causes and symptoms of chronic pancreatitis is crucial for effective management and treatment.
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This question is part of the following fields:
- Gastrointestinal System
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Question 60
Correct
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An 80-year-old man presents to the emergency department with severe abdominal pain and haematochezia. The patient localises the pain to the umbilical region. He has a past medical history of atrial fibrillation, stroke and is currently being treated for multiple myeloma.
His observations show a heart rate of 122/min, a respiratory rate of 29/min, a blood pressure of 119/93 mmHg, an O2 saturation of 97%, and a temperature of 38.2 ºC. His chest is clear. Abdominal examination identify some mild tenderness with no guarding. An abdominal bruit is heard on auscultation.
Which segment of the gastrointestinal tract is commonly affected in this condition?Your Answer: Splenic flexure
Explanation:Ischaemic colitis most frequently affects the splenic flexure.
Understanding Ischaemic Colitis
Ischaemic colitis is a condition that occurs when there is a temporary reduction in blood flow to the large bowel. This can cause inflammation, ulcers, and bleeding. The condition is more likely to occur in areas of the bowel that are located at the borders of the territory supplied by the superior and inferior mesenteric arteries, such as the splenic flexure.
When investigating ischaemic colitis, doctors may look for a sign called thumbprinting on an abdominal x-ray. This occurs due to mucosal edema and hemorrhage. It is important to diagnose and treat ischaemic colitis promptly to prevent complications and ensure a full recovery.
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This question is part of the following fields:
- Gastrointestinal System
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Question 61
Correct
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A 72-year-old female presents to her local physician complaining of general fatigue and tiredness. She reports no fever, night sweats, or weight loss. She maintains an active lifestyle and attends fitness classes weekly. Her medical history includes hypertension, type II diabetes mellitus, constipation, and depression.
The physician orders blood tests, and the results are as follows:
- Hb: 113 g/l
- Platelets: 239 * 109/l
- WBC: 6 * 109/l
- Neuts: 2 * 109/l
- Lymphs: 2 * 109/l
- Eosin: 0.3 * 109/l
- Na+: 142 mmol/l
- K+: 3.2 mmol/l
- Bilirubin: 12 µmol/l
- ALP: 23 u/l
- ALT: 10 u/l
- γGT: 23 u/l
- Urea: 4 mmol/l
- Creatinine: 50 µmol/l
- Albumin: 30 g/l
Which medication is most likely causing her symptoms?Your Answer: Senna
Explanation:Prolonged use of senna increases the risk of hypokalemia, which is evident in the patient’s blood results. The symptoms of mild hypokalemia are non-specific and include fatigue, muscle weakness, constipation, and rhabdomyolysis. Given the patient’s medical history of constipation, it is likely that she has been taking a laxative, which could be either osmotic or a stimulant. Both types of laxatives are known to cause hypokalemia, and in this case, senna is the likely culprit.
Heparin can cause hyperkalemia, especially when used in conjunction with spironolactone, ACE inhibitors, non-steroidal anti-inflammatory drugs, and trimethoprim. Heparin inhibits aldosterone synthesis, leading to increased potassium retention and sodium excretion. This effect is more pronounced in elderly individuals, diabetics, and those with renal failure. The risk of hyperkalemia increases with higher doses, prolonged use, and unfractionated heparin therapy.
Amiloride is a potassium-sparing diuretic that works by inhibiting sodium reabsorption in the kidneys. It promotes the loss of sodium and water from the body without depleting potassium. Amiloride causes hyperkalemia by inhibiting sodium reabsorption at various points in the kidneys, which reduces potassium and hydrogen secretion and subsequent excretion.
Losartan is an angiotensin II receptor blocker that is known to cause hyperkalemia and is therefore not the cause of the patient’s hypokalemia.
Understanding Laxatives
Laxatives are frequently prescribed medications in clinical practice, with constipation being a common issue among patients. While constipation may be a symptom of underlying pathology, many patients experience simple idiopathic constipation. The British National Formulary (BNF) categorizes laxatives into four groups: osmotic, stimulant, bulk-forming, and faecal softeners.
Osmotic laxatives, such as lactulose, macrogols, and rectal phosphates, work by drawing water into the bowel to soften stools and promote bowel movements. Stimulant laxatives, including senna, docusate, bisacodyl, and glycerol, stimulate the muscles in the bowel to contract and move stool along. Co-danthramer, a combination of a stimulant and a bulk-forming laxative, should only be prescribed to palliative patients due to its potential carcinogenic effects.
Bulk-forming laxatives, such as ispaghula husk and methylcellulose, work by increasing the bulk of stool and promoting regular bowel movements. Faecal softeners, such as arachis oil enemas, are not commonly prescribed but can be used to soften stool and ease bowel movements.
In summary, understanding the different types of laxatives and their mechanisms of action can help healthcare professionals prescribe the most appropriate treatment for patients experiencing constipation.
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This question is part of the following fields:
- Gastrointestinal System
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Question 62
Correct
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A 58-year-old woman presents to the colorectal clinic with complaints of pruritus ani. During the examination, a polypoidal mass is discovered below the dentate line. A biopsy confirms the presence of squamous cell carcinoma. Which lymph node groups are at risk of metastasis from this lesion?
Your Answer: Inguinal
Explanation:If there are any injuries or abnormalities located beyond the dentate line, they will be drained towards the inguinal nodes. In some cases, this may require a block dissection of the groin.
Anatomy of the Rectum
The rectum is a capacitance organ that measures approximately 12 cm in length. It consists of both intra and extraperitoneal components, with the transition from the sigmoid colon marked by the disappearance of the tenia coli. The extra peritoneal rectum is surrounded by mesorectal fat that contains lymph nodes, which are removed during rectal cancer surgery. The fascial layers that surround the rectum are important clinical landmarks, with the fascia of Denonvilliers located anteriorly and Waldeyers fascia located posteriorly.
In males, the rectum is adjacent to the rectovesical pouch, bladder, prostate, and seminal vesicles, while in females, it is adjacent to the recto-uterine pouch (Douglas), cervix, and vaginal wall. Posteriorly, the rectum is in contact with the sacrum, coccyx, and middle sacral artery, while laterally, it is adjacent to the levator ani and coccygeus muscles.
The superior rectal artery supplies blood to the rectum, while the superior rectal vein drains it. Mesorectal lymph nodes located superior to the dentate line drain into the internal iliac and then para-aortic nodes, while those located inferior to the dentate line drain into the inguinal nodes. Understanding the anatomy of the rectum is crucial for surgical procedures and the diagnosis and treatment of rectal diseases.
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This question is part of the following fields:
- Gastrointestinal System
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Question 63
Correct
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A 25-year-old female has received a pan proctocolectomy and ileoanal pouch due to familial adenomatous polyposis coli. What is the most frequent non-colonic manifestation of this condition?
Your Answer: Duodenal polyps
Explanation:Polyposis syndromes are a group of genetic disorders that cause the development of multiple polyps in the colon and other parts of the gastrointestinal tract. These polyps can increase the risk of developing cancer, and therefore, early detection and management are crucial. There are several types of polyposis syndromes, each with its own genetic defect, features, and associated disorders.
Familial adenomatous polyposis (FAP) is caused by a mutation in the APC gene and is characterized by the development of over 100 colonic adenomas, with a 100% risk of cancer. Screening and management involve regular colonoscopies and resectional surgery if polyps are found. FAP is also associated with gastric and duodenal polyps and abdominal desmoid tumors.
MYH-associated polyposis is caused by a biallelic mutation of the MYH gene and is associated with multiple colonic polyps and an increased risk of right-sided cancers. Attenuated phenotype can be managed with regular colonoscopies, while resection and ileoanal pouch reconstruction are recommended for those with multiple polyps.
Peutz-Jeghers syndrome is caused by a mutation in the STK11 gene and is characterized by multiple benign intestinal hamartomas, episodic obstruction, and an increased risk of GI cancers. Screening involves annual examinations and pan-intestinal endoscopy every 2-3 years.
Cowden disease is caused by a mutation in the PTEN gene and is characterized by macrocephaly, multiple intestinal hamartomas, and an increased risk of cancer at any site. Targeted individualized screening is recommended, with extra surveillance for breast, thyroid, and uterine cancers.
HNPCC (Lynch syndrome) is caused by germline mutations of DNA mismatch repair genes and is associated with an increased risk of colorectal, endometrial, and gastric cancers. Colonoscopies every 1-2 years from age 25 and consideration of prophylactic surgery are recommended, along with extra colonic surveillance.
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This question is part of the following fields:
- Gastrointestinal System
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Question 64
Correct
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A 56-year-old female patient who underwent tubal ligation presents to her general practitioner with complaints of abdominal pain, flank pain, visible blood in her urine, and involuntary urinary leakage. She has a history of lithotripsy for renal calculi one year ago. A CT scan of her abdomen and pelvis reveals an intra-abdominal fluid collection. What is the most probable diagnosis?
Your Answer: Ureter injury
Explanation:The patient’s symptoms and CT findings suggest that they may have suffered iatrogenic damage to their ureters, which are retroperitoneal organs. This can lead to fluid accumulation in the retroperitoneal space, causing haematuria, abdominal/flank pain, and incontinence. While calculi and lithotripsy can damage the ureter mucosal lining, they are unlikely to have caused fluid accumulation in the intra-abdominal cavity, especially since the lithotripsy was performed a year ago. Pelvic inflammatory disease and urinary tract infections can cause similar symptoms, but their CT findings would be different.
The retroperitoneal structures are those that are located behind the peritoneum, which is the membrane that lines the abdominal cavity. These structures include the duodenum (2nd, 3rd, and 4th parts), ascending and descending colon, kidneys, ureters, aorta, and inferior vena cava. They are situated in the back of the abdominal cavity, close to the spine. In contrast, intraperitoneal structures are those that are located within the peritoneal cavity, such as the stomach, duodenum (1st part), jejunum, ileum, transverse colon, and sigmoid colon. It is important to note that the retroperitoneal structures are not well demonstrated in the diagram as the posterior aspect has been removed, but they are still significant in terms of their location and function.
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This question is part of the following fields:
- Gastrointestinal System
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Question 65
Correct
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A slender 65-year-old woman complains of sudden onset of abdominal pain. The pain is diffuse but most severe in the upper abdomen. During examination, she is intentionally tensing her muscles and experiences extreme tenderness upon palpation. She has a medical history of left hip osteoarthritis, which she is treating with pain medication. Your coworker requests that you examine her chest x-ray while standing. What is the probable result in this situation?
Your Answer: Free air under the diaphragm
Explanation:It is probable that this woman is suffering from a perforated peptic ulcer, given her medical history of osteoarthritis and use of analgesics (possibly NSAIDs) which can lead to ulcer development. The presence of free air under the diaphragm on an upright chest x-ray is a typical indication of a perforated organ, indicating the presence of pneumoperitoneum (air in the peritoneal cavity).
Exam Features of Conditions Causing Abdominal Pain
Abdominal pain can be caused by various conditions, and it is important for medical students to be familiar with the characteristic exam features of each condition. Peptic ulcer disease, for example, can present with epigastric pain that is either relieved or worsened by eating, depending on whether it is a duodenal or gastric ulcer. Appendicitis, on the other hand, typically starts with pain in the central abdomen before localizing to the right iliac fossa. Other conditions, such as acute pancreatitis, biliary colic, diverticulitis, and intestinal obstruction, also have their own unique exam features.
It is worth noting that some conditions causing abdominal pain may not be as common or may have unusual presentations. For instance, acute coronary syndrome, diabetic ketoacidosis, pneumonia, acute intermittent porphyria, and lead poisoning can all cause abdominal pain, but they are not typically associated with it. Therefore, it is important for medical students to have a broad understanding of the possible causes of abdominal pain and to be able to recognize the characteristic exam features of each condition.
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This question is part of the following fields:
- Gastrointestinal System
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Question 66
Incorrect
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A 65-year-old man visits his GP complaining of a lump in his groin. He reports no other symptoms such as abdominal pain or changes in bowel habits. Upon examination, the GP notes that the lump is soft and can be reduced without causing discomfort to the patient. The GP suspects an inguinal hernia but is unsure if it is direct or indirect. To determine this, the GP reduces the lump and applies pressure to the anatomical landmark for the deep inguinal ring. What is this landmark?
Your Answer: Superior to the mid inguinal point
Correct Answer: Superior to the midpoint of the inguinal ligament
Explanation:The inguinal canal is located above the inguinal ligament and measures 4 cm in length. Its superficial ring is situated in front of the pubic tubercle, while the deep ring is found about 1.5-2 cm above the halfway point between the anterior superior iliac spine and the pubic tubercle. The canal is bounded by the external oblique aponeurosis, inguinal ligament, lacunar ligament, internal oblique, transversus abdominis, external ring, and conjoint tendon. In males, the canal contains the spermatic cord and ilioinguinal nerve, while in females, it houses the round ligament of the uterus and ilioinguinal nerve.
The boundaries of Hesselbach’s triangle, which are frequently tested, are located in the inguinal region. Additionally, the inguinal canal is closely related to the vessels of the lower limb, which should be taken into account when repairing hernial defects in this area.
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This question is part of the following fields:
- Gastrointestinal System
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Question 67
Correct
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A 21-year-old man presents to the gastroenterology clinic with a 10-week history of abdominal pain and tenesmus. He reports experiencing intermittent diarrhea that has been increasing in frequency and has noticed fresh red blood on wiping. During the examination, he exhibits generalized abdominal tenderness, which is most severe when palpating the left iliac fossa. Several tests are ordered.
What is a characteristic finding associated with his underlying condition?Your Answer: Mucosal inflammation
Explanation:Patients with UC have a deficient mucous layer and reduced goblet cell production, while those with Crohn’s disease exhibit an increase in goblet cells. Additionally, Crohn’s disease may present with rose-thorn ulcers in the terminal ileum after a barium swallow, which manifest as deep linear ulcers.
Inflammatory bowel disease (IBD) is a condition that includes two main types: Crohn’s disease and ulcerative colitis. Although they share many similarities in terms of symptoms, diagnosis, and treatment, there are some key differences between the two. Crohn’s disease is characterized by non-bloody diarrhea, weight loss, upper gastrointestinal symptoms, mouth ulcers, perianal disease, and a palpable abdominal mass in the right iliac fossa. On the other hand, ulcerative colitis is characterized by bloody diarrhea, abdominal pain in the left lower quadrant, tenesmus, gallstones, and primary sclerosing cholangitis. Complications of Crohn’s disease include obstruction, fistula, and colorectal cancer, while ulcerative colitis has a higher risk of colorectal cancer than Crohn’s disease. Pathologically, Crohn’s disease lesions can be seen anywhere from the mouth to anus, while ulcerative colitis inflammation always starts at the rectum and never spreads beyond the ileocaecal valve. Endoscopy and radiology can help diagnose and differentiate between the two types of IBD.
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This question is part of the following fields:
- Gastrointestinal System
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Question 68
Correct
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A 57-year-old male presents to his GP with a three-month history of abdominal discomfort. He reports feeling bloated all the time, with increased flatulence. He occasionally experiences more severe symptoms, such as profuse malodorous diarrhoea and vomiting.
Upon examination, the GP notes aphthous ulceration and conjunctival pallor. The patient undergoes several blood tests and is referred for a duodenal biopsy.
The following test results are returned:
Hb 110 g/L Male: (135-180)
Female: (115 - 160)
MCV 92 fl (80-100)
Platelets 320 * 109/L (150 - 400)
WBC 7.5 * 109/L (4.0 - 11.0)
Ferritin 12 ng/mL (20 - 230)
Vitamin B12 200 ng/L (200 - 900)
Folate 2.5 nmol/L (> 3.0)
Transglutaminase IgA antibody 280 u/ml (<100)
Ca125 18 u/ml (<35)
Based on the likely diagnosis, what would be the expected finding on biopsy?Your Answer: Villous atrophy
Explanation:Coeliac disease is characterized by villous atrophy, which leads to malabsorption. This patient’s symptoms are typical of coeliac disease, which can affect both males and females in their 50s. Patients often experience non-specific abdominal discomfort for several months, similar to irritable bowel syndrome, and may not notice correlations between symptoms and specific dietary components like gluten.
Aphthous ulceration is a common sign of coeliac disease, and patients may also experience nutritional deficiencies such as iron and folate deficiency due to malabsorption. Histology will reveal villous atrophy and crypt hyperplasia. Iron and folate deficiency can lead to a normocytic anaemia and conjunctival pallor. Positive anti-transglutaminase antibodies are specific for coeliac disease.
Ulcerative colitis is characterized by crypt abscess and mucosal ulcers, while Crohn’s disease is associated with non-caseating granulomas and full-thickness inflammation. These inflammatory bowel diseases typically present in patients in their 20s and may have systemic and extraintestinal features. Anti-tTG will not be positive in IBD. Ovarian cancer is an important differential diagnosis for females over 40 with symptoms similar to irritable bowel syndrome.
Understanding Coeliac Disease
Coeliac disease is an autoimmune disorder that affects approximately 1% of the UK population. It is caused by sensitivity to gluten, a protein found in wheat, barley, and rye. Repeated exposure to gluten leads to villous atrophy, which causes malabsorption. Coeliac disease is associated with various conditions, including dermatitis herpetiformis and autoimmune disorders such as type 1 diabetes mellitus and autoimmune hepatitis. It is strongly linked to HLA-DQ2 and HLA-DQ8.
To diagnose coeliac disease, NICE recommends screening patients who exhibit signs and symptoms such as chronic or intermittent diarrhea, failure to thrive or faltering growth in children, persistent or unexplained gastrointestinal symptoms, prolonged fatigue, recurrent abdominal pain, sudden or unexpected weight loss, unexplained anemia, autoimmune thyroid disease, dermatitis herpetiformis, irritable bowel syndrome, type 1 diabetes, and first-degree relatives with coeliac disease.
Complications of coeliac disease include anemia, hyposplenism, osteoporosis, osteomalacia, lactose intolerance, enteropathy-associated T-cell lymphoma of the small intestine, subfertility, and unfavorable pregnancy outcomes. In rare cases, it can lead to esophageal cancer and other malignancies.
The diagnosis of coeliac disease is confirmed through a duodenal biopsy, which shows complete atrophy of the villi with flat mucosa and marked crypt hyperplasia, intraepithelial lymphocytosis, and dense mixed inflammatory infiltrate in the lamina propria. Treatment involves a lifelong gluten-free diet.
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This question is part of the following fields:
- Gastrointestinal System
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Question 69
Correct
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A 27-year-old man is stabbed in the groin and the area within the femoral triangle needs to be examined. What forms the lateral wall of the femoral triangle?
Your Answer: Sartorius
Explanation:Understanding the Anatomy of the Femoral Triangle
The femoral triangle is an important anatomical region located in the upper thigh. It is bounded by the inguinal ligament superiorly, the sartorius muscle laterally, and the adductor longus muscle medially. The floor of the femoral triangle is made up of the iliacus, psoas major, adductor longus, and pectineus muscles, while the roof is formed by the fascia lata and superficial fascia. The superficial inguinal lymph nodes and the long saphenous vein are also found in this region.
The femoral triangle contains several important structures, including the femoral vein, femoral artery, femoral nerve, deep and superficial inguinal lymph nodes, lateral cutaneous nerve, great saphenous vein, and femoral branch of the genitofemoral nerve. The femoral artery can be palpated at the mid inguinal point, making it an important landmark for medical professionals.
Understanding the anatomy of the femoral triangle is important for medical professionals, as it is a common site for procedures such as venipuncture, arterial puncture, and nerve blocks. It is also important for identifying and treating conditions that affect the structures within this region, such as femoral hernias and lymphadenopathy.
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This question is part of the following fields:
- Gastrointestinal System
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Question 70
Correct
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A 56-year-old woman presents with profuse diarrhoea one week after undergoing a cholecystectomy. The surgery was uncomplicated, except for a minor bile spillage during gallbladder removal. What is the probable diagnosis?
Your Answer: Clostridium difficile infection
Explanation:Broad spectrum antibiotics are only given during a cholecystectomy if there is intraoperative bile spillage. It is not standard practice to administer antibiotics for an uncomplicated procedure. Surgeons typically address any bile spills during the operation, which greatly reduces the risk of delayed pelvic abscesses. As a result, such abscesses are very uncommon.
Clostridium difficile is a type of bacteria that is commonly found in hospitals. It produces a toxin that can damage the intestines and cause a condition called pseudomembranous colitis. This bacteria usually develops when the normal gut flora is disrupted by broad-spectrum antibiotics, with second and third generation cephalosporins being the leading cause. Other risk factors include the use of proton pump inhibitors. Symptoms of C. difficile infection include diarrhea, abdominal pain, and a raised white blood cell count. The severity of the infection can be determined using the Public Health England severity scale.
To diagnose C. difficile infection, a stool sample is tested for the presence of the C. difficile toxin. Treatment involves reviewing current antibiotic therapy and stopping antibiotics if possible. For a first episode of infection, oral vancomycin is the first-line therapy for 10 days, followed by oral fidaxomicin as second-line therapy and oral vancomycin with or without IV metronidazole as third-line therapy. Recurrent infections may require different treatment options, such as oral fidaxomicin within 12 weeks of symptom resolution or oral vancomycin or fidaxomicin after 12 weeks of symptom resolution. In life-threatening cases, oral vancomycin and IV metronidazole may be used, and surgery may be considered with specialist advice. Other therapies, such as bezlotoxumab and fecal microbiota transplant, may also be considered for preventing recurrences in certain cases.
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This question is part of the following fields:
- Gastrointestinal System
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Question 71
Correct
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A 54-year-old African American male is being consented for an endoscopic retrograde cholangiopancreatography (ERCP). He is very anxious about the procedure and requests for more information about the common complications of ERCP. He is concerned about peritonitis, which usually occurs secondary to a perforation of the bowel - a rare complication of ERCP. You reassure him that perforation of the bowel, although a very serious complication, is uncommon. However, they are other more common complications of ERCP that he should be aware of.
What is the most common complication of ERCP?Your Answer: Acute pancreatitis
Explanation:The most frequent complication of ERCP is acute pancreatitis, which occurs when the X-ray contrast material or cannula irritates the pancreatic duct. While other complications may arise from ERCP, they are not as prevalent as acute pancreatitis.
Acute pancreatitis is a condition that is primarily caused by gallstones and alcohol consumption in the UK. However, there are other factors that can contribute to the development of this condition. A popular mnemonic used to remember these factors is GET SMASHED, which stands for gallstones, ethanol, trauma, steroids, mumps, autoimmune diseases, scorpion venom, hypertriglyceridaemia, hyperchylomicronaemia, hypercalcaemia, hypothermia, ERCP, and certain drugs. It is important to note that pancreatitis is seven times more common in patients taking mesalazine than sulfasalazine. CT scans can show diffuse parenchymal enlargement with oedema and indistinct margins in patients with acute pancreatitis.
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This question is part of the following fields:
- Gastrointestinal System
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Question 72
Correct
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A 54-year-old man undergoes an abdomino-perineal excision of the colon and rectum and is now experiencing impotence. What is the probable cause?
Your Answer: Damage to the hypogastric plexus during mobilisation of the inferior mesenteric artery
Explanation:The most frequent cause is injury to the autonomic nerves.
During surgical procedures, there is a risk of nerve injury caused by the surgery itself. This is not only important for the patient’s well-being but also from a legal perspective. There are various operations that carry the risk of nerve damage, such as posterior triangle lymph node biopsy, Lloyd Davies stirrups, thyroidectomy, anterior resection of rectum, axillary node clearance, inguinal hernia surgery, varicose vein surgery, posterior approach to the hip, and carotid endarterectomy. Surgeons must have a good understanding of the anatomy of the area they are operating on to minimize the incidence of nerve lesions. Blind placement of haemostats is not recommended as it can also cause nerve damage.
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This question is part of the following fields:
- Gastrointestinal System
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Question 73
Incorrect
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A patient with gastric ulcers has been diagnosed with significantly low levels of somatostatin. The medical consultant suspects that a particular type of cell found in both the pancreas and stomach is affected, leading to the disruption of somatostatin release.
Which type of cell is impacted in this case?Your Answer: S cells
Correct Answer: D cells
Explanation:Somatostatin is released by D cells found in both the pancreas and stomach. These cells release somatostatin to inhibit the hormone gastrin and reduce gastric secretions. The patient’s low levels of somatostatin may have led to an increase in gastrin secretion and stomach acid, potentially causing gastric ulcers. G cells secrete gastrin, while parietal cells secrete gastric acid. Pancreatic cells is too general of a term and does not specify the specific type of cell responsible for somatostatin production.
Overview of Gastrointestinal Hormones
Gastrointestinal hormones play a crucial role in the digestion and absorption of food. These hormones are secreted by various cells in the stomach and small intestine in response to different stimuli such as the presence of food, pH changes, and neural signals.
One of the major hormones involved in food digestion is gastrin, which is secreted by G cells in the antrum of the stomach. Gastrin increases acid secretion by gastric parietal cells, stimulates the secretion of pepsinogen and intrinsic factor, and increases gastric motility. Another hormone, cholecystokinin (CCK), is secreted by I cells in the upper small intestine in response to partially digested proteins and triglycerides. CCK increases the secretion of enzyme-rich fluid from the pancreas, contraction of the gallbladder, and relaxation of the sphincter of Oddi. It also decreases gastric emptying and induces satiety.
Secretin is another hormone secreted by S cells in the upper small intestine in response to acidic chyme and fatty acids. Secretin increases the secretion of bicarbonate-rich fluid from the pancreas and hepatic duct cells, decreases gastric acid secretion, and has a trophic effect on pancreatic acinar cells. Vasoactive intestinal peptide (VIP) is a neural hormone that stimulates secretion by the pancreas and intestines and inhibits acid secretion.
Finally, somatostatin is secreted by D cells in the pancreas and stomach in response to fat, bile salts, and glucose in the intestinal lumen. Somatostatin decreases acid and pepsin secretion, decreases gastrin secretion, decreases pancreatic enzyme secretion, and decreases insulin and glucagon secretion. It also inhibits the trophic effects of gastrin and stimulates gastric mucous production.
In summary, gastrointestinal hormones play a crucial role in regulating the digestive process and maintaining homeostasis in the gastrointestinal tract.
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This question is part of the following fields:
- Gastrointestinal System
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Question 74
Correct
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Which of the following characteristics is atypical for Crohn's disease?
Your Answer: Pseudopolyps on colonoscopy
Explanation:Pseudopolyps manifest in ulcerative colitis as a result of extensive mucosal ulceration. The remaining patches of mucosa can resemble individual polyps.
Understanding Crohn’s Disease
Crohn’s disease is a type of inflammatory bowel disease that can affect any part of the digestive tract, from the mouth to the anus. The exact cause of Crohn’s disease is unknown, but there is a strong genetic component. Inflammation occurs in all layers of the affected area, which can lead to complications such as strictures, fistulas, and adhesions.
Symptoms of Crohn’s disease typically appear in late adolescence or early adulthood and can include non-specific symptoms such as weight loss and lethargy, as well as more specific symptoms like diarrhea, abdominal pain, and perianal disease. Extra-intestinal features, such as arthritis, erythema nodosum, and osteoporosis, are also common in patients with Crohn’s disease.
To diagnose Crohn’s disease, doctors may look for raised inflammatory markers, increased faecal calprotectin, anemia, and low levels of vitamin B12 and vitamin D. It’s important to note that Crohn’s disease shares some features with ulcerative colitis, another type of inflammatory bowel disease, but there are also important differences between the two conditions. Understanding the symptoms and diagnostic criteria for Crohn’s disease can help patients and healthcare providers manage this chronic condition more effectively.
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This question is part of the following fields:
- Gastrointestinal System
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Question 75
Correct
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Which statement about peristalsis is true?
Your Answer: Longitudinal smooth muscle propels the food bolus through the oesophagus
Explanation:Peristalsis: The Movement of Food Through the Digestive System
Peristalsis is the process by which food is moved through the digestive system. Circular smooth muscle contracts behind the food bolus, while longitudinal smooth muscle propels the food through the oesophagus. Primary peristalsis spontaneously moves the food from the oesophagus into the stomach, taking about 9 seconds. Secondary peristalsis occurs when food does not enter the stomach, and stretch receptors are stimulated to cause peristalsis.
In the small intestine, peristalsis waves slow to a few seconds and cause a mixture of chyme. In the colon, three main types of peristaltic activity are recognised. Segmentation contractions are localised contractions in which the bolus is subjected to local forces to maximise mucosal absorption. Antiperistaltic contractions towards the ileum are localised reverse peristaltic waves to slow entry into the colon and maximise absorption. Mass movements are migratory peristaltic waves along the entire colon to empty the organ prior to the next ingestion of a food bolus.
Overall, peristalsis is a crucial process in the digestive system that ensures food is moved efficiently through the body.
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This question is part of the following fields:
- Gastrointestinal System
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Question 76
Correct
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A 35-year-old woman has been diagnosed with gonorrhoeae and prescribed ceftriaxone. She later presents at the emergency department with severe abdominal pain, elevated white blood cell count, and signs of severe colitis. What is the most probable causative organism for these symptoms?
Your Answer: Clostridium difficile
Explanation:The correct answer is C. difficile, as it is the causative organism in pseudomembranous colitis that can occur after recent use of broad-spectrum antibiotics like ceftriaxone. These antibiotics can disrupt the gut flora, allowing C. difficile to thrive. Other antibiotics that can cause C. difficile include PPI, clindamycin, and fluoroquinolones.
Campylobacter, Escherichia coli, and Neisseria gonorrhoeae are incorrect answers. Campylobacter infections are typically caused by undercooked chicken, untreated water, or international travel. E. coli infections are usually caused by contact with infected feces, unwashed foods, or unclean water. Neisseria gonorrhoeae is a sexually transmitted disease that is spread through unprotected sex, not through recent use of broad-spectrum antibiotics. The patient in this case does not have symptoms of gonorrhoeae and there is no indication of unprotected sex after the antibiotic prescription.
Clostridium difficile is a type of bacteria that is commonly found in hospitals. It produces a toxin that can damage the intestines and cause a condition called pseudomembranous colitis. This bacteria usually develops when the normal gut flora is disrupted by broad-spectrum antibiotics, with second and third generation cephalosporins being the leading cause. Other risk factors include the use of proton pump inhibitors. Symptoms of C. difficile infection include diarrhea, abdominal pain, and a raised white blood cell count. The severity of the infection can be determined using the Public Health England severity scale.
To diagnose C. difficile infection, a stool sample is tested for the presence of the C. difficile toxin. Treatment involves reviewing current antibiotic therapy and stopping antibiotics if possible. For a first episode of infection, oral vancomycin is the first-line therapy for 10 days, followed by oral fidaxomicin as second-line therapy and oral vancomycin with or without IV metronidazole as third-line therapy. Recurrent infections may require different treatment options, such as oral fidaxomicin within 12 weeks of symptom resolution or oral vancomycin or fidaxomicin after 12 weeks of symptom resolution. In life-threatening cases, oral vancomycin and IV metronidazole may be used, and surgery may be considered with specialist advice. Other therapies, such as bezlotoxumab and fecal microbiota transplant, may also be considered for preventing recurrences in certain cases.
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This question is part of the following fields:
- Gastrointestinal System
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Question 77
Correct
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As a busy surgical trainee on the colorectal unit, you have been tasked with reviewing the histopathology results for colonic polyps. Which type of polyp described below poses the highest risk of malignant transformation? Please note that this question is specifically for a trainee who is slightly older and more experienced.
Your Answer: Villous adenoma
Explanation:The risk of malignant transformation is highest in villous adenomas, while hyperplastic polyps pose little risk. Hamartomatous polyp syndromes may increase the risk of malignancy in patients, but the polyps themselves have low malignant potential.
Understanding Colonic Polyps and Follow-Up Procedures
Colonic polyps can occur in isolation or as part of polyposis syndromes, with greater than 100 polyps typically present in FAP. The risk of malignancy is related to size, with a 10% risk in a 1 cm adenoma. While isolated adenomas seldom cause symptoms, distally sited villous lesions may produce mucous and electrolyte disturbances if very large.
Follow-up procedures for colonic polyps depend on the number and size of the polyps. Low-risk cases with 1 or 2 adenomas less than 1 cm require no follow-up or re-colonoscopy for 5 years. Moderate-risk cases with 3 or 4 small adenomas or 1 adenoma greater than 1 cm require a re-scope at 3 years. High-risk cases with more than 5 small adenomas or more than 3 with 1 of them greater than 1 cm require a re-scope at 1 year.
Segmental resection or complete colectomy may be necessary in cases of incomplete excision of malignant polyps, malignant sessile polyps, malignant pedunculated polyps with submucosal invasion, polyps with poorly differentiated carcinoma, or familial polyposis coli. Screening from teenager up to 40 years by 2 yearly sigmoidoscopy/colonoscopy is recommended. Rectal polypoidal lesions may be treated with trans anal endoscopic microsurgery.
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This question is part of the following fields:
- Gastrointestinal System
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Question 78
Correct
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A 67-year-old man comes to the emergency department complaining of abrupt abdominal pain. He reports the pain as cramping, with a severity of 6/10, and spread throughout his abdomen. The patient has a medical history of hypertension and type 2 diabetes mellitus. He used to smoke and has a smoking history of 40 pack years.
What is the most probable part of the colon affected in this patient?Your Answer: Splenic flexure
Explanation:Ischaemic colitis frequently affects the splenic flexure, which is a vulnerable area due to its location at the border of regions supplied by different arteries. Symptoms such as cramping and generalised abdominal pain, along with a history of smoking and hypertension, suggest a diagnosis of ischaemic colitis. While the rectosigmoid junction is also a watershed area, it is less commonly affected than the splenic flexure. Other regions of the large bowel are less susceptible to ischaemic colitis.
Understanding Ischaemic Colitis
Ischaemic colitis is a condition that occurs when there is a temporary reduction in blood flow to the large bowel. This can cause inflammation, ulcers, and bleeding. The condition is more likely to occur in areas of the bowel that are located at the borders of the territory supplied by the superior and inferior mesenteric arteries, such as the splenic flexure.
When investigating ischaemic colitis, doctors may look for a sign called thumbprinting on an abdominal x-ray. This occurs due to mucosal edema and hemorrhage. It is important to diagnose and treat ischaemic colitis promptly to prevent complications and ensure a full recovery.
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This question is part of the following fields:
- Gastrointestinal System
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Question 79
Incorrect
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Sophie, a 5-year-old girl, visits her doctor with her mother, complaining of a lump in her groin that appears and disappears. The lump is easily reducible.
The doctor suspects an indirect inguinal hernia, although it is difficult to differentiate between femoral, direct inguinal, and indirect inguinal hernias in such a young patient.
Sophie's mother is curious about the cause of her daughter's hernia. What is the pathology of an indirect inguinal hernia?Your Answer: Protrusion through a weakness of abdominal wall musculature
Correct Answer: Protrusion through the failure of the processus vaginalis to regress
Explanation:Indirect inguinal hernias are caused by the failure of the processus vaginalis to regress, resulting in a protrusion through the deep inguinal ring and into the inguinal canal. In males, it may progress into the scrotum, while in females, it may enter the labia. This type of hernia is located lateral to the epigastric vessels.
On the other hand, direct inguinal hernias are usually caused by weakening in the abdominal musculature, which occurs with age. The protrusion enters the inguinal canal through the posterior wall, which is medial to the epigastric vessels. It may exit through the superficial inguinal ring.
The tunica vaginalis is a layer that surrounds the testes and contains a small amount of serous fluid, reducing friction between the scrotum and the testes. Meanwhile, the tunica albuginea is a layer of connective tissue that covers the ovaries, testicles, and corpora cavernosa of the penis.
Understanding Inguinal Hernias
Inguinal hernias are the most common type of abdominal wall hernias, with 75% of cases falling under this category. They are more prevalent in men, with a 25% lifetime risk of developing one. The main symptom is a lump in the groin area, which disappears when pressure is applied or when the patient lies down. Discomfort and aching are also common, especially during physical activity. However, severe pain is rare, and strangulation is even rarer.
The traditional classification of inguinal hernias into indirect and direct types is no longer relevant in clinical management. Instead, the current consensus is to treat medically fit patients, even if they are asymptomatic. A hernia truss may be an option for those who are not fit for surgery, but it has limited use in other patients. Mesh repair is the preferred method, as it has the lowest recurrence rate. Unilateral hernias are usually repaired through an open approach, while bilateral and recurrent hernias are repaired laparoscopically.
After surgery, patients are advised to return to non-manual work after 2-3 weeks for open repair and 1-2 weeks for laparoscopic repair. Complications may include early bruising and wound infection, as well as late chronic pain and recurrence. It is important to seek medical attention if any of these symptoms occur.
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This question is part of the following fields:
- Gastrointestinal System
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Question 80
Correct
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Which one of the following triggers the production of stomach acid?
Your Answer: Histamine
Explanation:Gastrin is produced by G cells and stimulates the production of gastric acid. Pepsin is responsible for digesting protein and is secreted simultaneously with gastrin. Secretin, produced by mucosal cells in the duodenum and jejunum, inhibits gastric acid production and stimulates the production of bile and pancreatic juice. Gastric inhibitory peptide, produced in response to fatty acids, inhibits the release of gastrin and acid secretion from parietal cells. Cholecystokinin, also produced by mucosal cells in the duodenum and jejunum in response to fatty acids, inhibits acid secretion from parietal cells and causes the gallbladder to contract while relaxing the sphincter of Oddi.
Overview of Gastrointestinal Hormones
Gastrointestinal hormones play a crucial role in the digestion and absorption of food. These hormones are secreted by various cells in the stomach and small intestine in response to different stimuli such as the presence of food, pH changes, and neural signals.
One of the major hormones involved in food digestion is gastrin, which is secreted by G cells in the antrum of the stomach. Gastrin increases acid secretion by gastric parietal cells, stimulates the secretion of pepsinogen and intrinsic factor, and increases gastric motility. Another hormone, cholecystokinin (CCK), is secreted by I cells in the upper small intestine in response to partially digested proteins and triglycerides. CCK increases the secretion of enzyme-rich fluid from the pancreas, contraction of the gallbladder, and relaxation of the sphincter of Oddi. It also decreases gastric emptying and induces satiety.
Secretin is another hormone secreted by S cells in the upper small intestine in response to acidic chyme and fatty acids. Secretin increases the secretion of bicarbonate-rich fluid from the pancreas and hepatic duct cells, decreases gastric acid secretion, and has a trophic effect on pancreatic acinar cells. Vasoactive intestinal peptide (VIP) is a neural hormone that stimulates secretion by the pancreas and intestines and inhibits acid secretion.
Finally, somatostatin is secreted by D cells in the pancreas and stomach in response to fat, bile salts, and glucose in the intestinal lumen. Somatostatin decreases acid and pepsin secretion, decreases gastrin secretion, decreases pancreatic enzyme secretion, and decreases insulin and glucagon secretion. It also inhibits the trophic effects of gastrin and stimulates gastric mucous production.
In summary, gastrointestinal hormones play a crucial role in regulating the digestive process and maintaining homeostasis in the gastrointestinal tract.
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This question is part of the following fields:
- Gastrointestinal System
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Question 81
Correct
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Throughout the process of embryonic development, what is the accurate source of the pancreas?
Your Answer: Ventral and dorsal endodermal outgrowths of the duodenum
Explanation:The pancreas originates from two outgrowths of the duodenum – one from the ventral side and the other from the dorsal side. The ventral outgrowth is located near or together with the hepatic diverticulum, while the larger dorsal outgrowth emerges slightly above the ventral one and extends into the mesoduodenum and mesogastrium. After the two buds merge, the duct of the ventral outgrowth becomes the primary pancreatic duct.
Anatomy of the Pancreas
The pancreas is located behind the stomach and is a retroperitoneal organ. It can be accessed surgically by dividing the peritoneal reflection that connects the greater omentum to the transverse colon. The pancreatic head is situated in the curvature of the duodenum, while its tail is close to the hilum of the spleen. The pancreas has various relations with other organs, such as the inferior vena cava, common bile duct, renal veins, superior mesenteric vein and artery, crus of diaphragm, psoas muscle, adrenal gland, kidney, aorta, pylorus, gastroduodenal artery, and splenic hilum.
The arterial supply of the pancreas is through the pancreaticoduodenal artery for the head and the splenic artery for the rest of the organ. The venous drainage for the head is through the superior mesenteric vein, while the body and tail are drained by the splenic vein. The ampulla of Vater is an important landmark that marks the transition from foregut to midgut and is located halfway along the second part of the duodenum. Overall, understanding the anatomy of the pancreas is crucial for surgical procedures and diagnosing pancreatic diseases.
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This question is part of the following fields:
- Gastrointestinal System
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Question 82
Correct
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A 42-year-old female patient arrives at the emergency department complaining of intense abdominal pain on the right side. Upon further inquiry, she describes the pain as crampy, intermittent, and spreading to her right shoulder. She has no fever. The patient notes that the pain worsens after meals.
Which hormone is accountable for the fluctuation in pain?Your Answer: Cholecystokinin
Explanation:The hormone that increases gallbladder contraction is Cholecystokinin (CCK). It is secreted by I cells in the upper small intestine, particularly in response to a high-fat meal. Although it has many functions, its role in increasing gallbladder contraction may exacerbate biliary colic caused by gallstones in the patient described.
Gastrin, insulin, and secretin are also hormones that can be released in response to food intake, but they do not have any known effect on gallbladder contraction. Therefore, CCK is the most appropriate answer.
Overview of Gastrointestinal Hormones
Gastrointestinal hormones play a crucial role in the digestion and absorption of food. These hormones are secreted by various cells in the stomach and small intestine in response to different stimuli such as the presence of food, pH changes, and neural signals.
One of the major hormones involved in food digestion is gastrin, which is secreted by G cells in the antrum of the stomach. Gastrin increases acid secretion by gastric parietal cells, stimulates the secretion of pepsinogen and intrinsic factor, and increases gastric motility. Another hormone, cholecystokinin (CCK), is secreted by I cells in the upper small intestine in response to partially digested proteins and triglycerides. CCK increases the secretion of enzyme-rich fluid from the pancreas, contraction of the gallbladder, and relaxation of the sphincter of Oddi. It also decreases gastric emptying and induces satiety.
Secretin is another hormone secreted by S cells in the upper small intestine in response to acidic chyme and fatty acids. Secretin increases the secretion of bicarbonate-rich fluid from the pancreas and hepatic duct cells, decreases gastric acid secretion, and has a trophic effect on pancreatic acinar cells. Vasoactive intestinal peptide (VIP) is a neural hormone that stimulates secretion by the pancreas and intestines and inhibits acid secretion.
Finally, somatostatin is secreted by D cells in the pancreas and stomach in response to fat, bile salts, and glucose in the intestinal lumen. Somatostatin decreases acid and pepsin secretion, decreases gastrin secretion, decreases pancreatic enzyme secretion, and decreases insulin and glucagon secretion. It also inhibits the trophic effects of gastrin and stimulates gastric mucous production.
In summary, gastrointestinal hormones play a crucial role in regulating the digestive process and maintaining homeostasis in the gastrointestinal tract.
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This question is part of the following fields:
- Gastrointestinal System
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Question 83
Correct
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A 25-year-old male patient visits the surgical clinic with an inguinal hernia. During the examination, a small direct hernia is observed along with pigmented spots on his palms, soles, and around his mouth. The patient had undergone a reduction of an intussusception when he was 10 years old. If a colonoscopy is performed, which of the following lesions is most likely to be detected?
Your Answer: Hamartomas
Explanation:It is probable that he has Peutz-Jeghers syndrome, a condition that is linked to the presence of Hamartomas.
Understanding Peutz-Jeghers Syndrome
Peutz-Jeghers syndrome is a genetic condition that is inherited in an autosomal dominant manner. It is characterized by the presence of numerous hamartomatous polyps in the gastrointestinal tract, particularly in the small bowel. In addition, patients with this syndrome may also have pigmented freckles on their lips, face, palms, and soles.
While the polyps themselves are not cancerous, individuals with Peutz-Jeghers syndrome have an increased risk of developing other types of gastrointestinal tract cancers. In fact, around 50% of patients will have died from another gastrointestinal tract cancer by the age of 60 years.
Common symptoms of Peutz-Jeghers syndrome include small bowel obstruction, which is often due to intussusception, as well as gastrointestinal bleeding. Management of this condition is typically conservative unless complications develop. It is important for individuals with Peutz-Jeghers syndrome to undergo regular screening and surveillance to detect any potential cancerous growths early on.
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This question is part of the following fields:
- Gastrointestinal System
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Question 84
Incorrect
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A 16-year-old boy presents to the hospital with suspected appendicitis. Upon examination, he exhibits maximum tenderness at McBurney's point. Can you identify the location of McBurney's point?
Your Answer: 2/3rds laterally along the line between the umbilicus and the midpoint of the inguinal canal
Correct Answer: 2/3rds laterally along the line between the umbilicus and the anterior superior iliac spine
Explanation:To locate McBurney’s point, one should draw an imaginary line from the umbilicus to the anterior superior iliac spine on the right-hand side and then find the point that is 2/3rds of the way along this line. The other choices do not provide the correct location for this anatomical landmark.
Acute appendicitis is a common condition that requires surgery and can occur at any age, but is most prevalent in young people aged 10-20 years. The pathogenesis of acute appendicitis involves lymphoid hyperplasia or a faecolith, which leads to obstruction of the appendiceal lumen. This obstruction causes gut organisms to invade the appendix wall, resulting in oedema, ischaemia, and possibly perforation.
The most common symptom of acute appendicitis is abdominal pain, which is typically peri-umbilical and radiates to the right iliac fossa due to localised peritoneal inflammation. Other symptoms include mild pyrexia, anorexia, and nausea. Examination may reveal generalised or localised peritonism, rebound and percussion tenderness, guarding and rigidity, and classical signs such as Rovsing’s sign and psoas sign.
Diagnosis of acute appendicitis is typically based on raised inflammatory markers and compatible history and examination findings. Imaging may be used in certain cases, such as ultrasound in females where pelvic organ pathology is suspected. Management of acute appendicitis involves appendicectomy, which can be performed via an open or laparoscopic approach. Patients with perforated appendicitis require copious abdominal lavage, while those without peritonitis who have an appendix mass should receive broad-spectrum antibiotics and consideration given to performing an interval appendicectomy. Intravenous antibiotics alone have been trialled as a treatment for appendicitis, but evidence suggests that this is associated with a longer hospital stay and up to 20% of patients go on to have an appendicectomy within 12 months.
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This question is part of the following fields:
- Gastrointestinal System
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Question 85
Correct
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A 50-year-old man with persistent constipation visits his doctor seeking a laxative prescription. Despite having a good appetite and hydration, he has no notable medical history except for constipation. He is a non-alcoholic but occasionally smokes when socializing with friends.
The doctor intends to prescribe a laxative to alleviate the patient's constipation, but like any other medication, laxatives have side effects that must be taken into account before prescribing.
What is the laxative that has been demonstrated to have carcinogenic properties?Your Answer: Co-danthramer
Explanation:Co-danthramer is a genotoxic laxative that should only be prescribed to patients receiving palliative care due to its potential to cause cancer. Other laxatives should be considered first for patients with constipation. However, if constipation is not improved by other laxatives, co-danthramer may be prescribed to palliative patients. It is important to note that a high-fibre diet, adequate fluid intake, and exercise are recommended for all patients with constipation. Fruits and vegetables high in fibre and sorbitol, as well as fruit juices high in sorbitol, can also be helpful in preventing and treating constipation.
Understanding Laxatives
Laxatives are frequently prescribed medications in clinical practice, with constipation being a common issue among patients. While constipation may be a symptom of underlying pathology, many patients experience simple idiopathic constipation. The British National Formulary (BNF) categorizes laxatives into four groups: osmotic, stimulant, bulk-forming, and faecal softeners.
Osmotic laxatives, such as lactulose, macrogols, and rectal phosphates, work by drawing water into the bowel to soften stools and promote bowel movements. Stimulant laxatives, including senna, docusate, bisacodyl, and glycerol, stimulate the muscles in the bowel to contract and move stool along. Co-danthramer, a combination of a stimulant and a bulk-forming laxative, should only be prescribed to palliative patients due to its potential carcinogenic effects.
Bulk-forming laxatives, such as ispaghula husk and methylcellulose, work by increasing the bulk of stool and promoting regular bowel movements. Faecal softeners, such as arachis oil enemas, are not commonly prescribed but can be used to soften stool and ease bowel movements.
In summary, understanding the different types of laxatives and their mechanisms of action can help healthcare professionals prescribe the most appropriate treatment for patients experiencing constipation.
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This question is part of the following fields:
- Gastrointestinal System
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Question 86
Correct
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A 75-year-old male with a history of atrial fibrillation and diverticulitis presents to the emergency department with severe abdominal pain. After thorough investigation, including mesenteric angiography, it was found that the left colic flexure was experiencing ischemia. Which artery provides direct supply to this region through its branches?
Your Answer: Inferior mesenteric artery (IMA)
Explanation:The inferior mesenteric artery supplies the distal 1/3 of the transverse colon, while the proximal two thirds are supplied by the middle colic artery, a branch of the SMA. The left colic artery, a branch of the IMA, supplies the remaining distal portion. Although the left colic artery is the primary supplier, collateral flow from branches of the middle colic artery also contributes. The left colic flexure, located between the end of the SMA and the start of the IMA’s blood supply, is a watershed region that can be susceptible to ischemia due to atherosclerotic changes or hypotension.
The splenic artery directly supplies the spleen and also has branches that supply the stomach and pancreas. There is no such thing as the AMA or PMA.
The Transverse Colon: Anatomy and Relations
The transverse colon is a part of the large intestine that begins at the hepatic flexure, where the right colon makes a sharp turn. At this point, it becomes intraperitoneal and is connected to the inferior border of the pancreas by the transverse mesocolon. The middle colic artery and vein are contained within the mesentery. The greater omentum is attached to the superior aspect of the transverse colon, which can be easily separated. The colon undergoes another sharp turn at the splenic flexure, where the greater omentum remains attached up to this point. The distal 1/3 of the transverse colon is supplied by the inferior mesenteric artery.
The transverse colon is related to various structures. Superiorly, it is in contact with the liver, gallbladder, the greater curvature of the stomach, and the lower end of the spleen. Inferiorly, it is related to the small intestine. Anteriorly, it is in contact with the greater omentum, while posteriorly, it is in contact with the descending portion of the duodenum, the head of the pancreas, convolutions of the jejunum and ileum, and the spleen. Understanding the anatomy and relations of the transverse colon is important for medical professionals in diagnosing and treating various gastrointestinal conditions.
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This question is part of the following fields:
- Gastrointestinal System
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Question 87
Correct
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A 36-year-old female patient presents with persistent dyspepsia of 6 months duration. She failed multiple trials of conservative treatment by her GP, therefore, she was referred for the gastroenterologist for further review.
Investigations were done and her urea breath test was negative for Helicobacter pylori. Gastroscopy revealed multiple gastroduodenal ulcers. What type of cells are affected by the high levels of fasting gastrin detected?Your Answer: Gastric parietal cells
Explanation:The secretion of gastrin hormone from G cells in the antrum of the stomach is responsible for increasing the secretion of H+ by gastric parietal cells. Additionally, chief cells secrete pepsin, which is a proteolytic enzyme, while D cells in the pancreas and stomach secrete somatostatin hormone. Gastrin hormone is released in response to distension of the stomach and vagal stimulation.
Overview of Gastrointestinal Hormones
Gastrointestinal hormones play a crucial role in the digestion and absorption of food. These hormones are secreted by various cells in the stomach and small intestine in response to different stimuli such as the presence of food, pH changes, and neural signals.
One of the major hormones involved in food digestion is gastrin, which is secreted by G cells in the antrum of the stomach. Gastrin increases acid secretion by gastric parietal cells, stimulates the secretion of pepsinogen and intrinsic factor, and increases gastric motility. Another hormone, cholecystokinin (CCK), is secreted by I cells in the upper small intestine in response to partially digested proteins and triglycerides. CCK increases the secretion of enzyme-rich fluid from the pancreas, contraction of the gallbladder, and relaxation of the sphincter of Oddi. It also decreases gastric emptying and induces satiety.
Secretin is another hormone secreted by S cells in the upper small intestine in response to acidic chyme and fatty acids. Secretin increases the secretion of bicarbonate-rich fluid from the pancreas and hepatic duct cells, decreases gastric acid secretion, and has a trophic effect on pancreatic acinar cells. Vasoactive intestinal peptide (VIP) is a neural hormone that stimulates secretion by the pancreas and intestines and inhibits acid secretion.
Finally, somatostatin is secreted by D cells in the pancreas and stomach in response to fat, bile salts, and glucose in the intestinal lumen. Somatostatin decreases acid and pepsin secretion, decreases gastrin secretion, decreases pancreatic enzyme secretion, and decreases insulin and glucagon secretion. It also inhibits the trophic effects of gastrin and stimulates gastric mucous production.
In summary, gastrointestinal hormones play a crucial role in regulating the digestive process and maintaining homeostasis in the gastrointestinal tract.
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This question is part of the following fields:
- Gastrointestinal System
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Question 88
Correct
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Which of the following is not an extraintestinal manifestation of Crohn's disease?
Your Answer: Erythema multiforme
Explanation:Understanding Crohn’s Disease
Crohn’s disease is a type of inflammatory bowel disease that can affect any part of the digestive tract, from the mouth to the anus. The exact cause of Crohn’s disease is unknown, but there is a strong genetic component. Inflammation occurs in all layers of the affected area, which can lead to complications such as strictures, fistulas, and adhesions.
Symptoms of Crohn’s disease typically appear in late adolescence or early adulthood and can include non-specific symptoms such as weight loss and lethargy, as well as more specific symptoms like diarrhea, abdominal pain, and perianal disease. Extra-intestinal features, such as arthritis, erythema nodosum, and osteoporosis, are also common in patients with Crohn’s disease.
To diagnose Crohn’s disease, doctors may look for raised inflammatory markers, increased faecal calprotectin, anemia, and low levels of vitamin B12 and vitamin D. It’s important to note that Crohn’s disease shares some features with ulcerative colitis, another type of inflammatory bowel disease, but there are also important differences between the two conditions. Understanding the symptoms and diagnostic criteria for Crohn’s disease can help patients and healthcare providers manage this chronic condition more effectively.
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This question is part of the following fields:
- Gastrointestinal System
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Question 89
Correct
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A 28-year-old woman presents to her GP with a complaint of diarrhoea lasting for 5 months. She reports the presence of blood in her stool and feeling excessively fatigued.
During abdominal examination, tenderness is noted in the lower left quadrant.
The patient is referred for a colonoscopy and biopsy.
What characteristic would you anticipate finding based on the probable diagnosis?Your Answer: Inflammation from rectum extending proximally
Explanation:Ulcerative colitis is a form of inflammatory bowel disease that usually manifests with symptoms like fatigue, left lower quadrant pain, and bloody diarrhoea. The inflammation associated with ulcerative colitis starts at the rectum and extends proximally, but it does not spread beyond the ileocaecal valve.
Unlike Crohn’s disease, ulcerative colitis does not typically present with a cobblestone appearance during colonoscopy.
While diverticula can cause rectal bleeding and abdominal pain, they are more common in older patients and would not be expected in a patient of this age.
In Crohn’s disease, skip lesions are present, whereas in ulcerative colitis, the inflammation is continuous.
Inflammatory bowel disease (IBD) is a condition that includes two main types: Crohn’s disease and ulcerative colitis. Although they share many similarities in terms of symptoms, diagnosis, and treatment, there are some key differences between the two. Crohn’s disease is characterized by non-bloody diarrhea, weight loss, upper gastrointestinal symptoms, mouth ulcers, perianal disease, and a palpable abdominal mass in the right iliac fossa. On the other hand, ulcerative colitis is characterized by bloody diarrhea, abdominal pain in the left lower quadrant, tenesmus, gallstones, and primary sclerosing cholangitis. Complications of Crohn’s disease include obstruction, fistula, and colorectal cancer, while ulcerative colitis has a higher risk of colorectal cancer than Crohn’s disease. Pathologically, Crohn’s disease lesions can be seen anywhere from the mouth to anus, while ulcerative colitis inflammation always starts at the rectum and never spreads beyond the ileocaecal valve. Endoscopy and radiology can help diagnose and differentiate between the two types of IBD.
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This question is part of the following fields:
- Gastrointestinal System
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Question 90
Incorrect
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A 52-year-old woman visits her primary care physician after her spouse noticed a gradual yellowing of her eyes over the past three days. The patient reports experiencing fatigue and excessive sleepiness for several years, along with occasional bouts of intense itching. She has no significant medical history. Lab tests reveal elevated levels of alkaline phosphatase, IgM antibodies, and anti-mitochondrial antibodies. What is the underlying pathology of this patient's condition?
Your Answer: Bile duct inflammation associated with areas of narrowing and sclerosis
Correct Answer: Interlobular bile duct granulomatous destruction with dense lymphocytic infiltrate
Explanation:The patient’s symptoms and laboratory findings suggest a cholestatic disease, specifically primary biliary cholangitis, which is an autoimmune condition of the biliary tract. This disease is more common in middle-aged women and can present with symptoms such as fatigue and pruritus. Non-alcoholic steatohepatitis is a metabolic syndrome-related condition characterized by triglyceride accumulation and myofibroblast proliferation, while primary sclerosing cholangitis is characterized by bile duct inflammation and sclerosis. Alcoholic hepatitis is caused by long-term alcohol misuse and is characterized by macrovesicular fatty change, spotty necrosis, and fibrosis.
Primary biliary cholangitis is a chronic liver disorder that affects middle-aged women. It is thought to be an autoimmune condition that damages interlobular bile ducts, causing progressive cholestasis and potentially leading to cirrhosis. The classic presentation is itching in a middle-aged woman. It is associated with Sjogren’s syndrome, rheumatoid arthritis, systemic sclerosis, and thyroid disease. Diagnosis involves immunology and imaging tests. Management includes ursodeoxycholic acid, cholestyramine for pruritus, and liver transplantation in severe cases. Complications include cirrhosis, osteomalacia and osteoporosis, and an increased risk of hepatocellular carcinoma.
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This question is part of the following fields:
- Gastrointestinal System
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Question 91
Incorrect
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A 72-year-old woman visits her doctor complaining of painful legs, particularly in her thighs, which occur after walking and subside on rest. She occasionally takes paracetamol to alleviate the pain. Her medical history includes hyperlipidaemia, type II diabetes mellitus, hypertension, and depression. The physician suspects that her pain may be due to claudication of the femoral artery, which is a continuation of the external iliac artery. Can you correctly identify the anatomical landmark where the external iliac artery becomes the femoral artery?
Your Answer: Femoral vein
Correct Answer: Inguinal ligament
Explanation:After passing the inguinal ligament, the external iliac artery transforms into the femoral artery. This means that the other options provided are not accurate. Here is a brief explanation of their anatomical importance:
– The medial edge of the sartorius muscle creates the lateral wall of the femoral triangle.
– The medial edge of the adductor longus muscle creates the medial wall of the femoral triangle.
– The femoral vein creates the lateral border of the femoral canal.
– The pectineus muscle creates the posterior border of the femoral canal.The inguinal canal is located above the inguinal ligament and measures 4 cm in length. Its superficial ring is situated in front of the pubic tubercle, while the deep ring is found about 1.5-2 cm above the halfway point between the anterior superior iliac spine and the pubic tubercle. The canal is bounded by the external oblique aponeurosis, inguinal ligament, lacunar ligament, internal oblique, transversus abdominis, external ring, and conjoint tendon. In males, the canal contains the spermatic cord and ilioinguinal nerve, while in females, it houses the round ligament of the uterus and ilioinguinal nerve.
The boundaries of Hesselbach’s triangle, which are frequently tested, are located in the inguinal region. Additionally, the inguinal canal is closely related to the vessels of the lower limb, which should be taken into account when repairing hernial defects in this area.
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This question is part of the following fields:
- Gastrointestinal System
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Question 92
Correct
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A 67-year-old female is hospitalized with acute pancreatitis. What factor would indicate a poor prognosis?
Your Answer: Glucose 15.8mmol/l
Explanation:The Glasgow Prognostic Score is a useful tool for assessing the severity of acute pancreatitis. If three or more of the following criteria are present within the first 48 hours, it is likely that the patient is experiencing severe pancreatitis and should be referred to the High Dependency Unit or Intensive Care Unit. Conversely, if the score is less than three, severe pancreatitis is unlikely. The criteria include: age over 55 years, white blood cell count over 15 x 109/L, urea over 16 mmol/L, glucose over 10 mmol/L, pO2 less than 8 kPa (60 mm Hg), albumin less than 32 g/L, calcium less than 2 mmol/L, LDH over 600 units/L, and AST/ALT over 200 units. Based on these criteria, the only option that meets the threshold for severe pancreatitis is a glucose level of 15.8 mmol/L.
Acute pancreatitis is a condition that is primarily caused by gallstones and alcohol consumption in the UK. However, there are other factors that can contribute to the development of this condition. A popular mnemonic used to remember these factors is GET SMASHED, which stands for gallstones, ethanol, trauma, steroids, mumps, autoimmune diseases, scorpion venom, hypertriglyceridaemia, hyperchylomicronaemia, hypercalcaemia, hypothermia, ERCP, and certain drugs. It is important to note that pancreatitis is seven times more common in patients taking mesalazine than sulfasalazine. CT scans can show diffuse parenchymal enlargement with oedema and indistinct margins in patients with acute pancreatitis.
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This question is part of the following fields:
- Gastrointestinal System
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Question 93
Incorrect
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You are working on a general surgical receiving ward when a 70-year-old woman is admitted from the emergency department with sudden and severe abdominal pain that radiates to her back. The patient reports that she is normally healthy, but has been struggling with rheumatoid arthritis for the past few years, which is improving with treatment. She does not consume alcohol and has had an open cholecystectomy in the past, although she cannot recall when it occurred.
Blood tests were conducted in the emergency department:
- Hb 140 g/L (Male: 135-180, Female: 115-160)
- Platelets 350 * 109/L (150-400)
- WBC 12.9 * 109/L (4.0-11.0)
- Amylase 1200 U/L (70-300)
Based on the likely diagnosis, what is the most probable cause of this patient's presentation?Your Answer: Sodium valproate
Correct Answer: Azathioprine
Explanation:Acute pancreatitis can be caused by azathioprine.
It is important to note that the symptoms and blood tests suggest acute pancreatitis. The most common causes of this condition are gallstones and alcohol, but these have been ruled out through patient history. Although there is a possibility of retained stones in the common bile duct after cholecystectomy, it is unlikely given the time since the operation.
Other less common causes include trauma (which is not present in this case) and sodium valproate (which the patient has not been taking).
Therefore, the most likely cause of acute pancreatitis in this case is azathioprine, an immunosuppressive medication used to treat rheumatoid arthritis, which is known to have a side effect of acute pancreatitis.
Acute pancreatitis is a condition that is primarily caused by gallstones and alcohol consumption in the UK. However, there are other factors that can contribute to the development of this condition. A popular mnemonic used to remember these factors is GET SMASHED, which stands for gallstones, ethanol, trauma, steroids, mumps, autoimmune diseases, scorpion venom, hypertriglyceridaemia, hyperchylomicronaemia, hypercalcaemia, hypothermia, ERCP, and certain drugs. It is important to note that pancreatitis is seven times more common in patients taking mesalazine than sulfasalazine. CT scans can show diffuse parenchymal enlargement with oedema and indistinct margins in patients with acute pancreatitis.
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This question is part of the following fields:
- Gastrointestinal System
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Question 94
Incorrect
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A 63-year-old man is undergoing a left hemicolectomy for carcinoma of the descending colon. During mobilisation of the left colon, the registrar notices blood in the left paracolic gutter. What is the most likely source of bleeding in this scenario?
Your Answer: Left renal vein
Correct Answer: Spleen
Explanation:Traction injuries during colonic surgery often result in spleen tears, while bleeding from other structures would not be visible in the paracolic gutter before incision of the paracolonic peritoneal edge.
Anatomy of the Left Colon
The left colon is a part of the large intestine that passes inferiorly and becomes extraperitoneal in its posterior aspect. It is closely related to the ureter and gonadal vessels, which may be affected by disease processes. At a certain level, the left colon becomes the sigmoid colon, which is wholly intraperitoneal once again. The sigmoid colon is highly mobile and may even be found on the right side of the abdomen. As it passes towards the midline, the taenia blend marks the transition between the sigmoid colon and upper rectum.
The blood supply of the left colon comes from the inferior mesenteric artery. However, the marginal artery, which comes from the right colon, also contributes significantly. This contribution becomes clinically significant when the inferior mesenteric artery is divided surgically, such as during an abdominal aortic aneurysm repair. Understanding the anatomy of the left colon is important for diagnosing and treating diseases that affect this part of the large intestine.
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This question is part of the following fields:
- Gastrointestinal System
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Question 95
Correct
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A 23-year-old man presents to his GP with complaints of persistent diarrhoea, abdominal pain, and weight loss. He reports experiencing generalised pain and feeling extremely fatigued. The patient denies any blood in his stool and has a past medical history of type 1 diabetes mellitus.
Upon investigation, the patient's tissue transglutaminase IgA (tTG-IgA) levels are found to be elevated. What is the most probable finding on duodenal biopsy for this likely diagnosis?Your Answer: Villous atrophy
Explanation:Malabsorption occurs in coeliac disease due to villous atrophy, which is caused by an immune response to gluten in the gastrointestinal tract. This can lead to nutritional deficiencies in affected individuals. While coeliac disease is associated with a slightly increased risk of small bowel carcinoma, it is unlikely to occur in a young patient. Crypt hyperplasia, not hypoplasia, is a common finding in coeliac disease. Coeliac disease is associated with a decreased number of goblet cells, not an increased number. Non-caseating granulomas are typically seen in Crohn’s disease, not coeliac disease.
Understanding Coeliac Disease
Coeliac disease is an autoimmune disorder that affects approximately 1% of the UK population. It is caused by sensitivity to gluten, a protein found in wheat, barley, and rye. Repeated exposure to gluten leads to villous atrophy, which causes malabsorption. Coeliac disease is associated with various conditions, including dermatitis herpetiformis and autoimmune disorders such as type 1 diabetes mellitus and autoimmune hepatitis. It is strongly linked to HLA-DQ2 and HLA-DQ8.
To diagnose coeliac disease, NICE recommends screening patients who exhibit signs and symptoms such as chronic or intermittent diarrhea, failure to thrive or faltering growth in children, persistent or unexplained gastrointestinal symptoms, prolonged fatigue, recurrent abdominal pain, sudden or unexpected weight loss, unexplained anemia, autoimmune thyroid disease, dermatitis herpetiformis, irritable bowel syndrome, type 1 diabetes, and first-degree relatives with coeliac disease.
Complications of coeliac disease include anemia, hyposplenism, osteoporosis, osteomalacia, lactose intolerance, enteropathy-associated T-cell lymphoma of the small intestine, subfertility, and unfavorable pregnancy outcomes. In rare cases, it can lead to esophageal cancer and other malignancies.
The diagnosis of coeliac disease is confirmed through a duodenal biopsy, which shows complete atrophy of the villi with flat mucosa and marked crypt hyperplasia, intraepithelial lymphocytosis, and dense mixed inflammatory infiltrate in the lamina propria. Treatment involves a lifelong gluten-free diet.
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This question is part of the following fields:
- Gastrointestinal System
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Question 96
Correct
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A 35-year-old woman came in with a 7-month history of upper abdominal pain and nausea. She reported no weight loss. An upper GI endoscopy showed mild gastritis, but her symptoms persisted even after a 3-month course of proton pump inhibitors. A CT scan was done and revealed a probable gastrinoma. Which type of cell does the hormone produced by this tumor target to stimulate acid secretion?
Your Answer: Parietal cell
Explanation:The secretion of H+ by gastric parietal cells is increased by gastrin.
Overview of Gastrointestinal Hormones
Gastrointestinal hormones play a crucial role in the digestion and absorption of food. These hormones are secreted by various cells in the stomach and small intestine in response to different stimuli such as the presence of food, pH changes, and neural signals.
One of the major hormones involved in food digestion is gastrin, which is secreted by G cells in the antrum of the stomach. Gastrin increases acid secretion by gastric parietal cells, stimulates the secretion of pepsinogen and intrinsic factor, and increases gastric motility. Another hormone, cholecystokinin (CCK), is secreted by I cells in the upper small intestine in response to partially digested proteins and triglycerides. CCK increases the secretion of enzyme-rich fluid from the pancreas, contraction of the gallbladder, and relaxation of the sphincter of Oddi. It also decreases gastric emptying and induces satiety.
Secretin is another hormone secreted by S cells in the upper small intestine in response to acidic chyme and fatty acids. Secretin increases the secretion of bicarbonate-rich fluid from the pancreas and hepatic duct cells, decreases gastric acid secretion, and has a trophic effect on pancreatic acinar cells. Vasoactive intestinal peptide (VIP) is a neural hormone that stimulates secretion by the pancreas and intestines and inhibits acid secretion.
Finally, somatostatin is secreted by D cells in the pancreas and stomach in response to fat, bile salts, and glucose in the intestinal lumen. Somatostatin decreases acid and pepsin secretion, decreases gastrin secretion, decreases pancreatic enzyme secretion, and decreases insulin and glucagon secretion. It also inhibits the trophic effects of gastrin and stimulates gastric mucous production.
In summary, gastrointestinal hormones play a crucial role in regulating the digestive process and maintaining homeostasis in the gastrointestinal tract.
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This question is part of the following fields:
- Gastrointestinal System
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Question 97
Correct
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A 63-year-old man with a history of alcohol abuse presents with recurrent epigastric pain. An OGD reveals the presence of varices in the lower esophagus. To prevent variceal bleeding, which medication would be the most suitable prophylactic option?
Your Answer: Propranolol
Explanation:A non-cardioselective β blocker (NSBB) is the appropriate medication for prophylaxis against oesophageal bleeding in patients with varices. NSBBs work by causing splanchnic vasoconstriction, which reduces portal blood flow. Omeprazole, warfarin, and unfractionated heparin are not suitable options for this purpose.
Variceal haemorrhage is a serious condition that requires prompt and effective management. The initial treatment involves resuscitation of the patient, correction of clotting abnormalities, and administration of vasoactive agents such as terlipressin or octreotide. Prophylactic IV antibiotics are also recommended to reduce mortality in patients with liver cirrhosis. Endoscopic variceal band ligation is the preferred method for controlling bleeding, and the use of a Sengstaken-Blakemore tube or Transjugular Intrahepatic Portosystemic Shunt (TIPSS) may be necessary if bleeding cannot be controlled. However, TIPSS can lead to exacerbation of hepatic encephalopathy, which is a common complication.
To prevent variceal haemorrhage, prophylactic measures such as propranolol and endoscopic variceal band ligation (EVL) are recommended. Propranolol has been shown to reduce rebleeding and mortality compared to placebo. EVL is superior to endoscopic sclerotherapy and should be performed at two-weekly intervals until all varices have been eradicated. Proton pump inhibitor cover is given to prevent EVL-induced ulceration. NICE guidelines recommend offering endoscopic variceal band ligation for the primary prevention of bleeding for people with cirrhosis who have medium to large oesophageal varices.
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This question is part of the following fields:
- Gastrointestinal System
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Question 98
Correct
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The action of which one of the following brush border enzymes leads to the production of glucose and galactose?
Your Answer: Lactase
Explanation:Enzymes play a crucial role in the breakdown of carbohydrates in the gastrointestinal system. Amylase, which is present in both saliva and pancreatic secretions, is responsible for breaking down starch into sugar. On the other hand, brush border enzymes such as maltase, sucrase, and lactase are involved in the breakdown of specific disaccharides. Maltase cleaves maltose into glucose and glucose, sucrase cleaves sucrose into fructose and glucose, while lactase cleaves lactose into glucose and galactose. These enzymes work together to ensure that carbohydrates are broken down into their simplest form for absorption into the bloodstream.
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This question is part of the following fields:
- Gastrointestinal System
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Question 99
Incorrect
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An elderly man, aged 72, visits his family doctor with complaints of a vague abdominal pain that has been bothering him for the past few months. He is unable to pinpoint the exact location of the pain but mentions that it is more severe around the epigastric region. The pain worsens after meals and has resulted in a loss of appetite and recent weight loss. The man denies experiencing any nausea or vomiting and reports only mild constipation. He has a long-standing history of type 2 diabetes mellitus, hypertension, and dyslipidemia and is currently taking glipizide, insulin injections, atorvastatin, candesartan, and metoprolol as regular medications. Additionally, he is a current smoker with a 25 pack-year history. On examination, the abdomen is soft and non-tender. The man’s vital signs include a heart rate of 62 beats per minute, respiratory rate of 13 breaths per minute, and blood pressure of 147/91 mmHg. What is the most likely mechanism responsible for this patient’s symptoms?
Your Answer: Low-fibre diet and decreased intestinal motility due to ageing
Correct Answer: Fatty accumulation, foam cell formation and fibrous plaque formation in the wall of blood vessels
Explanation:The patient’s symptoms suggest that he may have chronic mesenteric ischemia, which is often caused by atherosclerosis in the arteries supplying the splanchnic circulatory vessels. There is no indication of recent abdominal surgery or an underlying inflammatory process. Constipation is a common issue in elderly individuals, but it is not typically associated with abdominal pain. Meckel diverticulum is a congenital defect that can cause symptoms such as melaena, acute appendicitis, and acute abdominal pain due to ectopic acid secretion. Diverticulitis is characterized by inflammation in the colon, often due to a lack of dietary fiber. Small bowel obstruction due to adhesions is a surgical emergency. Chronic mesenteric ischemia, also known as intestinal angina, is common in individuals with atherosclerotic diseases such as diabetics, smokers, hypertensive patients, and those with dyslipidemia. As the population ages and chronic diseases become more prevalent, the incidence and prevalence of chronic mesenteric ischemia are expected to increase.
Ischaemia to the lower gastrointestinal tract can result in acute mesenteric ischaemia, chronic mesenteric ischaemia, and ischaemic colitis. Common predisposing factors include increasing age, atrial fibrillation, other causes of emboli, cardiovascular disease risk factors, and cocaine use. Common features include abdominal pain, rectal bleeding, diarrhea, fever, and elevated white blood cell count with lactic acidosis. CT is the investigation of choice. Acute mesenteric ischaemia is typically caused by an embolism and requires urgent surgery. Chronic mesenteric ischaemia presents with intermittent abdominal pain. Ischaemic colitis is an acute but transient compromise in blood flow to the large bowel and may require surgery in a minority of cases.
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This question is part of the following fields:
- Gastrointestinal System
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Question 100
Correct
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A 42-year-old female presents to the emergency department with severe generalised abdominal pain and haematemesis. The patient reports ongoing epigastric pain over the past few months which was worse after eating meals. She had a similar but milder episode about 4 years ago, which was treated with omeprazole. Past medical history includes osteoarthritis for which she takes ibuprofen.
Clinical observations reveal a heart rate of 120 beats per minute, blood pressure of 90/78 mmHg, respiratory rate of 25/min, oxygen saturations of 98% on air and a temperature of 37.5ºC. On examination, the patient has severe epigastric tenderness on palpation.
What is the first-line treatment for the likely diagnosis?Your Answer: Endoscopic intervention
Explanation:The most likely diagnosis for the patient is a perforated peptic ulcer, which may have been caused by their use of ibuprofen. The recommended first-line treatment according to NICE guidelines is endoscopic intervention, which can confirm the diagnosis and stop the bleeding. This involves injecting adrenaline into the bleeding site and using cautery and/or clip application. Helicobacter pylori eradication therapy is not appropriate in this case, as the patient’s symptoms suggest a perforated peptic ulcer rather than peptic ulcer disease caused by H. pylori. IV proton-pump inhibitor infusion may be considered later, but the patient requires immediate management with endoscopic intervention.
Managing Acute Bleeding in Peptic Ulcer Disease
Peptic ulcer disease is a condition that can lead to acute bleeding, which is the most common complication of the disease. In fact, bleeding accounts for about three-quarters of all problems associated with peptic ulcer disease. The gastroduodenal artery is often the source of significant gastrointestinal bleeding in patients with this condition. The most common symptom of acute bleeding in peptic ulcer disease is haematemesis, but patients may also experience melaena, hypotension, and tachycardia.
When managing acute bleeding in peptic ulcer disease, an ABC approach should be taken, as with any upper gastrointestinal haemorrhage. Intravenous proton pump inhibitors are the first-line treatment, and endoscopic intervention is typically the preferred approach. However, if endoscopic intervention fails (which occurs in approximately 10% of patients), urgent interventional angiography with transarterial embolization or surgery may be necessary. By following these management strategies, healthcare providers can effectively address acute bleeding in patients with peptic ulcer disease.
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This question is part of the following fields:
- Gastrointestinal System
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