-
Question 1
Correct
-
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.
-
This question is part of the following fields:
- Gastrointestinal System
-
-
Question 2
Correct
-
Which one of the following structures is located most posteriorly at the porta hepatis?
Your Answer: Portal vein
Explanation:At the porta hepatis, the most posterior structure is the portal vein, while the common bile duct is created by the merging of the common hepatic duct and the cystic duct. The common hepatic duct extends and becomes the common bile duct.
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.
-
This question is part of the following fields:
- Gastrointestinal System
-
-
Question 3
Incorrect
-
A 50-year-old man with chronic abdominal pain and a known alcohol dependency visits his gastroenterologist with a recent onset of diarrhoea. The gastroenterologist plans to conduct an abdominal MRI to assess the functionality of the responsible organ. Before the MRI, a hormone is administered.
What is the purpose of this hormone?Your Answer: Decreased pancreatic secretion of endogenous hormones
Correct Answer: Increased pancreatic secretion of bicarbonate
Explanation:The patient in question is likely suffering from chronic pancreatitis due to excessive alcohol consumption. This can lead to poor exocrine pancreatic function and result in diarrhea due to insufficient production of digestive enzymes. To assess pancreatic exocrine function, the patient is undergoing testing with secretin, a hormone that stimulates the secretion of bicarbonate-rich fluid from pancreas and hepatic duct cells, as seen on abdominal MRI.
Somatostatin, on the other hand, is a hormone that decreases the secretion of endogenous hormones from the pancreas and also reduces the exogenous production of bicarbonate. Therefore, it is not useful in testing pancreatic function.
Somatostatin also inhibits the secretion of hydrochloric acid from gastric parietal cells and is released from delta cells in the stomach when the pH is low.
Increased intestinal secretion of bicarbonate is not the primary mechanism for neutralizing gastric acid. It is only supplementary to the pancreatic release of bicarbonate and is stimulated by gastric contents in the duodenum, not by secretin.
There is no specific hormone that increases pancreatic secretion of insulin and glucagon, but somatostatin can decrease the secretion of both hormones.
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.
-
This question is part of the following fields:
- Gastrointestinal System
-
-
Question 4
Correct
-
A 45-year-old female with known type 1 diabetes and Graves' disease presents to the GP with worsening fatigue. She describes a history of headaches, shortness of breath and palpitations. Blood tests are taken and the results are displayed below.
Haemoglobin 79 g/dl
MCV 103 fl
White cell count 4.2 mmol/l
Platelets 220 mmol/l
What is the most likely vitamin or mineral deficiency in this patient?Your Answer: B12
Explanation:Anaemia is characterized by classic symptoms such as headaches, shortness of breath, and palpitations. The primary nutritional factors that can cause anaemia are deficiencies in B12, Folate, and Iron.
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.
-
This question is part of the following fields:
- Gastrointestinal System
-
-
Question 5
Correct
-
A 15-year-old boy, with a family history of Gilbert's syndrome, is showing symptoms of hepatic dysfunction. Upon conducting liver function tests, it is found that he has elevated levels of unconjugated bilirubin. After genetic testing, it is confirmed that he has Gilbert's syndrome. What is the reason behind the increased levels of unconjugated bilirubin in Gilbert's syndrome?
Your Answer: Reduced levels of UDP-glucuronosyl transferase-1
Explanation:Gilbert’s syndrome is characterized by a decrease in UDP glucuronosyltransferase levels.
Enhanced drug effects can occur due to reduced warfarin metabolism caused by CYP2C9 deficiency.
Elevated GGT levels are often caused by pancreatic disease, cholestasis, excessive alcohol consumption, and certain medications.
Dubin-Johnson syndrome is associated with defective hepatocyte excretion of conjugated bilirubin.
Disordered metabolism of clopidogrel and other drugs, including proton-pump inhibitors, anticonvulsants, and sedatives, can result from reduced CYP2C19 levels.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.
-
This question is part of the following fields:
- Gastrointestinal System
-
-
Question 6
Incorrect
-
A 36-year-old man is brought to the Emergency Department in an ambulance after being found unconscious by a friend. Shortly after arriving at the hospital, he becomes tachycardic, hypotensive, and stops breathing. The medical team suspects shock and examines him. What could be a potential cause of obstructive shock resulting from interference in ventricular filling?
Your Answer: Myocardial infarction
Correct Answer: Tension pneumothorax
Explanation:Shock can be caused by various factors, but only tension pneumothorax affects ventricular filling. Distributive shock, such as anaphylactic shock, hypovolaemic shock caused by chemical burns, and cardiogenic shock resulting from myocardial infarction are other examples. Obstructive shock caused by pulmonary embolism interferes with ventricular emptying, not filling.
Shock is a condition where there is not enough blood flow to the tissues. There are five main types of shock: septic, haemorrhagic, neurogenic, cardiogenic, and anaphylactic. Septic shock is caused by an infection that triggers a particular response in the body. Haemorrhagic shock is caused by blood loss, and there are four classes of haemorrhagic shock based on the amount of blood loss and associated symptoms. Neurogenic shock occurs when there is a disruption in the autonomic nervous system, leading to decreased vascular resistance and decreased cardiac output. Cardiogenic shock is caused by heart disease or direct myocardial trauma. Anaphylactic shock is a severe, life-threatening allergic reaction. Adrenaline is the most important drug in treating anaphylaxis and should be given as soon as possible.
-
This question is part of the following fields:
- Gastrointestinal System
-
-
Question 7
Incorrect
-
A somatostatinoma patient with constantly elevated somatostatin levels experiences a significant decrease in the secretion of many endocrine hormones. Which hormone responsible for stimulating the pancreas and hepatic duct cells to secrete bicarbonate-rich fluid is affected when S cells are not stimulated?
Your Answer: Vasoactive intestinal peptide
Correct Answer: Secretin
Explanation:Secretin is the correct answer as it is produced by S cells in the upper small intestine and stimulates the pancreas and hepatic duct cells to secrete bicarbonate-rich fluid. It also reduces gastric acid secretion and promotes the growth of pancreatic acinar cells. However, if there is a somatostatinoma present, there will be an excess of somatostatin which inhibits the production of secretin by S cells.
Cholecystokinin (CCK) is an incorrect answer as it is released by I-cells in the upper small intestine in response to fats and proteins. CCK stimulates the gallbladder and pancreas to contract and secrete bile enzymes into the duodenum.
Gastrin is an incorrect answer as it is produced by G cells in the stomach and stimulates the release of hydrochloric acid into the stomach.
Ghrelin is an incorrect answer as it is released to stimulate hunger, particularly before meals.
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.
-
This question is part of the following fields:
- Gastrointestinal System
-
-
Question 8
Incorrect
-
A 30-year-old male presents to the emergency department after vomiting blood. He had been out drinking heavily with friends and had vomited multiple times, with the last episode containing a significant amount of blood.
Upon examination, the patient appeared intoxicated and had a pulse of 96 bpm and a blood pressure of 120/74 mmHg. Abdominal examination revealed no abnormalities.
What is the probable diagnosis?Your Answer: Gastric ulceration
Correct Answer: Mallory-Weiss tear
Explanation:Mallory Weiss Tear and Alcoholic Gastritis
Repeated episodes of vomiting due to alcohol consumption can lead to a Mallory Weiss tear, which is a mucosal tear in the esophagus. This tear can cause hematemesis, which is vomiting of blood. This is a common occurrence in habitual drinkers who suffer from alcoholic gastritis. Along with upper abdominal pain, this condition can cause a rise in esophageal pressures, leading to mucosal tears. However, most patients only lose small amounts of blood, and symptoms can often be resolved with minimal intervention. It is important to seek medical attention if symptoms persist or worsen.
-
This question is part of the following fields:
- Gastrointestinal System
-
-
Question 9
Incorrect
-
As a GP, you are evaluating a 35-year-old female patient who has been experiencing a persistent burning sensation in her epigastrium that is temporarily relieved by eating meals. Your initial suspicion of H. pylori infection was ruled out by a negative serology test, and a two-week trial of full-dose proton pump inhibitor and triple eradication therapy failed to alleviate her symptoms. An endoscopy revealed multiple duodenal ulcers, and upon further questioning, the patient disclosed that her mother has a pituitary tumor. Which hormone is most likely to be elevated in this patient?
Your Answer: Somatostatin
Correct Answer: Gastrin
Explanation:Zollinger-Ellison Syndrome and Gastrinoma
Zollinger-Ellison syndrome is a familial condition that predisposes individuals to benign or malignant tumors of the pituitary and pancreas with parathyroid hyperplasia causing hyperparathyroidism. This autosomal dominant inherited syndrome should be considered in patients who present with unusual endocrine tumors, especially if they are relatively young at diagnosis or have a relevant family history.
One manifestation of Zollinger-Ellison syndrome is the development of a pancreatic tumor called a gastrinoma, which secretes the hormone gastrin. Gastrin stimulates the release of hydrochloric acid from parietal cells in the stomach, which optimizes conditions for protein digesting enzymes. However, excessive production of gastrin can occur in gastrinomas, leading to excessive HCL production that can denature the mucosa and submosa of the gastrointestinal tract, causing symptoms, ulceration, and even perforation of the duodenum.
While other pancreatic tumors can also produce hormones such as insulin or glucagon, the symptoms and clinical findings in this case suggest a diagnosis of gastrinoma. Cholecystokinin and somatostatin are hormones that have inhibitory effects on HCL secretion and do not fit with the clinical picture. Cholecystokinin also produces the feeling of satiety.
-
This question is part of the following fields:
- Gastrointestinal System
-
-
Question 10
Incorrect
-
A 35-year-old woman arrives at the Emergency Department with a sudden onset of painless left-sided facial weakness, along with difficulty speaking and a drooping mouth. She expresses concern about having a stroke, but her medical history is unremarkable. Upon further examination, you rule out a stroke and suspect that she may be experiencing Bell's palsy, an unexplained paralysis of the facial nerve.
What signs would you anticipate discovering during the examination?Your Answer: Normal corneal reflex
Correct Answer: Taste impairment of the anterior tongue
Explanation:The facial nerve’s chorda tympani branch is responsible for providing taste sensation to the anterior two-thirds of the tongue. Bell’s palsy is a condition characterized by unilateral facial nerve weakness or paralysis, which can result in impaired taste sensation in the anterior tongue.
Upper motor neuron lesions typically spare the forehead, as alternative nerve routes can still provide innervation. In contrast, lower motor neuron lesions like Bell’s palsy can cause forehead paralysis.
While ptosis may occur in Bell’s palsy, it typically presents unilaterally rather than bilaterally.
Although patients with Bell’s palsy may complain of tearing eyes, tear production is actually decreased due to loss of control of the eyelids and facial muscles.
The facial nerve controls the motor aspect of the corneal reflex, so an abnormal corneal reflex may be observed in Bell’s palsy.
Nerve Supply of the Tongue
The tongue is a complex organ that plays a crucial role in speech and taste. It is innervated by three different cranial nerves, each responsible for different functions. The anterior two-thirds of the tongue receive general sensation from the lingual branch of the mandibular division of the trigeminal nerve (CN V3) and taste sensation from the chorda tympani branch of the facial nerve (CN VII). On the other hand, the posterior one-third of the tongue receives both general sensation and taste sensation from the glossopharyngeal nerve (CN IX).
In terms of motor function, the hypoglossal nerve (CN XII) is responsible for controlling the movements of the tongue. It is important to note that the tongue’s nerve supply is essential for proper functioning, and any damage to these nerves can result in speech and taste disorders.
-
This question is part of the following fields:
- Gastrointestinal System
-
-
Question 11
Correct
-
A 32-year-old alcoholic woman presents with visible jaundice and confusion and is admitted to the gastroenterology ward. Upon examination, she has a distended tender abdomen with hepatomegaly and shifting dullness. All her observations are within normal limits. The following blood test results are obtained:
- Hb: 121 g/L (normal range for females: 115-160 g/L)
- MCV: 103 g/L (normal range: 82-100 g/L)
- Bilirubin: 78 µmol/L (normal range: 3-17 µmol/L)
- ALP: 112 u/L (normal range: 30-100 u/L)
- ALT: 276 u/L (normal range: 3-40 u/L)
- AST: 552 u/L (normal range: 3-30 u/L)
- γGT: 161 u/L (normal range: 8-60 u/L)
An aspirate of fluid is taken and shows a serum-ascites albumin gradient (SAAG) of 14 g/L. What is the most likely diagnosis that explains the SAAG value in this patient?Your Answer: Portal hypertension
Explanation:Ascites can be diagnosed by measuring the SAAG value, with a high SAAG gradient (>11g/L) indicating the presence of portal hypertension. In the case of a SAAG value of >11g/L, the ascites is considered a transudate and is likely caused by portal hypertension. This is consistent with the patient’s symptoms, which suggest ascites due to alcoholic liver disease leading to liver cirrhosis and portal hypertension. Other potential causes of ascites would result in an exudative picture with a SAAG value of <11g/L. Biliary ascites is a rare consequence of biliary procedures or trauma, and would present with abdominal distension but not hepatomegaly. While bile is sterile, peritonitis is likely to occur, leading to septic symptoms. However, the SAAG value and the patient’s symptoms make biliary ascites less likely. Bowel obstruction is not consistent with the patient’s symptoms, as it would not explain the presence of jaundice. While a distended abdomen may be present, other features of delirium would also be expected. Additionally, a patient with bowel obstruction would report a history of not passing flatus or bowel movements. Nephrotic syndrome would present with oedema, proteinuria, and hypoalbuminaemia, which are not described in the patient’s symptoms. The raised liver enzymes and macrocytic anaemia are more consistent with liver pathology. Ascites is a medical condition characterized by the accumulation of abnormal amounts of fluid in the abdominal cavity. The causes of ascites can be classified into two groups based on the serum-ascites albumin gradient (SAAG) level. If the SAAG level is greater than 11g/L, it indicates portal hypertension, which is commonly caused by liver disorders such as cirrhosis, alcoholic liver disease, and liver metastases. Other causes of portal hypertension include cardiac conditions like right heart failure and constrictive pericarditis, as well as infections like tuberculous peritonitis. On the other hand, if the SAAG level is less than 11g/L, ascites may be caused by hypoalbuminaemia, malignancy, pancreatitis, bowel obstruction, and other conditions. The management of ascites involves reducing dietary sodium and sometimes fluid restriction if the sodium level is less than 125 mmol/L. Aldosterone antagonists like spironolactone are often prescribed, and loop diuretics may be added if necessary. Therapeutic abdominal paracentesis may be performed for tense ascites, and large-volume paracentesis requires albumin cover to reduce the risk of complications. Prophylactic antibiotics may also be given to prevent spontaneous bacterial peritonitis. In some cases, a transjugular intrahepatic portosystemic shunt (TIPS) may be considered.
-
This question is part of the following fields:
- Gastrointestinal System
-
-
Question 12
Incorrect
-
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: S cells
Correct 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.
-
This question is part of the following fields:
- Gastrointestinal System
-
-
Question 13
Incorrect
-
A 73-year-old man is undergoing an open abdominal aortic aneurysm repair. The aneurysm is located in a juxtarenal location and surgical access to the neck of aneurysm is difficult. Which one of the following structures may be divided to improve access?
Your Answer: Cisterna chyli
Correct Answer: Left renal vein
Explanation:During juxtarenal aortic surgery, the neck of the aneurysm can cause stretching of the left renal vein, which may lead to its division. This can worsen the nephrotoxic effects of the surgery, especially when a suprarenal clamp is also used. However, intentionally dividing the Cisterna Chyli will not enhance access and can result in chyle leakage. Similarly, dividing the transverse colon is not beneficial and can increase the risk of graft infection. Lastly, dividing the SMA is unnecessary for a juxtarenal procedure.
The abdominal aorta is a major blood vessel that originates from the 12th thoracic vertebrae and terminates at the fourth lumbar vertebrae. It is located in the abdomen and is surrounded by various organs and structures. The posterior relations of the abdominal aorta include the vertebral bodies of the first to fourth lumbar vertebrae. The anterior relations include the lesser omentum, liver, left renal vein, inferior mesenteric vein, third part of the duodenum, pancreas, parietal peritoneum, and peritoneal cavity. The right lateral relations include the right crus of the diaphragm, cisterna chyli, azygos vein, and inferior vena cava (which becomes posterior distally). The left lateral relations include the fourth part of the duodenum, duodenal-jejunal flexure, and left sympathetic trunk. Overall, the abdominal aorta is an important blood vessel that supplies oxygenated blood to various organs in the abdomen.
-
This question is part of the following fields:
- Gastrointestinal System
-
-
Question 14
Correct
-
A 50-year-old man has metastatic adenocarcinoma of the colon that has spread throughout his body. Which of the following tumor markers is expected to be elevated?
Your Answer: Carcinoembryonic antigen
Explanation:Using CEA as a screening tool for colonic cancer is not justifiable. While it is true that CEA levels are elevated in colonic cancer, this is also the case in non-malignant conditions such as cirrhosis and colitis. Additionally, the highest levels of CEA are typically seen in cases of metastatic disease. Therefore, CEA should not be used to monitor colitis patients for the development of colonic cancer. This information is supported by a study published in the BMJ in 2009.
Diagnosis and Staging of Colorectal Cancer
Diagnosis of colorectal cancer is typically done through a colonoscopy, which is considered the gold standard as long as it is complete and provides good mucosal visualization. Other options for diagnosis include double-contrast barium enema and CT colonography. Once a malignant diagnosis is made, patients will undergo staging using chest, abdomen, and pelvic CT scans. Patients with rectal cancer will also undergo evaluation of the mesorectum with pelvic MRI scanning. For examination purposes, the Dukes and TNM systems are preferred.
Tumour Markers in Colorectal Cancer
Carcinoembryonic antigen (CEA) is the main tumour marker in colorectal cancer. While not all tumours secrete CEA, it is still used as a marker for disease burden and is once again being used routinely in follow-up. However, it is important to note that CEA levels may also be raised in conditions such as IBD.
-
This question is part of the following fields:
- Gastrointestinal System
-
-
Question 15
Correct
-
What is the anatomical distribution of ulcerative colitis?
Your Answer: Starts at rectum + rarely spreads beyond ileocaecal valve + continuous
Explanation: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.
-
This question is part of the following fields:
- Gastrointestinal System
-
-
Question 16
Correct
-
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.
-
This question is part of the following fields:
- Gastrointestinal System
-
-
Question 17
Incorrect
-
A 72-year-old man comes to the clinic with a left groin swelling and reports experiencing moderate pain and discomfort. The diagnosis is an inguinal hernia, and he is scheduled for elective surgery to repair the defect. During the procedure, which nerve running through the inguinal canal is at risk of being damaged?
Your Answer: Obturator nerve
Correct Answer: Ilioinguinal nerve
Explanation:The inguinal canal is a crucial anatomical structure that houses the spermatic cord in males and the ilioinguinal nerve in both genders. The ilioinguinal and iliohypogastric nerves stem from the L1 nerve root and run through the canal. The ilioinguinal nerve enters the canal via the abdominal muscles and exits through the external inguinal ring. It is primarily a sensory nerve that provides sensation to the upper medial thigh. If the nerve is damaged during hernia repair, patients may experience numbness in this area after surgery.
Other nerves that pass through the pelvis include the femoral nerve, which descends behind the inguinal canal, the obturator nerve, which travels through the obturator foramen, and the sciatic nerve, which exits the pelvis through the greater sciatic foramen and runs posteriorly.
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.
-
This question is part of the following fields:
- Gastrointestinal System
-
-
Question 18
Incorrect
-
A 25-year-old woman presents to the gastrointestinal clinic with a history of abdominal bloating, diarrhoea, and fatigue for the past 6 months. She experiences severe cramps after most meals and struggles to focus on her work at the office.
After conducting investigations, it is found that her tissue transglutaminases (TTG) are positive. What is a potential complication of the suspected underlying diagnosis?Your Answer: Sclerosing cholangitis
Correct Answer: Hyposplenism
Explanation:Hyposplenism is a possible complication of coeliac disease. The patient’s symptoms and positive tissue transglutaminases support the diagnosis of coeliac disease, which can lead to malabsorption of important nutrients like iron, folate, and vitamin B12. Hyposplenism may occur due to autoimmune processes and loss of lymphocyte recirculation caused by inflammation in the colon. However, hepatomegaly, pancreatitis, and polycythaemia are not associated with 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.
-
This question is part of the following fields:
- Gastrointestinal System
-
-
Question 19
Correct
-
A 25-year-old male patient visits his general practitioner complaining of abdominal pain, diarrhea, and painful aphthous ulcers that have been bothering him for the last four weeks. He has also observed that his clothes have become loose lately.
What is the typical disease pattern associated with his condition?Your Answer: Inflammation anywhere from the mouth to anus
Explanation:Crohn’s disease is characterized by inflammation that can occur anywhere from the mouth to the anus. This patient’s symptoms, including weight loss, abdominal pain, and diarrhea, suggest inflammatory bowel disease (IBD). The presence of mouth ulcers indicates Crohn’s disease, as it is known for causing discontinuous inflammation throughout the gastrointestinal tract. Ulcerative colitis, on the other hand, does not cause mouth ulcers and typically involves continuous inflammation that extends from the rectum. While colorectal polyposis can be a complication of IBD, it alone does not explain the patient’s symptoms. Ulcerative colitis is characterized by continuous inflammation that is limited to the submucosa and originates in the rectum, which is not the case for this patient.
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.
-
This question is part of the following fields:
- Gastrointestinal System
-
-
Question 20
Incorrect
-
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: Salbutamol use
Correct 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.
-
This question is part of the following fields:
- Gastrointestinal System
-
-
Question 21
Correct
-
A young woman with Crohn's disease has been experiencing severe exacerbations of her condition over the past year, despite standard medication. You have decided to prescribe Infliximab, a biologic drug.
What tests should be ordered before prescribing this medication?Your Answer: Interferon-gamma release assay
Explanation:Before prescribing any biologic medication, it is important to check the patient’s tuberculosis status by performing an interferon-gamma release assay. This test is used to detect TB latency and prevent reactivation of TB as a complication of biologic therapy. Other tests such as alpha-fetoprotein, spirometry, and brain-natriuretic peptide are not necessary before starting biologic treatment.
Biological Agents and Their Uses
Biological agents are substances that are used to target specific molecules or receptors in the body to treat various diseases. Adalimumab, infliximab, and etanercept are biological agents that inhibit TNF alpha, a molecule that plays a role in inflammation. These agents are used to treat Crohn’s disease and rheumatoid disease. Bevacizumab is an anti-VEGF agent that targets the growth of blood vessels in tumors. It is used to treat colorectal cancer, renal cancer, and glioblastoma. Trastuzumab is a biological agent that targets the HER receptor and is used to treat breast cancer. Imatinib is a tyrosine kinase inhibitor that is used to treat gastrointestinal stromal tumors and chronic myeloid leukemia. Basiliximab targets the IL2 binding site and is used in renal transplants. Cetuximab is an epidermal growth factor inhibitor that is used to treat EGF positive colorectal cancers. Biological agents have revolutionized the treatment of many diseases and continue to be an important area of research and development in medicine.
-
This question is part of the following fields:
- Gastrointestinal System
-
-
Question 22
Incorrect
-
A 32-year-old woman is being evaluated for an abdominal mass. She delivered her first child vaginally and without any issues. Biopsy results indicate the presence of differentiated fibroblasts in sheets, which is indicative of a desmoid tumor. What is a potential risk factor for this type of tumor?
Your Answer: RET oncogene
Correct Answer: APC mutations
Explanation:Desmoid tumours are more likely to occur in individuals with APC mutations.
Pancreatic and hepatic cancer have been linked to CA-199.
Breast cancer is strongly linked to BRCA1 and BRCA2 mutations.
Burkitt’s lymphoma, a high-grade B-cell neoplasm, is associated with translocation of the C-myc gene.
Desmoid tumours are growths that arise from musculoaponeurotic structures and are made up of clonal proliferations of myofibroblasts. They are typically firm and have a tendency to infiltrate surrounding tissue. These tumours are often seen in patients with familial adenomatous polyposis coli, and are most commonly found in women after childbirth in the rectus abdominis muscle. Bi allelic APC mutations are usually present in desmoid tumours.
The preferred treatment for desmoid tumours is radical surgical resection, although radiotherapy and chemotherapy may be considered in some cases. Non-surgical therapy is generally less effective than surgical resection. In certain cases of abdominal desmoids, observation may be preferred as some tumours may spontaneously regress. However, desmoids have a high likelihood of local recurrence. These tumours consist of sheets of differentiated fibroblasts.
-
This question is part of the following fields:
- Gastrointestinal System
-
-
Question 23
Incorrect
-
During a ward round on the gastroenterology ward, you assess a 75-year-old man with a history of hepatocellular carcinoma. He spent most of his life in Pakistan, where he consumed a diet high in grains and chicken. He has never contracted a hepatitis virus. Despite being a non-smoker, he has resided in a household where other inhabitants smoke indoors for the majority of his adult life.
What is the potential risk factor for hepatocellular carcinoma that this patient may have been exposed to?Your Answer: Family history of hepatocellular carcinoma
Correct Answer: Aflatoxin
Explanation:Hepatocellular carcinoma is commonly caused by chronic hepatitis B infection worldwide and chronic hepatitis C infection in Europe. However, there are other significant risk factors to consider, such as aflatoxins. These toxic carcinogens are produced by certain types of mold and can be found in improperly stored grains and seeds. While Caroli’s disease and primary sclerosing cholangitis are risk factors for cholangiocarcinoma, they are less significant for hepatocellular carcinoma.
Hepatocellular carcinoma (HCC) is a type of cancer that ranks third in terms of prevalence worldwide. The most common cause of HCC globally is chronic hepatitis B, while chronic hepatitis C is the leading cause in Europe. The primary risk factor for developing HCC is liver cirrhosis, which can result from various factors such as hepatitis B & C, alcohol, haemochromatosis, and primary biliary cirrhosis. Other risk factors include alpha-1 antitrypsin deficiency, hereditary tyrosinosis, glycogen storage disease, aflatoxin, certain drugs, porphyria cutanea tarda, male sex, diabetes mellitus, and metabolic syndrome.
HCC often presents late and may exhibit features of liver cirrhosis or failure such as jaundice, ascites, RUQ pain, hepatomegaly, pruritus, and splenomegaly. In some cases, it may manifest as decompensation in patients with chronic liver disease. Elevated levels of alpha-fetoprotein (AFP) are also common. High-risk groups such as patients with liver cirrhosis secondary to hepatitis B & C or haemochromatosis, and men with liver cirrhosis secondary to alcohol should undergo screening with ultrasound (+/- AFP).
Management options for early-stage HCC include surgical resection, liver transplantation, radiofrequency ablation, transarterial chemoembolisation, and sorafenib, a multikinase inhibitor. Proper management and early detection are crucial in improving the prognosis of HCC.
-
This question is part of the following fields:
- Gastrointestinal System
-
-
Question 24
Correct
-
A 42-year-old man is found to have a right-sided colon cancer and a significant family history of colorectal and ovarian cancer. Upon genetic testing, he is diagnosed with hereditary non-polyposis colorectal cancer (HNPCC) caused by a mutation in the MSH2 gene. What is the role of this gene?
Your Answer: DNA mismatch repair
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.
-
This question is part of the following fields:
- Gastrointestinal System
-
-
Question 25
Incorrect
-
A 42-year-old woman experiences repeated episodes of biliary colic. How much bile enters the duodenum in a day, approximately?
Your Answer: 100 mL
Correct Answer: 500 mL
Explanation:The small bowel receives a daily supply of bile ranging from 500 mL to 1.5 L, with the majority of bile salts being reused through the enterohepatic circulation. The contraction of the gallbladder results in a lumenal pressure of around 25 cm water, which can cause severe pain in cases of biliary colic.
Bile is a liquid that is produced in the liver at a rate of 500ml to 1500mL per day. It is made up of bile salts, bicarbonate, cholesterol, steroids, and water. The flow of bile is regulated by three factors: hepatic secretion, gallbladder contraction, and sphincter of oddi resistance. Bile salts are absorbed in the terminal ileum and are recycled up to six times a day, with over 90% of all bile salts being recycled.
There are two types of bile salts: primary and secondary. Primary bile salts include cholate and chenodeoxycholate, while secondary bile salts are formed by bacterial action on primary bile salts and include deoxycholate and lithocholate. Deoxycholate is reabsorbed, while lithocholate is insoluble and excreted.
Gallstones can form when there is an excess of cholesterol in the bile. Bile salts have a detergent action and form micelles, which have a lipid center that transports fats. However, excessive amounts of cholesterol cannot be transported in this way and will precipitate, resulting in the formation of cholesterol-rich gallstones.
-
This question is part of the following fields:
- Gastrointestinal System
-
-
Question 26
Correct
-
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: 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.
-
This question is part of the following fields:
- Gastrointestinal System
-
-
Question 27
Incorrect
-
A 27-year-old man presents with fatigue and joint pains for the past 8 months. He cannot recall any specific trigger for the symptoms and they have been persistent. During examination, you observe that his skin is quite tanned but no other significant findings are noted.
The following are his blood test results:
- Bilirubin: 10 umol/L
- ALT: 120 IU/L
- Albumin: 35 g/L
- Ferritin: 450 mg/mL
- Transferrin saturation: 70%
- Random plasma glucose: 17.0 mmol/L
Afterwards, a genetic test was conducted and returned with positive results. Based on the most probable diagnosis, what is the mode of inheritance for this disease?Your Answer: Autosomal dominant
Correct Answer: Autosomal recessive
Explanation:The probable condition affecting the patient is hereditary haemochromatosis, which is inherited in an autosomal recessive manner. The presence of iron overload and abnormal liver function tests are indicative of this diagnosis. Additionally, the patient’s elevated blood glucose levels and skin pigmentation changes may suggest the presence of bronze diabetes.
Understanding Haemochromatosis: Symptoms and Complications
Haemochromatosis is a genetic disorder that affects iron absorption and metabolism, leading to iron accumulation in the body. It is caused by mutations in the HFE gene on both copies of chromosome 6. This disorder is prevalent in people of European descent, with 1 in 10 carrying a mutation in the genes affecting iron metabolism. Early symptoms of haemochromatosis are often non-specific, such as lethargy and arthralgia, and may go unnoticed. However, as the disease progresses, patients may experience fatigue, erectile dysfunction, and skin pigmentation.
Other complications of haemochromatosis include diabetes mellitus, liver disease, cardiac failure, hypogonadism, and arthritis. While some symptoms are reversible with treatment, such as cardiomyopathy, skin pigmentation, diabetes mellitus, hypogonadotrophic hypogonadism, and arthropathy, liver cirrhosis is irreversible.
-
This question is part of the following fields:
- Gastrointestinal System
-
-
Question 28
Incorrect
-
A 15-year-old girl comes to the clinic with her father. She has lost 10kg in the last 2 months. Recently, her father found her vomiting in the bathroom. The girl admits to struggling with her self-esteem and body image, and has been inducing vomiting after meals. She feels anxious in social situations. During the examination, you observe swelling above the angle of the mandible, indicating parotid gland enlargement. Which nerve supplies the parasympathetic fibers to the parotid gland?
Your Answer: Greater auricular nerve
Correct Answer: Glossopharyngeal nerve
Explanation:The correct answer is the glossopharyngeal nerve, which is the ninth cranial nerve. It provides parasympathetic innervation to the parotid gland and carries taste and sensation from the posterior third of the tongue, pharyngeal wall, tonsils, middle ear, external auditory canal, and auricle. It also supplies baroreceptors and chemoreceptors of the carotid sinus.
The facial nerve, the seventh cranial nerve, supplies the muscles of facial expression, taste from the anterior two-thirds of the tongue, and sensation from parts of the external acoustic meatus, auricle, and retro-auricular area. It also provides parasympathetic fibers to the submandibular gland, sublingual gland, nasal glands, and lacrimal glands.
The hypoglossal nerve, the twelfth cranial nerve, supplies the intrinsic muscles of the tongue and all but one of the extrinsic muscles of the tongue.
The greater auricular nerve is a superficial cutaneous branch of the cervical plexus that supplies sensation to the capsule of the parotid gland, skin overlying the gland, and skin over the mastoid process and outer ear.
The mandibular nerve, the third division of the trigeminal nerve, carries sensory and motor fibers. It carries sensation from the lower lip, lower teeth and gingivae, chin, and jaw. It also supplies motor innervation to the muscles of mastication, mylohyoid, the anterior belly of digastric, tensor veli palatini, and tensor tympani.
The patient in the question has sialadenosis, a benign, non-inflammatory enlargement of a salivary gland, in the parotid glands, which can be caused by bulimia nervosa.
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.
-
This question is part of the following fields:
- Gastrointestinal System
-
-
Question 29
Correct
-
A woman undergoes a high anterior resection for carcinoma of the upper rectum. Which one of the following vessels will require ligation?
Your Answer: Inferior mesenteric artery
Explanation:Anterior resection typically involves dividing the IMA, which is necessary for oncological reasons and also allows for adequate mobilization of the colon for anastomosis.
The colon begins with the caecum, which is the most dilated segment of the colon and is marked by the convergence of taenia coli. The ascending colon follows, which is retroperitoneal on its posterior aspect. The transverse colon comes after passing the hepatic flexure and becomes wholly intraperitoneal again. The splenic flexure marks the point where the transverse colon makes an oblique inferior turn to the left upper quadrant. The descending colon becomes wholly intraperitoneal at the level of L4 and becomes the sigmoid colon. The sigmoid colon is wholly intraperitoneal, but there are usually attachments laterally between the sigmoid and the lateral pelvic sidewall. At its distal end, the sigmoid becomes the upper rectum, which passes through the peritoneum and becomes extraperitoneal.
The arterial supply of the colon comes from the superior mesenteric artery and inferior mesenteric artery, which are linked by the marginal artery. The ascending colon is supplied by the ileocolic and right colic arteries, while the transverse colon is supplied by the middle colic artery. The descending and sigmoid colon are supplied by the inferior mesenteric artery. The venous drainage comes from regional veins that accompany arteries to the superior and inferior mesenteric vein. The lymphatic drainage initially follows nodal chains that accompany supplying arteries, then para-aortic nodes.
The colon has both intraperitoneal and extraperitoneal segments. The right and left colon are part intraperitoneal and part extraperitoneal, while the sigmoid and transverse colon are generally wholly intraperitoneal. The colon has various relations with other organs, such as the right ureter and gonadal vessels for the caecum/right colon, the gallbladder for the hepatic flexure, the spleen and tail of pancreas for the splenic flexure, the left ureter for the distal sigmoid/upper rectum, and the ureters, autonomic nerves, seminal vesicles, prostate, and urethra for the rectum.
-
This question is part of the following fields:
- Gastrointestinal System
-
-
Question 30
Incorrect
-
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: Internal iliac artery
Correct 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.
-
This question is part of the following fields:
- Gastrointestinal System
-
-
Question 31
Incorrect
-
A 65-year-old man comes to the emergency department with a significant swelling in his abdomen. He confesses to consuming more alcohol since losing his job five years ago, but he has no other significant medical history.
During the examination, the doctor observes shifting dullness. To confirm the suspicion of portal hypertension, the doctor orders liver function tests and an ascitic tap (paracentesis).
What result from the tests would provide the strongest indication of portal hypertension?Your Answer: Serum-ascites albumin gradient (SAAG) of 4.5 g/L
Correct Answer: Serum-ascites albumin gradient (SAAG) of 13.1 g/L
Explanation:Ascites is a medical condition characterized by the accumulation of abnormal amounts of fluid in the abdominal cavity. The causes of ascites can be classified into two groups based on the serum-ascites albumin gradient (SAAG) level. If the SAAG level is greater than 11g/L, it indicates portal hypertension, which is commonly caused by liver disorders such as cirrhosis, alcoholic liver disease, and liver metastases. Other causes of portal hypertension include cardiac conditions like right heart failure and constrictive pericarditis, as well as infections like tuberculous peritonitis. On the other hand, if the SAAG level is less than 11g/L, ascites may be caused by hypoalbuminaemia, malignancy, pancreatitis, bowel obstruction, and other conditions.
The management of ascites involves reducing dietary sodium and sometimes fluid restriction if the sodium level is less than 125 mmol/L. Aldosterone antagonists like spironolactone are often prescribed, and loop diuretics may be added if necessary. Therapeutic abdominal paracentesis may be performed for tense ascites, and large-volume paracentesis requires albumin cover to reduce the risk of complications. Prophylactic antibiotics may also be given to prevent spontaneous bacterial peritonitis. In some cases, a transjugular intrahepatic portosystemic shunt (TIPS) may be considered.
-
This question is part of the following fields:
- Gastrointestinal System
-
-
Question 32
Incorrect
-
A 23-year-old woman presents to her GP with a 3-month history of fatigue, breathlessness on exertion, skin pallor, and a swollen, painful tongue. She has also been experiencing bloating, diarrhoea, and stomach pain.
On examination her respiratory rate was 18/min at rest, oxygen saturation 99%, blood pressure 120/80 mmHg and temperature 37.1ºC. Her abdomen was generally tender and distended.
The results of a blood test are as follows:
Hb 90 g/L Male: (135-180)
Female: (115 - 160)
Ferritin 8 ng/mL (20 - 230)
Vitamin B12 120 ng/L (200 - 900)
Folate 2.0 nmol/L (> 3.0)
What investigation would be most likely to determine the diagnosis?Your Answer: Intrinsic factor antibodies
Correct Answer: Tissue transglutaminase antibodies (anti-TTG) and total immunoglobulin A levels (total IgA)
Explanation: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.
-
This question is part of the following fields:
- Gastrointestinal System
-
-
Question 33
Correct
-
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.
-
This question is part of the following fields:
- Gastrointestinal System
-
-
Question 34
Correct
-
A 32-year-old man visits his GP reporting a recent onset tremor, along with difficulties in coordination, slurred speech, and deteriorating handwriting. The patient denies experiencing any weakness, visual impairment, or dizziness. Following a battery of blood tests, the diagnosis of Wilson's disease is confirmed.
Which region of the brain is typically impacted in this disorder?Your Answer: Basal ganglia
Explanation:Wilson’s disease causes elevated copper levels in the body, leading to deposits in various organs, with the basal ganglia in the brain being the most commonly affected. Damage to this structure results in symptoms. Broca’s area in the frontal lobe is involved in language production and is commonly affected in stroke. The midbrain is involved in consciousness and movement, while the motor cortex is involved in planning and executing movement. The ventricles are fluid-filled spaces involved in cerebrospinal fluid movement and formation.
Understanding Wilson’s Disease
Wilson’s disease is a genetic disorder that causes excessive copper accumulation in the tissues due to metabolic abnormalities. It is an autosomal recessive disorder caused by a defect in the ATP7B gene located on chromosome 13. Symptoms usually appear between the ages of 10 to 25 years, with children presenting with liver disease and young adults with neurological disease.
The disease is characterised by excessive copper deposition in the tissues, particularly in the brain, liver, and cornea. This can lead to a range of symptoms, including hepatitis, cirrhosis, basal ganglia degeneration, speech and behavioural problems, asterixis, chorea, dementia, parkinsonism, Kayser-Fleischer rings, renal tubular acidosis, haemolysis, and blue nails.
To diagnose Wilson’s disease, doctors may perform a slit lamp examination for Kayser-Fleischer rings, measure serum ceruloplasmin and total serum copper (which is often reduced), and check for increased 24-hour urinary copper excretion. Genetic analysis of the ATP7B gene can confirm the diagnosis.
Treatment for Wilson’s disease typically involves chelating agents such as penicillamine or trientine hydrochloride, which help to remove excess copper from the body. Tetrathiomolybdate is a newer agent that is currently under investigation. With proper management, individuals with Wilson’s disease can lead normal lives.
-
This question is part of the following fields:
- Gastrointestinal System
-
-
Question 35
Correct
-
A 65-year-old male is undergoing a Whipples procedure for adenocarcinoma of the pancreas. During the mobilisation of the pancreatic head, the surgeons come across a large vessel passing over the anterior aspect of the uncinate process. What is the probable identity of this vessel?
Your Answer: Superior mesenteric artery
Explanation:The origin of the superior mesenteric artery is the aorta, and it travels in front of the lower section of the pancreas. If this area is invaded, it is not recommended to undergo resectional surgery.
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.
-
This question is part of the following fields:
- Gastrointestinal System
-
-
Question 36
Incorrect
-
A 16-year-old boy presents to his GP with a 5-month history of passing frequent watery diarrhoea, up to 6 times a day. He reports occasional passage of mucus mixed with his stool and has experienced a weight loss of around 9kg. An endoscopy and biopsy are performed, revealing evidence of granuloma formation.
What is the probable diagnosis?Your Answer: Colonic tuberculosis
Correct Answer: Crohn’s disease
Explanation:The presence of granulomas in the gastrointestinal tract is a key feature of Crohn’s disease, which is a chronic inflammatory condition that can affect any part of the digestive system. The combination of granulomas and clinical history is highly indicative of this condition.
Coeliac disease, on the other hand, is an autoimmune disorder triggered by gluten consumption that causes villous atrophy and malabsorption. However, it does not involve the formation of granulomas.
Colonic tuberculosis, caused by Mycobacterium tuberculosis, is another granulomatous condition that affects the ileocaecal valve. However, the granulomas in this case are caseating with necrosis, and colonic tuberculosis is much less common than Crohn’s disease.
Endoscopy and biopsy are not necessary for diagnosing irritable bowel syndrome, as they are primarily used to rule out other conditions. Biopsies in irritable bowel syndrome would not reveal granuloma formation.
Ulcerative colitis, another inflammatory bowel disease, is characterized by crypt abscesses, pseudopolyps, and mucosal ulceration that can cause rectal bleeding. However, granulomas are not present in this condition.
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.
-
This question is part of the following fields:
- Gastrointestinal System
-
-
Question 37
Incorrect
-
A 65-year-old patient loses 1.6L of fresh blood from their abdominal drain. Which of the following will not decrease?
Your Answer: Cardiac output
Correct Answer: Renin secretion
Explanation:Renin secretion is likely to increase when there is systemic hypotension leading to a decrease in renal blood flow. While the kidney can regulate its own blood flow within a certain range of systemic blood pressures, a reduction of 1.6 L typically results in an elevation of renin secretion.
Shock is a condition where there is not enough blood flow to the tissues. There are five main types of shock: septic, haemorrhagic, neurogenic, cardiogenic, and anaphylactic. Septic shock is caused by an infection that triggers a particular response in the body. Haemorrhagic shock is caused by blood loss, and there are four classes of haemorrhagic shock based on the amount of blood loss and associated symptoms. Neurogenic shock occurs when there is a disruption in the autonomic nervous system, leading to decreased vascular resistance and decreased cardiac output. Cardiogenic shock is caused by heart disease or direct myocardial trauma. Anaphylactic shock is a severe, life-threatening allergic reaction. Adrenaline is the most important drug in treating anaphylaxis and should be given as soon as possible.
-
This question is part of the following fields:
- Gastrointestinal System
-
-
Question 38
Incorrect
-
A 17-year-old girl comes to the emergency department complaining of nausea and vomiting. A medical trainee, who has recently started her emergency rotation, prescribes metoclopramide to alleviate her symptoms before ordering some tests.
The nurse cautions the doctor that metoclopramide is not recommended for young female patients and suggests switching to cyclizine.
What is the reason for metoclopramide being unsuitable for this patient?Your Answer: Risk of respiratory depression
Correct Answer: Risk of oculogyric crisis
Explanation:Metoclopramide use in children and young adults can lead to oculogyric crisis, which is a dystonic reaction that causes the eyes to involuntarily gaze upwards for an extended period. Opioids can cause respiratory depression, while cyclizine may result in restlessness and urinary retention. Amiodarone use may cause slate-grey skin discoloration. Additionally, metoclopramide can increase urinary frequency.
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.
-
This question is part of the following fields:
- Gastrointestinal System
-
-
Question 39
Incorrect
-
You are on a post-take ward round with your consultant and review a 50-year-old man who was admitted with sudden severe abdominal pain, confusion and pyrexia. He has a history of alcoholic cirrhosis and known asymptomatic ascites. An ascitic tap was performed overnight which revealed a neutrophil count of 375/mm³ and was sent for urgent microscopy & culture.
What is the most probable organism to be cultured from the ascitic tap?Your Answer: Klebsiella
Correct Answer: E. coli
Explanation:The most frequently isolated organism in ascitic fluid culture in cases of spontaneous bacterial peritonitis is E. coli. While Staphylococcus aureus, Klebsiella, and Streptococcus can also cause spontaneous bacterial peritonitis, they are not as commonly found as E. coli.
Understanding Spontaneous Bacterial Peritonitis
Spontaneous bacterial peritonitis (SBP) is a type of peritonitis that typically affects individuals with ascites caused by liver cirrhosis. The condition is characterized by symptoms such as abdominal pain, fever, and ascites. Diagnosis is usually made through paracentesis, which reveals a neutrophil count of over 250 cells/ul. The most common organism found on ascitic fluid culture is E. coli.
Management of SBP typically involves the administration of intravenous cefotaxime. Antibiotic prophylaxis is recommended for patients with ascites who have had an episode of SBP or have fluid protein levels below 15 g/l and a Child-Pugh score of at least 9 or hepatorenal syndrome. NICE recommends prophylactic oral ciprofloxacin or norfloxacin until the ascites has resolved.
Alcoholic liver disease is a significant predictor of poor prognosis in SBP. Understanding the symptoms, diagnosis, and management of SBP is crucial for healthcare professionals to provide appropriate care for patients with this condition. Proper management can help improve outcomes and prevent complications.
-
This question is part of the following fields:
- Gastrointestinal System
-
-
Question 40
Correct
-
A 25-year-old man is suspected of having an inflamed Meckel's diverticulum. Where is it most likely to be located?
Your Answer: Approximately 60 cm proximal to the ileocaecal valve
Explanation:The length of these growths is 2 inches (5cm), and they are twice as common in men. They involve two types of tissue and are located approximately 2 feet (60cm) from the ileocaecal valve.
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.
-
This question is part of the following fields:
- Gastrointestinal System
-
-
Question 41
Incorrect
-
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: Jejunum
Correct 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.
-
This question is part of the following fields:
- Gastrointestinal System
-
-
Question 42
Correct
-
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.
-
This question is part of the following fields:
- Gastrointestinal System
-
-
Question 43
Incorrect
-
A 4-day old neonate with Down's syndrome is experiencing excessive vomiting during their stay in the ward. The mother had an uncomplicated full-term pregnancy. The baby has not yet had their first bowel movement, causing increased concern for the parents. Upon examination, there is slight abdominal distension. Where is the site of pathology within the colon?
Your Answer: Sub mucosa
Correct Answer: Muscularis propria externa
Explanation:The myenteric nerve plexus, also known as Auerbach’s plexus, is located within the muscularis externa, which is one of the four layers of the bowel. In neonates with Hirschsprung disease, there is a lack of ganglion cells in the myenteric plexus, resulting in a lack of peristalsis and symptoms such as nausea, vomiting, bloating, and delayed passage of meconium. This condition is more common in males and children with Down’s syndrome.
The four layers of the bowel, from deep to superficial, are the mucosa, submucosa, muscularis propria (externa), and serosa. The muscularis externa contains two layers of smooth muscle, the inner circular layer and the outer longitudinal layer, with the myenteric plexus located between them. The mucosa also contains a thin layer of connective tissue called the lamina propria.
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.
-
This question is part of the following fields:
- Gastrointestinal System
-
-
Question 44
Correct
-
A 16-year-old female was admitted to the paediatric unit with a history of anorexia nervosa and a body mass index of 16kg/m². Despite being uncooperative initially, she has shown improvement in her willingness to participate with the team. However, she now presents with complaints of abdominal pain and weakness. Upon blood testing, the following results were obtained:
Hb 125 g/L Male: (135-180) Female: (115 - 160)
Platelets 180 * 109/L (150 - 400)
WBC 4.5 * 109/L (4.0 - 11.0)
Na+ 138 mmol/L (135 - 145)
K+ 3.2 mmol/L (3.5 - 5.0)
Bicarbonate 26 mmol/L (22 - 29)
Urea 5 mmol/L (2.0 - 7.0)
Creatinine 70 µmol/L (55 - 120)
Calcium 2.1 mmol/L (2.1-2.6)
Phosphate 0.5 mmol/L (0.8-1.4)
Magnesium 0.6 mmol/L (0.7-1.0)
What is the likely cause of the patient's abnormal blood results?Your Answer: Extended period of low calories then high carbohydrate intake
Explanation:Refeeding syndrome can occur in patients who have experienced prolonged catabolism and then suddenly switch to carbohydrate metabolism. This can lead to a rapid uptake of phosphate, potassium, and magnesium into the cells, caused by spikes in insulin and glucose. Patients with low BMI and poor nutritional intake over a long period of time are at a higher risk. Taking vitamin tablets would not affect blood results, but excessive intake can result in hypervitaminosis. While exogenous insulin could also cause this syndrome, there is no indication that the patient has taken it. To reduce the risk of refeeding syndrome, some patients may be advised to follow initial high-fat, low-carbohydrate diets.
Understanding Refeeding Syndrome
Refeeding syndrome is a condition that occurs when a person who has been starved for an extended period suddenly begins to eat again. This metabolic abnormality is caused by the abrupt switch from catabolism to carbohydrate metabolism. The consequences of refeeding syndrome include hypophosphataemia, hypokalaemia, hypomagnesaemia, and abnormal fluid balance, which can lead to organ failure.
To prevent refeeding syndrome, it is important to identify patients who are at high risk of developing the condition. According to guidelines produced by NICE in 2006, patients are considered high-risk if they have a BMI of less than 16 kg/m2, have experienced unintentional weight loss of more than 15% over 3-6 months, have had little nutritional intake for more than 10 days, or have hypokalaemia, hypophosphataemia, or hypomagnesaemia prior to feeding (unless high).
If a patient has two or more of the following risk factors, they are also considered high-risk: a BMI of less than 18.5 kg/m2, unintentional weight loss of more than 10% over 3-6 months, little nutritional intake for more than 5 days, or a history of alcohol abuse, drug therapy (including insulin, chemotherapy, diuretics, and antacids).
To prevent refeeding syndrome, NICE recommends that patients who haven’t eaten for more than 5 days should be re-fed at no more than 50% of their requirements for the first 2 days. By following these guidelines, healthcare professionals can help prevent the potentially life-threatening consequences of refeeding syndrome.
-
This question is part of the following fields:
- Gastrointestinal System
-
-
Question 45
Incorrect
-
Which one of the following is not a result of somatostatin?
Your Answer: It decreases pepsin secretion
Correct Answer: It stimulates pancreatic acinar cells to release lipase
Explanation: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.
-
This question is part of the following fields:
- Gastrointestinal System
-
-
Question 46
Correct
-
A 30-year-old male presents with massive haematemesis and is diagnosed with splenomegaly. What is the probable origin of the bleeding?
Your Answer: Oesophageal varices
Explanation:Portal Hypertension and its Manifestations
Portal hypertension is a condition that often leads to splenomegaly and upper gastrointestinal (GI) bleeding. The primary cause of bleeding is oesophageal varices, which are dilated veins in the oesophagus. In addition to these symptoms, portal hypertension can also cause ascites, a buildup of fluid in the abdomen, and acute or chronic hepatic encephalopathy, a neurological disorder that affects the brain. Another common manifestation of portal hypertension is splenomegaly with hypersplenism, which occurs when the spleen becomes enlarged and overactive, leading to a decrease in the number of blood cells in circulation. the various symptoms of portal hypertension is crucial for early diagnosis and effective management of the condition.
-
This question is part of the following fields:
- Gastrointestinal System
-
-
Question 47
Correct
-
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.
-
This question is part of the following fields:
- Gastrointestinal System
-
-
Question 48
Incorrect
-
An older gentleman was discovered to have an asymptomatic midline abdominal mass. What physical feature during examination would suggest a diagnosis of an abdominal aortic aneurysm (AAA)?
Your Answer: Firm
Correct Answer: Expansile
Explanation:Abdominal Aortic Aneurysm:
An abdominal aortic aneurysm (AAA) is frequently found incidentally in men, particularly in older age groups. As a result, ultrasound screening has been introduced in many areas to detect this condition. However, the diagnosis of AAA cannot be made based on pulsatility alone, as it is common for pulsations to be transmitted by the organs that lie over the aorta. Instead, an AAA is characterized by its expansile nature. If a tender, pulsatile swelling is present, it may indicate a perforated AAA, which is a medical emergency. Therefore, it is important for men to undergo regular screening for AAA to detect and manage this condition early. -
This question is part of the following fields:
- Gastrointestinal System
-
-
Question 49
Incorrect
-
Which of the following hemodynamic changes is not observed in hypovolemic shock?
Your Answer: Reduced left ventricle filling pressures
Correct Answer: Reduced systemic vascular resistance
Explanation:Cardiogenic shock can occur due to conditions such as a heart attack or valve abnormality. This can lead to an increase in systemic vascular resistance (vasoconstriction in response to low blood pressure), an increase in heart rate (due to sympathetic response), a decrease in cardiac output, and a decrease in blood pressure. Hypovolemic shock can occur due to blood volume depletion from causes such as hemorrhage, vomiting, diarrhea, dehydration, or third-space losses during major surgeries. This can lead to an increase in systemic vascular resistance, an increase in heart rate, a decrease in cardiac output, and a decrease in blood pressure. Septic shock occurs when peripheral vascular dilatation causes a fall in systemic vascular resistance. This response can also occur in anaphylactic shock or neurogenic shock. In septic shock, there is a reduced systemic vascular resistance, an increased heart rate, a normal or increased cardiac output, and a decrease in blood pressure. Typically, systemic vascular resistance will decrease in septic shock.
Shock is a condition where there is not enough blood flow to the tissues. There are five main types of shock: septic, haemorrhagic, neurogenic, cardiogenic, and anaphylactic. Septic shock is caused by an infection that triggers a particular response in the body. Haemorrhagic shock is caused by blood loss, and there are four classes of haemorrhagic shock based on the amount of blood loss and associated symptoms. Neurogenic shock occurs when there is a disruption in the autonomic nervous system, leading to decreased vascular resistance and decreased cardiac output. Cardiogenic shock is caused by heart disease or direct myocardial trauma. Anaphylactic shock is a severe, life-threatening allergic reaction. Adrenaline is the most important drug in treating anaphylaxis and should be given as soon as possible.
-
This question is part of the following fields:
- Gastrointestinal System
-
-
Question 50
Incorrect
-
A 55-year-old man with a carcinoma of the lower third of the oesophagus is having an oesophagogastrectomy. During the mobilization of the lower part of the oesophagus, where is the thoracic duct most likely to be encountered by the surgeons?
Your Answer: On the right side of the oesophagus
Correct Answer: Posterior to the oesophagus
Explanation:The thoracic duct is situated at the back of the oesophagus and takes a leftward course at the Angle of Louis. It joins the aorta at T12 as it enters the thorax.
The Thoracic Duct: Anatomy and Clinical Significance
The thoracic duct is a continuation of the cisterna chyli located in the abdomen. It enters the thorax at the level of T12 and runs posterior to the esophagus for most of its intrathoracic course. At T5, it passes to the left side of the body. Lymphatics from the left side of the head and neck join the thoracic duct before it empties into the left brachiocephalic vein. In contrast, lymphatics from the right side of the head and neck drain into the right lymphatic duct, which eventually empties into the right brachiocephalic vein via the mediastinal trunk.
The thoracic duct’s location in the thorax makes it vulnerable to injury during oesophageal surgery. To avoid damaging the duct, some surgeons apply cream to patients before oesophagectomy to help identify the cut ends of the duct. Understanding the anatomy and clinical significance of the thoracic duct is essential for healthcare professionals involved in thoracic surgery and lymphatic drainage disorders.
-
This question is part of the following fields:
- Gastrointestinal System
-
00
Correct
00
Incorrect
00
:
00
:
00
Session Time
00
:
00
Average Question Time (
Mins)