-
Question 1
Incorrect
-
Which of the following statements is considered correct regarding Hepatitis B vaccination?
Your Answer: A peak titre above 10 mIU/ml is regarded as a good response
Correct Answer: The vaccine should be stored between 2 and 8 degrees Centigrade
Explanation:Hepatitis B vaccine should be stored at 35°-46° F (2°-8° C) and should not be frozen.There is no association between hepatitis B vaccination and Guillain-Barre syndrome. Infection with the bacterium Campylobacter jejuni is one of the most common risk factors for GBS. People can also develop GBS after having the flu or other infections (such as cytomegalovirus and Epstein Barr virus).Hepatitis B vaccine is prepared from initial concentration of surface antigen.To ensure adequate immunity, anti-HBs (HBsAb) titres may be checked 4-8 weeks following the last shot of the hepatitis B vaccine series.
-
This question is part of the following fields:
- Microbiology
- Principles Of Microbiology
-
-
Question 2
Incorrect
-
A 29 year old patient with known inflammatory bowel disease presents to ED with surgical complications following his recent ileocaecal resection. Removal of the terminal ileum may result in the malabsorption of which of the following:
Your Answer: Folate
Correct Answer: Vitamin B12
Explanation:On ingestion, vitamin B12 is bound to R protein found in saliva and gastric secretions, which protects it from digestion in the stomach. Intrinsic factor is secreted by gastric parietal cells. Receptors for the IF-B12 complex are present in the membrane of epithelial cells of the terminal ileum, which bind the complex and allow uptake of vitamin B12 across the apical membrane by endocytosis. Vitamin B12 is then transported across the basal membrane into the portal blood where it is bound to transcobalamin II and processed by the liver. In pernicious anaemia, there are autoantibodies against gastric parietal cells and intrinsic factor, resulting in vitamin B12 deficiency anaemia.
-
This question is part of the following fields:
- Gastrointestinal
- Physiology
-
-
Question 3
Incorrect
-
A dermatological examination of a patient who has presented with a lump shows a collection of boils clustered together.Which one of these best describes the lump you have found on examination?
Your Answer: Furuncle
Correct Answer: Carbuncle
Explanation:A furuncle, or boil, is a pyogenic infection of the hair follicle commonly caused by infection with Staphylococcus aureus. A carbuncle is a collection of individual boils clustered together. A bulla is a visible collection of clear fluid measuring greater than 0.5 cm in diameter. A vesicle is a visible collection of clear fluid measuring less than 0.5 cm in diameter.A pustule is a small visible skin elevation containing an accumulation of pus.
-
This question is part of the following fields:
- General Pathology
- Pathology
-
-
Question 4
Incorrect
-
For the treatment of his atrial fibrillation, a 67-year-old man is about to begin taking warfarin. He also takes a number of other medications.Which of the following medications will prevent warfarin from working?
Your Answer: Ciprofloxacin
Correct Answer: Phenytoin
Explanation:Many medications, including warfarin, require cytochrome P450 enzymes for their metabolism. When co-prescribing cytochrome p450 enzyme inducers and inhibitors with warfarin, it’s critical to be cautious.Inhibitors of the cytochrome p450 enzyme inhibit the effects of warfarin, resulting in a lower INR. To remember the most commonly encountered cytochrome p450 enzyme inducers, use the mnemonic PC BRASS:P– PhenytoinC– CarbamazepineB– BarbituratesR– RifampicinA– Alcohol (chronic ingestion)S– SulphonylureasS– Smoking
-
This question is part of the following fields:
- Cardiovascular Pharmacology
- Pharmacology
-
-
Question 5
Correct
-
You've been asked to visit a 20-year-old patient  who has been complaining of stomach pain, diarrhoea, and bloating. The GP recently saw the patient and is now looking into numerous possible reasons for stomach hypermotility.Which of the following factors contributes to increased stomach motility?
Your Answer: Gastrin
Explanation:Gastrin is a peptide hormone that aids in gastric motility by stimulating the generation of gastric acid by the parietal cells of the stomach. G-cells in the stomach’s pyloric antrum, the duodenum, and the pancreas release it.The following stimuli cause the release of gastrin:Stimulation of the vagus nerveHypercalcaemiastomach bloatingProteins that have been partially digested, particularly amino acids.The presence of acid and somatostatin inhibits the release of gastrin.Gastrin’s main actions are as follows:Gastric parietal cells are stimulated to release hydrochloric acid.ECL cells are stimulated to produce histamine.Gastric parietal cell maturation and fundal growth stimulationCauses the secretion of pepsinogen by the gastric chief cells.Improves antral muscle mobility stimulates gastric contractionsIncreases gastric emptying rate and stimulates pancreatic secretionGallbladder emptying is induced.
-
This question is part of the following fields:
- Gastrointestinal Physiology
- Physiology
-
-
Question 6
Incorrect
-
Which nerve innervates the brachioradialis muscle?
Your Answer: The median nerve
Correct Answer: The radial nerve
Explanation:Brachioradialis is innervated by the radial nerve (from the root values C5-C6) that stems from the posterior cord of the brachial plexus.
-
This question is part of the following fields:
- Anatomy
- Upper Limb
-
-
Question 7
Incorrect
-
A 6-year-old girl is brought into the paediatric emergency room by her mother in a state of high-grade fever and extreme irritability. She is also reluctant to urinate as it is associated with lower abdominal pain and stinging. She has no history of any UTIs requiring antibiotics in the past 12 months. The urine sensitivity test report is still unavailable. A clean catch urine sample is taken for urine dipstick, which reveals the presence of blood, protein, leukocytes and nitrites. Fresh blood tests were sent, and her estimated GFR is calculated to be 40 ml/minute. Out of the following, which antibiotic is most appropriate to be prescribed to this patient?
Your Answer: Cefalexin
Correct Answer: Trimethoprim
Explanation:The NICE guidelines for children and young people under 16 years lower UTIs are:1. Get a urine sample before antibiotics are taken, and do a dipstick test OR send for culture and susceptibility2. Assess and manage children under 5 with lower UTI with fever as recommended in the NICE guideline on fever in under 5s.3. Prescribe an immediate antibiotic prescription and take into account the previous urine culture and susceptibility results, previous antibiotic use, which may have led to resistant bacteria4. If urine culture and susceptibility report is sent- Review the choice of antibiotic when the results are available AND- change the antibiotic according to susceptibility results if the bacteria are resistant and symptoms are not improving, using a narrow-spectrum antibiotic wherever possibleThe choice of antibiotics for non-pregnant young people under 16 years with lower UTI is summarised below:1. Children under 3 months:- Refer to paediatric specialist and treat with intravenous antibiotic in line with NICE guideline on fever in under 5s2. Children over 3 months: – First-choice Nitrofurantoin – if eGFR >45 ml/minuteTrimethoprim – (if low risk of resistance*)- Second-choice (no improvement in lower UTI symptoms on first-choice for at least 48 hours, or when first-choice not suitable)Nitrofurantoin – if eGFR >45 ml/minute and not used as first-choiceAmoxicillin (only if culture results available and susceptible)Cefalexin
-
This question is part of the following fields:
- Infections
- Pharmacology
-
-
Question 8
Correct
-
A 55-year-old woman with history of gastritis and reflux esophagitis tested positive for Helicobacter pylori infection. Which of the following statements regarding Helicobacter pylori is considered true?
Your Answer: It is helix shaped
Explanation:Helicobacter pylori is a curved or helix-shaped, non-spore forming, Gram-negative, microaerophilic bacteria. It is motile, having multiple flagella at one pole. It has a lipopolysaccharide component in its outer membrane.
-
This question is part of the following fields:
- Microbiology
- Specific Pathogen Groups
-
-
Question 9
Correct
-
A 58-year-old woman presents with symptoms of increase in weight, proximal muscular weakening and withering, easy bruising, and acne. You notice that she has a full, plethoric aspect to her face, as well as significant supraclavicular fat pads, when you examine her. She has previously been diagnosed with Cushing's syndrome.Cushing's syndrome is most commonly caused by which of the following?
Your Answer: Iatrogenic administration of corticosteroids
Explanation:Cushing’s syndrome is a group of symptoms and signs brought on by long-term exposure to high amounts of endogenous or exogenous glucocorticoids. Cushing’s syndrome affects about 10-15 persons per million, and it is more common in those who have had a history of obesity, hypertension, or diabetes.Iatrogenic corticosteroid injection is the most prevalent cause of Cushing’s syndrome. Cushing’s illness is the second most prevalent cause of Cushing’s syndrome. Cushing’s disease is distinct from Cushing’s syndrome in that it refers to a single cause of the illness, a pituitary adenoma that secretes high quantities of ACTH, which raises cortisol levels.Cushing’s syndrome has several endogenous sources, including:Cushing’s disease is caused by a pituitary adenoma.Adrenal adenoma Ectopic corticotropin syndrome, e.g. small cell cancer of the lungAdrenal carcinoma is a cancer of the adrenal gland.Hyperplasia of the adrenal glands
-
This question is part of the following fields:
- Endocrine Physiology
- Physiology
-
-
Question 10
Incorrect
-
A 30-year old male is taken to the emergency room after suffering a blunt trauma to the abdomen. He is complaining of severe abdominal pain, however all his other vital signs remain stable. A FAST scan is performed to assess for hemoperitoneum.If hemoperitoneum is present, it is most likely to be observed in which of the following areas?
Your Answer: Spleen
Correct Answer: Liver
Explanation:The Focused Assessment with Sonography in Trauma (FAST) is an ultrasound protocol developed to assess for hemoperitoneum and hemopericardium. Numerous studies have demonstrated sensitivities between 85% to 96% and specificities exceeding 98%.The FAST exam evaluates four regions for pathologic fluid: (1) the right upper quadrant, (2) the subxiphoid (or subcostal) view, (3) the left upper quadrant, and (4) the suprapubic region.The right upper quadrant (RUQ) visualizes the hepatorenal recess, also known as Morrison’s pouch, the right paracolic gutter, the hepato-diaphragmatic area, and the caudal edge of the left liver lobe. The probe is positioned in the sagittal orientation along the patient’s flank at the level of the 8 to 11 rib spaces. The hand is placed against the bed to ensure visualization of the retroperitoneal kidney. The RUQ view is the most likely to detect free fluid with an overall sensitivity of 66%. Recent retrospective evidence suggests the area along the caudal edge of the left lobe of the liver has the highest sensitivity, exceeding 93%.
-
This question is part of the following fields:
- Abdomen And Pelvis
- Anatomy
-
-
Question 11
Incorrect
-
Regarding gas exchange at the alveolar-capillary membrane, which of the following statements is CORRECT:
Your Answer: Rate of diffusion is primarily dependent on the alveolar-capillary concentration gradient of O 2 and CO 2 .
Correct Answer: The rate of diffusion in lungs can be estimated by measuring the diffusing capacity of the lungs for carbon monoxide.
Explanation:Gas exchange between alveolar air and blood in the pulmonary capillaries takes place by diffusion across the alveolar-capillary membrane. Diffusion occurs from an area of high partial pressure to an area of low partial pressure, thus the driving force for diffusion is the alveolar-capillary partial pressure gradient. Diffusion occurs across a membrane and is therefore governed by Fick’s law. Although CO2is larger than O2, it is is much more soluble and diffuses 20 times more rapidly. The diffusing capacity for oxygen (DLO2) cannot be measured directly but the rate of diffusion in the lungs can be estimated by measuring the diffusing capacity of the lungs for carbon monoxide (DLCO).
-
This question is part of the following fields:
- Physiology
- Respiratory
-
-
Question 12
Correct
-
A young female was diagnosed with a urinary tract infection and was sent home with medications. However, after 48 hours of discharge, she returned to the hospital because there had been no relief from her symptoms. She is pregnant in her second trimester. The urine sensitivity test report is still unavailable. Fresh blood tests were sent, and her estimated GFR is calculated to be >60 ml/minute. She was prescribed nitrofurantoin 100 mg modified-release orally twice a day for two days.Out of the following, which antibiotic is most appropriate to be prescribed to this patient?
Your Answer: Cefalexin
Explanation:The NICE guidelines for pregnant women with lower UTIs are:1. Prescribe an antibiotic immediately, taking into account the previous urine culture and susceptibility results or avoiding past antibiotics that may have caused resistance2. Obtain a midstream urine sample before starting antibiotics and send for urine culture and susceptibility – Review the choice of antibiotic when the results are available – change the antibiotic according to susceptibility results if the bacteria are resistant, using a narrow-spectrum antibiotic wherever possibleThe first choice of antibiotics for pregnant women aged 12 years and over is:1. Nitrofurantoin100 mg modified-release PO BD for 3 days – if eGFR >45 ml/minuteThe second-choice (no improvement in lower UTI symptoms on first-choice for at least 48 hours, or when first-choice is not suitable) are:1. Amoxicillin 500 mg PO TDS for seven days (ONLY if culture results available and susceptible)2. Cefalexin500 mg BD for seven daysAlternative second-choices – consult local microbiologist, choose antibiotics based on culture and sensitivity results
-
This question is part of the following fields:
- Infections
- Pharmacology
-
-
Question 13
Incorrect
-
A 10-year-old girl that appears systemically well presents with a honey-crusted scab close to the corner of her mouth and states that the area is slightly itchy but not painful. The diagnosis given was impetigo.What is most likely the mode of transmission of the causative agent of the said diagnosis?
Your Answer: Vector transmission
Correct Answer: Direct contact
Explanation:Impetigo is a common pyoderma that is most often seen in children. Historically, most cases were caused by group A streptococci (GAS; Streptococcus pyogenes), although S. aureus has become the predominant pathogen over the last 15 years.A bullous form of impetigo accounts for approximately 10% of cases. It is caused by strains of S. aureus that produce exfoliative toxins leading to the formation of bullae, which quickly rupture and form a transparent, light brown crust.Impetigo is spread mainly by person-to-person contact; it is rapidly spread through direct transmission. The diagnosis of impetigo can be made from a Gram stain and culture of the vesicular contents.
-
This question is part of the following fields:
- Microbiology
- Principles Of Microbiology
-
-
Question 14
Correct
-
A 6-year-old girl is brought to the nephrology clinic by her mother due to facial oedema. Her lab workup shows proteinuria of 7 g/24 hours and serum albumin levels of 15 g/L. A diagnosis of Nephrotic Syndrome is made, and corticosteroid therapy is initiated. Which one of the following is the most likely cause of nephrotic syndrome in this patient?
Your Answer: Minimal change disease
Explanation:Minimal Change Disease is the most common cause of Nephrotic Syndrome in the paediatric population. It may be caused by NSAID use. Electron microscopy shows the fusion of foot processes while light microscopy will appear normal.Focal segmental glomerulosclerosis causes Nephrotic Syndrome in adults. It is associated with Heroin use and HIV infection. There is a limited response to steroids, and the disease progresses to end-stage renal failure in 5-10 years.Diabetic nephropathy occurs after a long period of diabetes due to the deposition of amyloid protein leading to a decrease in glomerular filtration. There is no history of Hepatitis B in this patient and no symptoms of liver disease such as jaundice. Membranous glomerulonephritis would present with features of Nephritic Syndrome. These would be oedema, haematuria; red blood cell casts in the urine and hypertension.
-
This question is part of the following fields:
- General Pathology
- Pathology
-
-
Question 15
Correct
-
Most of the lymph from vessels that drain the breast is collected in which of the following lymph nodes?
Your Answer: Axillary nodes
Explanation:Lymph is the fluid that flows through the lymphatic system. Axillary lymph nodes are near the breasts. They are often the first location to which breast cancer spreads if it moves beyond the breast tissue. They receive approximately 75% of lymph drainage from the breast via lymphatic vessels, laterally and superiorly. The lymph usually first drains to the anterior axillary nodes, and from here, through the central axillary, apical, and supraclavicular nodes in sequence.
-
This question is part of the following fields:
- Anatomy
- Upper Limb
-
-
Question 16
Incorrect
-
A 35 year old man presents with a deep laceration to the proximal part of the forearm. On further assessment, the patient is unable to flex the metacarpophalangeal joints and interphalangeal joints of the index, middle finger and the thumb. The ring and little fingers are intact but there is weakness at the proximal interphalangeal joint.There is also loss of sensation over the lateral palm and the palmar surface of the lateral three and a half fingers. Which of these nerve(s) has most likely been affected?
Your Answer: Ulnar nerve
Correct Answer: Median nerve
Explanation:A median nerve injury affecting the extrinsic and intrinsic muscles of the hand will present with:Loss of sensation to the lateral palm and the lateral three and a half fingers.Weakness of flexion at the metacarpophalangeal joints of the index and middle finger. This is because of paralysis of the lateral two lumbricals. Weakness of flexion of the proximal interphalangeal joints of all four fingers due to paralysis of the flexor digitorum superficialisWeakness of flexion at the distal interphalangeal joints of the index and middle finger following paralysis of the lateral half of the flexor digitorum profundus.Weakness of thumb flexion, abduction and opposition due to paralysis of the flexor pollicis longus and thenar muscles
-
This question is part of the following fields:
- Anatomy
- Upper Limb
-
-
Question 17
Incorrect
-
Which of the following is characterised by passive carrier-mediated transport down a chemical concentration gradient:
Your Answer: Primary active transport
Correct Answer: Facilitated diffusion
Explanation:Facilitated diffusion is the process of spontaneous passive transport of molecules or ions down their concentration gradient across a cell membrane via specific transmembrane transporter (carrier) proteins. The energy required for conformational changes in the transporter protein is provided by the concentration gradient rather than by metabolic activity.
-
This question is part of the following fields:
- Basic Cellular
- Physiology
-
-
Question 18
Incorrect
-
Which of these cell types in the stomach releases pepsinogen?
Your Answer: G-cells
Correct Answer: Chief cells
Explanation:The gastric chief cells in the stomach wall releases pepsinogen. Pepsinogen is a proenzyme. It mixes with hydrochloric acid in the stomach and is converted to pepsin. Pepsin breaks down proteins into peptides aiding protein digestion.
-
This question is part of the following fields:
- Gastrointestinal Physiology
- Physiology
-
-
Question 19
Correct
-
Metabolic hyperaemia harmonizes local blood flow with local O2 demand. If there is an increase in metabolic rate, the production of vasoactive metabolites increases. These metabolites act locally on the surrounding arterioles, causes vasodilation and an increase blood supply.Which of these metabolites is the most potent vasodilator in skeletal muscle?
Your Answer: K +
Explanation:Hyperaemia is the process where the body adjusts blood flow to meet the metabolic needs of different tissues in health and disease. Vasoactive mediators that take part in this process include K+, adenosine, CO2, H+, phosphates and H2O2. Although the mechanism is not clear, all these mediators likely contribute to some extent at different points.Specific organs are more sensitive to specific metabolites:K+ and adenosine are the most potent vasodilators in skeletal musclesCO2 and K+ are the most potent vasodilators in cerebral circulation.
-
This question is part of the following fields:
- Cardiovascular Physiology
- Physiology
-
-
Question 20
Incorrect
-
A pheochromocytoma is diagnosed in a 38-year-old female who has had episodes of acute sweating, palpitations, and paroxysmal hypertension.Which of the following is the MOST SUITABLE INITIAL TREATMENT?
Your Answer: Beta-blocker
Correct Answer: Alpha-blocker
Explanation:A phaeochromocytoma is a rare functional tumour that develops in the adrenal medulla from chromaffin cells. Extra-adrenal paragangliomas (extra-adrenal pheochromocytomas) are tumours that arise in the sympathetic nervous system’s ganglia and are closely connected to extra-adrenal paragangliomas (extra-adrenal pheochromocytomas). Catecholamines are secreted by these tumours, which generate a variety of symptoms and indications associated with sympathetic nervous system hyperactivity.Hypertension is the most prevalent presenting symptom, which can be continuous or intermittent.Symptoms are usually intermittent, occurring anywhere from many times a day to occasionally. The symptoms of the condition tend to grow more severe and frequent as the disease progresses.The ultimate therapy of choice is surgical resection, and if full resection is done without metastases, hypertension is typically cured.Preoperative medical treatment is critical because it lowers the risk of hypertensive crises during surgery. This is commonly accomplished by combining non-competitive alpha-blockers (such as phenoxybenzamine) with beta-blockers. To allow for blood volume expansion, alpha-blockade should be started at least 7-10 days before surgery. Beta-blockade, which helps to regulate tachycardia and some arrhythmias, can be started after this is accomplished. Hypertensive crises can be triggered if beta-blockade is started too soon.There should also be genetic counselling, as well as a search for and management of any linked illnesses.
-
This question is part of the following fields:
- Endocrine Physiology
- Physiology
-
-
Question 21
Correct
-
Which of the following nerves innervates the adductor brevis?
Your Answer: Obturator nerve
Explanation:Like the majority of the thigh adductors, adductor brevis is innervated by the obturator nerve. Obturator nerve is derived from the lumbar plexus (anterior branches of spinal nerves L2-L4).
-
This question is part of the following fields:
- Anatomy
- Lower Limb
-
-
Question 22
Correct
-
A 45-year-old businessman returns from a trip to West Africa with headaches and intermittent fevers. Thick and thin films are sent to the lab and a diagnosis is made of malaria. The patient is started on treatment but his condition deteriorates and he develops jaundice, renal failure and haemoglobinuria.Which of the following is the MOST likely causative organism? Select ONE answer only.
Your Answer: Plasmodium falciparum
Explanation:Malaria is an infectious disease transmitted by female of theAnophelesgenus of mosquito. It is a parasitic infection caused by the genusPlasmodium. Five species are recognized as causing disease in humans;Plasmodium falciparum,Plasmodium ovale,Plasmodium vivax,Plasmodium malariaeandPlasmodium knowlesi.The classic symptom of malaria is the malarial paroxysm, a cyclical occurrence of a cold phase, where the patient experiences intense chills, a hot stage, where the patient feels extremely hot and finally a sweating stage, where the fever declines and the patient sweats profusely. On examination the patient may show signs of anaemia, jaundice and have hepatosplenomegaly without evidence of lymphadenopathy.Plasmodium falciparum is the most serious form and is responsible for most deaths. Severe or complicated malaria is suggested by the presence of impaired consciousness, seizures, hypoglycaemia, anaemia, renal impairment, respiratory distress and spontaneous bleeding.Plasmodium falciparum is the most likely type in this case in view of the presentation.Haemoglobinuria and renal failure following treatment is suggestive of blackwater fever, which is caused byPlasmodium falciparum. An autoimmune reaction between the parasite and quinine causes haemolysis, haemoglobinuria, jaundice and renal failure. This can be fatal.The benign malarias: P.vivax, P. malariae and P.ovale are usually treated with chloroquine. A course of primaquine is also required in P.vivax and P.ovale infection. Artesunate is the drug treatment of choice for Plasmodium falciparum malaria. Quinine can still be used where artesunate is not available. Often combination therapy with drugs such as doxycycline or fansidar is also required.
-
This question is part of the following fields:
- Microbiology
- Specific Pathogen Groups
-
-
Question 23
Incorrect
-
Which of the following statements is correct regarding the partial pressure of oxygen during respiration?
Your Answer: Inhaled PO 2 < Humidified inspired PO 2
Correct Answer: Exhaled PO 2 > Alveolar PO 2
Explanation:Because of humidification, inspired PO2 in the airways is less than inhaled PO2. Because of gas exchange, alveolar PO2 is less than inhaled or inspired PO2.Because of mixing with anatomical dead space (air that has not taken part in gas exchange, exhaled PO2 is greater than alveolar O2, and therefore that has relatively higher PO2 on the way out, but is less than inhaled or inspired PO2.Typical values for a resting young healthy male (in kPa) are shown below:-Inhaled air: PO221.2, PCO20.0-Inspired air in airways (after humidification): PO219.9, PCO20.0-Alveolar air (after equilibrium with pulmonary capillaries): PO213.3, PCO25.3-Exhaled air (after mixing with anatomical dead space air): PO215.5, PCO24.3
-
This question is part of the following fields:
- Physiology
- Respiratory
-
-
Question 24
Correct
-
Which of the following is NOT a pharmacological effect of beta-blockers:
Your Answer: Reduced AV conduction time
Explanation:Effects of beta-blockers:Cardiovascular system: Reduce blood pressureReduce heart rate, contractility and cardiac outputIncrease AV conduction time, refractoriness and suppress automaticityEye:Reduce intraocular pressureRespiratory system:Cause bronchoconstriction
-
This question is part of the following fields:
- Cardiovascular
- Pharmacology
-
-
Question 25
Correct
-
A 23-year-old male presents to his family physician with the complaint of repeated episodes of abdominal pain and the passage of dark coloured urine every morning. He also reports increasing fatigue over the past several months. On examination, there are raised, painful red nodules over the skin of the back. Laboratory workup shows haemolytic anaemia, leukopenia and thrombocytopenia. Which one of the following disorders is this patient most likely to have?
Your Answer: Paroxysmal nocturnal haemoglobinuria
Explanation:Paroxysmal nocturnal haemoglobinuria is an acquired genetic disorder that causes a decrease in red blood cells due to a membrane defect that allows increased complement binding to RBCs, causing haemolysis. Patients complain of dark-coloured urine first in the morning due to haemoglobinuria secondary to lysis of red blood cells overnight. Thrombosis occurs, which affects hepatic, abdominal, cerebral and subdermal veins. Thrombosis of hepatic veins can lead to Budd-Chiari syndrome, thrombosis of subdermal veins can lead to painful nodules on the skin, and thrombosis of cerebral vessels can lead to stroke. The presence of dark urine in the morning only and at no other time differentiates this condition from other conditions.Multiple myeloma would present with bone pain, signs of radiculopathy if there were nerve root compression and a history of repeated infections. Patients with Non-Hodgkin Lymphoma would complain of enlarged lymph nodes, fatigue, fever, weight loss and a history of repeated infections. Acute lymphoblastic leukaemia presents more commonly in children than in adults. The patient would complain of bone pain, and on examination, there would be hepatosplenomegaly.
-
This question is part of the following fields:
- Haematology
- Pathology
-
-
Question 26
Incorrect
-
Which one of the listed cells are typically found in a granuloma?
Your Answer: Langerhan’s cells
Correct Answer: Epithelioid cells
Explanation:Typically, granuloma has Langhan’s cells (large multinucleated cells ) surrounded by epithelioid cell aggregates, T lymphocytes and fibroblasts.Antigen presenting monocytic cells found in the skin are known as Langerhan’s cells.
-
This question is part of the following fields:
- General Pathology
- Pathology
-
-
Question 27
Incorrect
-
A patient suffers from an injury to his hip and thigh. As a consequence of his injury, the nerve that was damaged innervates the obturator externus muscle.In which of the following nerves is the obturator externus muscle innervated by?
Your Answer: Anterior branch of the obturator nerve
Correct Answer: Posterior branch of the obturator nerve
Explanation:The obturator externus is innervated by the posterior branch of the obturator nerve, L2-L4.
-
This question is part of the following fields:
- Anatomy
- Lower Limb
-
-
Question 28
Incorrect
-
Regarding the power of a study, which of the following statements is INCORRECT:
Your Answer: The power of a study is increased with a larger significance level.
Correct Answer: The power of a study is not affected by data variability.
Explanation:A study should only be undertaken if the power is at least 80%; a study power set at 80% accepts a likelihood of 1 in 5 (20%) of missing a statistically significant difference where one exists.The determinants of power are:the sample size (the power increases with sample size)the variability of the observations (the power increases as the variability decreases)the effect size of interest (the power is greater for a larger expected effect size)and the significance level, α (the power is greater if the significance level is larger); therefore the probability of a type I error increases as the probability of a type II error decreases.
-
This question is part of the following fields:
- Evidence Based Medicine
- Statistics
-
-
Question 29
Correct
-
A 4-year-old girl is rushed to the Emergency Department by her grandparents after swallowing some of her grandfather's Warfarin tablets. On further questioning, it turns out that she took 5 of his 3 mg tablets which he needs to take due to a history of atrial fibrillation. The child appears healthy well-oriented in time, place and person, and has normal vitals. What is the threshold dose of Warfarin that needs to be ingested for there to be a risk of anticoagulation?
Your Answer: 0.5 mg/kg
Explanation:The clinical effects of Warfarin occur after a dose of greater than 0.5 mg/kg, and they will be observable 8-10 hours after consumption of the drug. The antidote used for Warfarin is Vitamin K.1. In low-risk cases with no apparent bleeding: an oral dose of 10 mg vitamin K2. If there is clinically significant bleedingan intravenous dose of 250-300 mcg/kgActivated charcoal: in cases of warfarin ingestionbinds to it and reduces the absorption of warfarin the ingestion must have occurred within the last hourThere is, however, rarely a need for the use of activated charcoal because vitamin K is such as safe and effective antidote. Clotting studies, including an INR, can be performed, but small children who have ingested warfarin do not require INRs or follow up if they have been treated with 10 mg vitamin K. This dose of vitamin will completely reverse the anticoagulative effects of warfarin.Perform INR if any of the following are present:1. Delayed presentation (>6 hours)2. Patients with symptoms or signs of anticoagulation3. Possible massive ingestion
-
This question is part of the following fields:
- Cardiovascular Pharmacology
- Pharmacology
-
-
Question 30
Incorrect
-
Nitric oxide release from endothelium is stimulated by all of the following EXCEPT for:
Your Answer: Bradykinin
Correct Answer: Noradrenaline
Explanation:Nitric oxide (NO) production by the endothelium is increased by factors that elevate intracellular Ca2+, including local mediators such as bradykinin, histamine and serotonin, and some neurotransmitters (e.g. substance P). Increased flow (shear stress) also stimulates NO production and additionally activates prostacyclin synthesis. The basal production of NO continuously modulates vascular resistance; increased production of nitric oxide acts to cause vasodilation. Nitric oxide also inhibits platelet activation and thrombosis.
-
This question is part of the following fields:
- Cardiovascular
- Physiology
-
SESSION STATS - PERFORMANCE PER SPECIALTY
