-
Question 1
Incorrect
-
A 29-year-old male presents with a 3-day history of bloody diarrhoea and abdominal pain.All the following are causes of infectious bloody diarrhoea EXCEPT?
Your Answer: Schistosoma mansoni
Correct Answer: Enterotoxigenic Escherichia coli
Explanation:Infective causes of bloody diarrhoea include:Salmonella sppCampylobacter sppSchistosomiasisEntamoeba histolytica (Amoebiasis )Shigella sppClostridium difficileYersinia sppEnteroinvasive Escherichia coliEnterotoxigenic Escherichia coli is non-invasive and does not cause inflammation of the gut and bloody diarrhoea. It presents with copious watery diarrhoea and usually are not associated with abdominal cramping.
-
This question is part of the following fields:
- Microbiology
- Specific Pathogen Groups
-
-
Question 2
Correct
-
A patient complains of headache and visual loss. CT scan demonstrates a lesion of the temporal lobe. What type of visual field defect would you most expect to see in this patient:
Your Answer: Contralateral homonymous superior quadrantanopia
Explanation:Axons from the lateral geniculate nucleus (LGN) carry visual information, via the upper and lower optic radiations, to the visual cortex in the occipital lobe:The upper optic radiation carries fibres from the superior retinal quadrants (corresponding to the inferior visual field quadrants) and travels through the parietal lobe to reach the visual cortex. The lower optic radiation carries fibres from the inferior retinal quadrants (corresponding to the superior visual field quadrants) and travels through the temporal lobe to reach the visual cortex of the occipital lobe.
-
This question is part of the following fields:
- Anatomy
- Central Nervous System
-
-
Question 3
Correct
-
You proceed to administer lorazepam intravenously to a 21-year-old patient with status epilepticus. Which of the following best describes lorazepam's action?
Your Answer: Potentiates effect of GABA
Explanation:Lorazepam is a type of benzodiazepine. Benzodiazepines are gamma-aminobutyric acid (GABA) receptor agonists with sedative, hypnotic, anxiolytic, anticonvulsant, and muscle relaxant characteristics that promote inhibitory synaptic transmission across the central nervous system.
-
This question is part of the following fields:
- Central Nervous System
- Pharmacology
-
-
Question 4
Correct
-
A man suffered from a back injury due to a fall from a ladder. Significant bruising was found to be overlying his latissimus dorsi muscle.Which of the following statements regarding the latissimus dorsi muscle is considered correct?
Your Answer: It raises the body towards the arm during climbing
Explanation:The latissimus dorsi muscle is a broad, flat muscle that occupies the majority of the lower posterior thorax. The muscle’s primary function is of the upper extremity but is also considered to be a respiratory accessory muscle.Latissimus dorsi is a climbing muscle. With the arms fixed above the head, it can raise the trunk upwards, together with the help of pectoralis major. Functionally, the latissimus dorsi muscle belongs to the muscles of the scapular motion. This muscle is able to pull the inferior angle of the scapula in various directions, producing movements on the shoulder joint (internal rotation, adduction and extension of the arm). It is innervated by the thoracodorsal nerve (C6 – C8) from the posterior cord of the brachial plexus, which enters the muscle on its deep surface.
-
This question is part of the following fields:
- Anatomy
- Upper Limb
-
-
Question 5
Incorrect
-
An analytical cohort study aimed to determine a relationship between intake of dietary calcium and incidence of hip fractures among post-menopausal women. The following are the data obtained from the study:No. of post-menopausal women who took Calcium: 500No. of post-menopausal women who took Calcium and suffered a hip fracture: 10No. of post-menopausal women who took placebo: 500No. of post-menopausal women who took placebo and suffered a hip fracture: 25Compute for the absolute risk reduction of a hip fracture.
Your Answer: 0.4
Correct Answer: 0.03
Explanation:Absolute risk reduction (ARR) is computed as the difference between the absolute risk in the control group (ARC) and the absolute risk in the treatment group (ART).ARR = ARC-ARTARR = (25/500) – (10/500)ARR = 0.03
-
This question is part of the following fields:
- Evidence Based Medicine
-
-
Question 6
Incorrect
-
Which of the following laboratory findings are suggestive of functional hyposplenism:
Your Answer: Rouleaux formation
Correct Answer: Howell-Jolly bodies
Explanation:Functional hyposplenism is characterised by the blood film findings of Howell-Jolly bodies or siderotic granules on iron staining. The most frequent cause is surgical removal of the spleen e.g. after traumatic rupture, but hyposplenism can also occur in sickle cell anaemia, gluten-induced enteropathy, amyloidosis and other conditions.
-
This question is part of the following fields:
- Immune Responses
- Pathology
-
-
Question 7
Correct
-
Antidiuretic hormone (ADH) levels are found to be increased in a young lady with unexplained hyponatraemia.In a healthy patient under normal circumstances, in which of the following conditions would ADH not be released?Â
Your Answer: Increased alcohol intake
Explanation:Antidiuretic hormone (ADH) is produced in the hypothalamus’s supraoptic nucleus and then released into the blood via axonal projections from the hypothalamus to the posterior pituitary.It is carried down axonal extensions from the hypothalamus (the neurohypophysial capillaries) to the posterior pituitary, where it is kept until it is released, after being synthesized in the hypothalamus.The secretion of ADH from the posterior pituitary is regulated by numerous mechanisms:Increased plasma osmolality: Osmoreceptors in the hypothalamus detect an increase in osmolality and trigger ADH release.Hypovolaemia causes a drop in atrial pressure, which stretch receptors in the atrial walls and big veins detect (cardiopulmonary baroreceptors). ADH release is generally inhibited by atrial receptor firing, but when the atrial receptors are stretched, the firing reduces and ADH release is promoted.Hypotension causes baroreceptor firing to diminish, resulting in increased sympathetic activity and ADH release.An increase in angiotensin II stimulates angiotensin II receptors in the hypothalamus, causing ADH production to increase.Nicotine, Sleep, Fright, and Exercise are some of the other elements that might cause ADH to be released.Alcohol (which partly explains the diuretic impact of alcohol) and elevated levels of ANP/BNP limit ADH release.
-
This question is part of the following fields:
- Physiology
- Renal Physiology
-
-
Question 8
Correct
-
Regarding cytotoxic T cells, which of the following statements is CORRECT:
Your Answer: They kill target cells by inducing cell apoptosis.
Explanation:CD8+ T-cells (Cytotoxic T cells)Recognise antigen only in association with HLA Class I molecules (found on all nucleated cells; present endogenous antigens such as those found in cells infected by viruses or intracellular bacteria.)Comprise about 25% of peripheral T-cellsResponsible for cytotoxic killing of target cells
-
This question is part of the following fields:
- Immune Responses
- Pathology
-
-
Question 9
Correct
-
A 20-year-old asthmatic patient's symptoms is deteriorating and patient is moved to the resuscitation area of the Emergency Department. A loading dose of IV aminophylline is administered and her symptoms begin to improve. You are asked to check her theophylline levels after an appropriate time period.How long should you wait before taking her blood sample be taken?
Your Answer: 4-6 hours
Explanation:Plasma theophylline concentration is usually measured five days after starting oral treatment and three days after each dose adjustment. A blood sample to check theophylline concentration should usually be taken after 4-6 hours if an IV dose of aminophylline was given.
-
This question is part of the following fields:
- Pharmacology
- Respiratory Pharmacology
-
-
Question 10
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 11
Correct
-
1-alpha-hydroxylase is a cytochrome p450 enzyme that is involved in the production of vitamin D's hormonally active metabolite.Which of the following promotes the activity of 1-alpha-hydroxylase?
Your Answer: Parathyroid hormone
Explanation:1-alpha-hydroxylase converts 25-hydroxycholecalciferol to 1,25-dihydroxycholecalciferol in the kidney.The key regulatory point in the formation of 1,25-dihydroxycholecalciferol is 1-alpha-hydroxylase, which is promoted by parathyroid hormone or hypophosphatemia.
-
This question is part of the following fields:
- Endocrine Physiology
- Physiology
-
-
Question 12
Correct
-
A 54-year-old woman presents with polyuria and polydipsia. She is known to suffer from bipolar disorder, which has been well controlled by the use of lithium for many years.What is the SINGLE most likely diagnosis?
Your Answer: Nephrogenic diabetes insipidus
Explanation:Diabetes insipidus is the inability to produce concentrated urine. It is characterised by the presence of excessive thirst, polyuria and polydipsia. There are two distinct types of diabetes insipidus:Cranial (central) diabetes insipidus and;Nephrogenic diabetes insipidusCranial diabetes insipidus is caused by a deficiency of vasopressin (anti-diuretic hormone). Patients with cranial diabetes insipidus can have a urine output as high as 10-15 litres per 24 hours, but adequate fluid intake allows most patients to maintain normonatraemia. 30% of cases are idiopathic, and a further 30% are secondary to head injuries. Other causes include neurosurgery, brain tumours, meningitis, granulomatous disease (e.g. sarcoidosis) and drugs, such as naloxone and phenytoin. A very rare inherited form also exists that is associated with diabetes mellitus, optic atrophy, nerve deafness and bladder atonia.Nephrogenic diabetes insipidus is caused by renal resistance to the action of vasopressin. As with cranial diabetes insipidus, urine output is markedly elevated. Serum sodium levels can be maintained by secondary polydipsia or can be elevated. Causes of nephrogenic diabetes insipidus include chronic renal disease, metabolic disorders (e.g. hypercalcaemia and hypokalaemia) and drugs, including long-term lithium usage and demeclocycline.In view of the history of long-term lithium use, in this case, nephrogenic diabetes insipidus is the most likely diagnosis.
-
This question is part of the following fields:
- Physiology
- Renal Physiology
-
-
Question 13
Incorrect
-
All of the following statements are considered true regarding likelihood ratios, except:
Your Answer: The likelihood ratio for a negative test = (1-sensitivity) / specificity
Correct Answer: If less than one, indicates that the information increases the likelihood of the suspected diagnosis
Explanation:The Likelihood Ratio (LR) is the likelihood that a given test result would be expected in a patient with the target disorder compared to the likelihood that that same result would be expected in a patient without the target disorder.The LR is used to assess how good a diagnostic test is and to help in selecting an appropriate diagnostic tests or sequence of tests. They have advantages over sensitivity and specificity because they are less likely to change with the prevalence of the disorder, they can be calculated for several levels of the symptom/sign or test, they can be used to combine the results of multiple diagnostic test and they can be used to calculate post-test probability for a target disorder.A LR greater than 1 produces a post-test probability which is higher than the pre-test probability. An LR less than 1 produces a post-test probability which is lower than the pre-test probability. When the pre-test probability lies between 30 and 70 per cent, test results with a very high LR (say, above 10) rule in disease. An LR below 1 produces a post-test probability les than the pre-test probability. A very low LR (say, below 0.1) virtually rules out the chance that the patient has the disease.
-
This question is part of the following fields:
- Evidence Based Medicine
-
-
Question 14
Correct
-
A 49-year-old man known sickle cell disease patient received a blood transfusion and developed a mild fever and dark urine 6 days after transfusion. His investigations show raised bilirubin, raised LDH, and a positive Direct Antiglobulin Test (DAT).Which transfusion reaction is most likely occurred?
Your Answer: Delayed haemolytic reaction
Explanation:Delayed haemolytic transfusion reactions (DHTRs) commonly occurs 4-8 days after blood transfusion, but can occur up to a month after. Signs and symptoms include jaundice, fever, an inadequate rise in PCV, reticulocytosis, a positive antibody screen and a positive Direct Antiglobulin Test (Coombs test). DHTRs usually have a benign course and require no treatment but sometimes, life-threatening haemolysis with severe anaemia and renal failure can occur so haemoglobin levels and renal function should be monitored.Acute haemolytic reaction aka immediate haemolytic transfusion reaction presents with fever, chills, pain at transfusion site, nausea, vomiting, dark urine and feeling of ‘impending doom’. Often, it occurs due to ABO incompatibility.Febrile transfusion reaction presents with a 1 degree rise in temperature from baseline during transfusion. Patient may have chills and malaise. It is the most common transfusion reaction (1 in 8 transfusions) and is usually caused by cytokines released from leukocytes in transfused red cell or platelet components.Transfusion-associated circulatory overload (TACO) presents as acute or worsening respiratory distress within 6 hours of transfusion of a large volume of blood. It is common in patients with diminished cardiac reserve or chronic anaemia. Elderly patients, infants and severely anaemic patients are particularly susceptible. Clinical features of TACO include: Acute respiratory distress, Tachycardia, Hypertension, Acute/worsening pulmonary oedema on chest X-ray. The BNP is usually raised to at least 1.5 times the pre-transfusion baseline.Graft versus host disease(GVHD) is an immune mediated condition that arises from a complex interaction between donor and recipients adaptive immunity. It presents as dermatitis, hepatitis and enteritis developing within 100 days after stem cell or bone marrow transplant.
-
This question is part of the following fields:
- Haematology
- Pathology
-
-
Question 15
Incorrect
-
Which of the following best characterizes the correct administration of amiodarone for a shockable rhythm in adults on advanced life support:
Your Answer: Give 300 mg IV amiodarone after 3 shocks, and then every 3 - 5 minutes thereafter
Correct Answer: Give 300 mg IV amiodarone after 3 shocks
Explanation:After three shocks, 300 mg IV amiodarone should be administered. After five defibrillation attempts, a further dose of 150 mg IV amiodarone may be considered. If amiodarone is not available, lidocaine may be used as a substitute, but it should not be given if amiodarone has previously been administered.
-
This question is part of the following fields:
- Cardiovascular
- Pharmacology
-
-
Question 16
Correct
-
Captopril should not be used if you have any of the following conditions:
Your Answer: Renal artery stenosis
Explanation:Contraindications indications of Captopril include:- Bilateral renal artery stenosis- Hypersensitivity to ACE inhibitors- Anuria- History of ACEI-induced angioedema- Hereditary or idiopathic angioedema- Co-administration of Neprilysin inhibitors (e.g., sacubitril) with ACE inhibitors may increase angioedema risk; do not administer ACE inhibitors within 36 hours of switching to or from sacubitril/valsartan.If ACE inhibitors are used, they should be initiated only under specialist supervision and renal function should be monitored regularly. ACE inhibitors should also be used with particular caution in patients who may have undiagnosed and clinically silent renovascular disease. This includes patients with peripheral vascular disease or those with severe generalised atherosclerosis.
-
This question is part of the following fields:
- Cardiovascular
- Pharmacology
-
-
Question 17
Incorrect
-
Question 18
Incorrect
-
An analytical study is conducted to compare the risk of stroke between Ticagrelor therapy and Warfarin therapy among patients with atrial fibrillation. The following is obtained from the study:No. of patients who took Ticagrelor: 300No. of patients who took Ticagrelor and suffered a stroke: 30No. of patients who took Warfarin: 500No. of patients who took Warfarin and suffered a stroke: 20Compute for the absolute risk reduction of a stroke, with Warfarin as the standard of treatment.
Your Answer: 0.04
Correct Answer: -0.06
Explanation:Absolute risk reduction (ARR) is computed as the difference between the absolute risk in the control group (ARC) and the absolute risk in the treatment group (ART).Since Warfarin is the standard of treatment, Warfarin is considered as the control group.ARR = ARC-ARTARR = (20/500) – (30/300)ARR = -0.06This means that there is increased risk of stroke in the treatment group, which is the Ticagrelor group.
-
This question is part of the following fields:
- Evidence Based Medicine
-
-
Question 19
Correct
-
Which one of these equations best defines lung compliance?
Your Answer: Change in volume / change in pressure
Explanation:Lung compliance is defined as change in volume per unit change in distending pressure. Lung compliance is calculated using the equation:Lung compliance = ΔV / ΔPWhere:ΔV is the change in volumeΔP is the change in pleural pressure.Static compliance is lung compliance in periods without gas flow, and is calculated using the equation:Static compliance = VT / Pplat − PEEPWhere:VT = tidal volumePplat = plateau pressurePEEP = positive end-expiratory pressure
-
This question is part of the following fields:
- Physiology
- Respiratory Physiology
-
-
Question 20
Correct
-
Which of the following nerves is most likely associated with an anterior shoulder dislocation?
Your Answer: Axillary nerve
Explanation:In an anterior dislocation, the arm is an abducted and externally rotated position. In the externally rotated position, the posterosuperior aspect of the humeral head abuts and drives through the anteroinferior aspect of the glenoid rim. This can damage the humeral head, glenoid labrum, or both. An associated humeral head compression fracture is described as a Hill Sach’s lesion. If large enough, it can lead to locked dislocations that may require open reduction. The glenoid labrum is a fibrocartilaginous structure that rings the circumference of the glenoid fossa. Bankart lesions are injuries to the anteroinferior glenoid labrum complex and the most common capsulolabral injury. A bony Bankart lesion refers to an associated fracture of the glenoid rim. These capsulolabral lesions are risk factors for recurrent dislocation.Axillary nerve injury is identified in about 42% of acute anterior shoulder dislocations. Nerve transection is rare, and traction injuries are more common. Arterial injury has also been described. The subclavian artery becomes the axillary artery after passing the first rib. The distal portion of the axillary artery is anatomically fixed and, therefore, susceptible to injury in anterior dislocations. Ischemic injury, including pseudoaneurysm and arterial laceration, is rare but carries marked morbidity if not quickly identified.
-
This question is part of the following fields:
- Anatomy
- Upper Limb
-
-
Question 21
Correct
-
A 43 year old lady who has a previous medical history of hyperthyroidism presents to the emergency room with sweating, palpitations and agitation. On examination, she is tachycardic, hypertensive and hyperpyrexic. She recently had a stomach bug and has not been able to take her medication regularly. The best medication to immediately treat her symptoms is which of the following?
Your Answer: Propranolol
Explanation:There is a high suspicion of a thyroid crisis in this patient and emergent treatment should be initiated even before the results of TFT’s have returned. Antiadrenergic drugs like IV propranolol should be administered immediately to minimise sympathomimetic symptoms. Antithyroid medications like propylthiouracil or carbimazole should be administered to block further synthesis of thyroid hormones. After thionamide therapy has been started to prevent stimulation of new hormone synthesis, there should then be delayed administration of oral iodine solution. Hydrocortisone administration is also recommended as it treats possible relative adrenal insufficiency while also decreases peripheral conversion of T4 to T3.
-
This question is part of the following fields:
- Endocrine
- Pharmacology
-
-
Question 22
Correct
-
Regarding the management of gout, which of the following statements is CORRECT:
Your Answer: Allopurinol may cause an acute attack of gout when first started.
Explanation:Allopurinol is a treatment for the prevention of gout. The initiation of treatment may precipitate an acute attack, and should be covered with an NSAID or colchicine, continued for at least one month after the hyperuricaemia has been corrected. Colchicine is not indicated for long term prevention of gout. NSAIDs are first line for acute gout; colchicine is an alternative in whom NSAIDs are contraindicated, not tolerated or ineffective (including in people taking anticoagulants). Ibuprofen is not recommended for acute gout, given it has only weak anti-inflammatory properties; naproxen, diclofenac or indometacin are indicated instead.
-
This question is part of the following fields:
- Musculoskeletal
- Pharmacology
-
-
Question 23
Correct
-
Which of the following drugs is first line treatment for a stable regular broad-complex tachycardia:
Your Answer: Amiodarone
Explanation:A regular broad-complex tachycardia is likely to be ventricular tachycardia or a regular supraventricular rhythm with bundle branch block. A ventricular tachycardia (or broad-complex tachycardia of uncertain origin) should be treated with amiodarone 300 mg IV over 10 – 60 min, followed by an infusion of 900 mg over the next 24 hours. If previously confirmed as SVT with bundle branch block, the patient should be treated as for narrow-complex tachycardia.
-
This question is part of the following fields:
- Cardiovascular
- Pharmacology
-
-
Question 24
Correct
-
Regarding hepatitis A, which of the following statements is CORRECT:
Your Answer: Anti-HAV IgM antibodies are diagnostic.
Explanation:Anti-HAV IgM antibodies are diagnostic. Disease in children is more commonly asymptomatic, risk of symptomatic disease increases with age. Transmission is by the faecal-oral route. Faecal shedding has been demonstrated for 2 – 3 weeks before and about a week after, the onset of jaundice. Infection confers lifelong immunity.
-
This question is part of the following fields:
- Microbiology
- Pathogens
-
-
Question 25
Correct
-
A 70-year-old patient presents with a chronic digoxin overdose. She has vomited several times, is extremely tired, and her vision 'appears yellow,' according to her.Which of the following is a reason for this patient's use of Digifab?
Your Answer: Coexistent renal failure
Explanation:An antidote for digoxin overdose is digoxin-specific antibody (Digifab). It’s a lyophilized preparation of digoxin-immune ovine Fab immunoglobulin fragments that’s sterile, purified, and lyophilized. These fragments were extracted from the blood of healthy sheep that had been immunised with a digoxin derivative called digoxin-dicarboxymethoxylamine (DDMA), a digoxin analogue that contains the functionally important cyclopentaperhydrophenanthrene:lactone ring moiety coupled to keyhole limpet hemocyanin (KLH).Digifab has a higher affinity for digoxin than digoxin does for its sodium pump receptor, which is thought to be the site of its therapeutic and toxic effects. When given to a patient who is intoxicated, Digifab binds to digoxin molecules, lowering free digoxin levels and shifting the equilibrium away from binding to receptors, reducing cardio-toxic effects. The kidney and reticuloendothelial system then clear the Fab-digoxin complexes.The following summarises the indications for Digifab in acute and chronic digoxin toxicity:Acute digoxin toxicityChronic digoxin toxicityCardiac arrestLife-threatening arrhythmiaPotassium level > 5 mmol/l>10 mg digoxin ingested (adult)>4 mg digoxin ingested (child)Digoxin level > 12 ng/mlCardiac arrestLife-threatening arrhythmiaSignificant gastrointestinal symptomsSymptoms of digoxin toxicity
-
This question is part of the following fields:
- Cardiovascular Pharmacology
- Pharmacology
-
-
Question 26
Correct
-
Regarding dermatophytes, which of the following statement is CORRECT:
Your Answer: Diagnosis is made from microscopy and culture of skin scrapings, hair samples or nail clippings.
Explanation:Diagnosis is made from microscopy and culture of skin scrapings, hair samples or nail clippings depending on the site of infection. The lesions of ringworm typically have a dark outer ring with a pale centre. Tinea capitis is ringworm affecting the head and scalp. Spread is via direct skin contact. Treatment is usually topical, oral antifungals are reserved for refractory infection.
-
This question is part of the following fields:
- Microbiology
- Pathogens
-
-
Question 27
Correct
-
The blood test reports of a 56-year-old female are sent for your review. She seems acutely sick and has had multiple infections over the past few months. Her complete blood count report shows neutropenia. Which one of the following options is true with regards to neutropenia?
Your Answer: It can be caused by both radiotherapy and chemotherapy
Explanation:A total neutrophil count of less than 2 x 109/L is defined as neutropenia. It can be caused by the following:1. viral infections2. SLE3. RA4. hypersplenism5. chemo- and radiotherapy6. vitamin B12 and folate deficiency7. drug reactions
-
This question is part of the following fields:
- Haematology
- Pathology
-
-
Question 28
Correct
-
Typically, granulomatous inflammation is associated with one of the following infections:
Your Answer: Tuberculosis
Explanation:Granulomatous inflammation is typically seen when an infective agent with a digestion-resistance capsule (e.g. Mycobacterium tuberculosis) or a piece of inert foreign material (such as suture or glass) is introduced into the tissue. A transient acute inflammatory response occurs and when this is ineffective in eradicating the stimulus, chronic inflammation occurs.Tuberculosis is the prototype of the granulomatous diseases, but sarcoidosis, cat-scratch disease, lymphogranuloma inguinale, leprosy, brucellosis, syphilis, some mycotic infections, berylliosis, reactions of irritant lipids, and some autoimmune diseases are also included
-
This question is part of the following fields:
- Inflammatory Responses
- Pathology
-
-
Question 29
Correct
-
EMLA cream is a topical local anaesthetic containing which of the following:
Your Answer: 50/50 mixture 2.5% lidocaine and 2.5% prilocaine
Explanation:EMLA cream, an effective topical local anaesthetic, is a 50/50 mixture of 2.5% prilocaine and 2.5% lidocaine.
-
This question is part of the following fields:
- Anaesthesia
- Pharmacology
-
-
Question 30
Incorrect
-
Which of the following is NOT an indication for a H1 receptor antihistamine:
Your Answer: Anaphylaxis
Correct Answer: Gastroesophageal reflux disease
Explanation:Antihistamines are competitive inhibitors at the H1-receptor (in contrast to H2 receptor antagonists used to decrease gastric acid secretion in gastroesophageal reflux disease).Indications: Allergic rhinitis and conjunctivitisUrticarial rashes, pruritus, insect bites and stingsAngioedemaAnaphylaxis (second line adjunct to adrenaline)Nausea/vomiting and prevention of motion sicknessInsomnia
-
This question is part of the following fields:
- Pharmacology
- Respiratory
-
-
Question 31
Correct
-
Regarding the phases of gastric secretion, which of the following statements is INCORRECT:
Your Answer: A high pH in the stomach inhibits gastrin secretion.
Explanation:A low pH in the stomach inhibits gastrin secretion, therefore when the stomach is empty or when acid has been secreted for some time after food has entered it, there is inhibition of acid secretion. However, when food first enters the stomach, the pH rises, and this leads to release of the inhibition and causes a maximum secretion of gastrin. Thus gastric acid secretion is self-regulating.
-
This question is part of the following fields:
- Gastrointestinal
- Physiology
-
-
Question 32
Correct
-
Regarding acute lymphoblastic leukaemia (ALL), which of the following statements is CORRECT:
Your Answer: ALL is the most common malignancy of childhood.
Explanation:Acute lymphoblastic leukaemia (ALL) is caused by an accumulation of lymphoblasts in the bone marrow and is the most common malignancy of childhood. The incidence of ALL is highest at 3 – 7 years, with 75% of cases occurring before the age of 6. 85% of cases are of B-cell lineage. Haematological investigations reveal a normochromic normocytic anaemia with thrombocytopenia in most cases. The total white cell count may be decreased, normal or increased. The blood film typically shows a variable number of blast cells. The bone marrow is hypercellular with >20% blast cells.
-
This question is part of the following fields:
- Haematology
- Pathology
-
-
Question 33
Correct
-
Flucloxacillin is used first line for all of the following infections EXCEPT for:
Your Answer: Otitis media
Explanation:Flucloxacillin is used first line for treatment of widespread impetigo infection, cellulitis, mastitis, osteomyelitis, septic arthritis, severe erysipelas, severe/spreading otitis externa and infective endocarditis caused by staphylococci. Amoxicillin is first line for acute otitis media.
-
This question is part of the following fields:
- Infections
- Pharmacology
-
-
Question 34
Incorrect
-
Which of the following pathogens is most likely to cause an infection in a chemo patient with significant neutropenia?
Your Answer: Haemophilus influenzae
Correct Answer: Candida
Explanation:Chemotherapy that is too aggressive weakens your immune system, putting you at risk for a fungal and many other infection. Neutropenia is a condition in which a person’s neutrophil count is abnormally low. Neutrophils are an infection-fighting type of white blood cell. Neutrophils fight infection by killing bacteria and fungi (yeast) that infiltrate the body. Fungal organisms are significant pathogens in the setting of neutropenia.
-
This question is part of the following fields:
- Immune Responses
- Pathology
-
-
Question 35
Correct
-
Which of the following is true about the extensor carpi radialis longus?
Your Answer: It assists with abduction of the hand at the wrist
Explanation:The majority of extensor carpi radialis longus originates from the lateral supracondylar ridge of humerus (distal third) and anterior aspect of the lateral intermuscular septum of the arm. A small portion of its fibres originate from the common extensor tendon attached to the lateral epicondyle of humerus. The fibres unite into a muscle belly which extends approximately to the middle of the forearm. The muscle belly is then replaced by a flat tendon that travels distally along the lateral surface of the radius, together with the tendon of extensor carpi radialis brevis. Both tendons course towards the radial styloid process, deep to the tendons of abductor pollicis longus and extensor pollicis brevis muscles. Proximal to the wrist, the tendons of extensor carpi radialis longus and brevis pass behind the radial styloid process within a common synovial sheath and continue along the radial groove deep to the extensor retinaculum of the wrist. At this level, the tendon of extensor carpi radialis longus is crossed by the tendon of extensor pollicis longus, after which it inserts on the posterior aspect of the base of the second metacarpal bone. Some tendon slips can insert into the first and third metacarpal bones.Extensor carpi radialis longus receives innervation from the radial nerve, with contributions mainly from spinal nerves C5-C8. The radial nerve is a branch of the brachial plexus.Extensor carpi radialis longus receives blood supply mainly from the radial artery. It directly supplies the distal part of the muscle, while the rest of the muscle receives blood from one of its radial recurrent branches. The brachial artery also supplies a small portion of the muscle via the radial collateral artery.Extensor carpi radialis longus primarily acts on the wrist joint to produce two major actions: (1) wrist extension by working synergistically with extensor carpi radialis brevis and extensor carpi ulnaris, and (2) hand abduction (radial deviation), with the help of flexor carpi radialis.
-
This question is part of the following fields:
- Anatomy
- Upper Limb
-
-
Question 36
Correct
-
A 13-year-old male presents to the Emergency Department with a heavy nosebleed. His medical record shows that he was diagnosed with Haemophilia B as a child. What is the mode of inheritance of this disease?
Your Answer: X-linked recessive
Explanation:Deficiency of Factor IX causes Haemophilia B, and like the other Haemophilia’s, it has an X-linked recessive pattern of inheritance, affecting males born to carrier mothers.Haemophilia B is the second commonest form of haemophilia and is rarer than haemophilia A. Haemophilia B is similar to haemophilia A but is less severe. You can distinguish the two disorders by specific coagulation factor assays. The incidence of Haemophilia B is one-fifth of that of haemophilia A. In laboratory findings, you get prolonged APTT, normal PT and low factor IX for Haemophilia B. There is also a variation called Leyden, in which factor IX levels are below 1% until puberty, when they rise, potentially reaching as high as 40-60% of normal. This is thought to be due to the effects of testosterone at puberty.
-
This question is part of the following fields:
- Haematology
- Pathology
-
-
Question 37
Incorrect
-
A 35-year-old man presents with haemoptysis, night sweats, and weight loss. Further examinations were done and a diagnosis of tuberculosis is suspected. Which of the following statements is considered correct regarding Mycobacterium tuberculosis?
Your Answer: It Gram stains red
Correct Answer: It is impervious to decolourisation with acid
Explanation:Mycobacterium tuberculosis are part of the Mycobacteriaceae family. They are described to have the characteristics of a Gram-positive cell wall but they are not easily stained with Gram stain. This is because their cell wall contains a high lipid content, and this lipid allows the Mycobacteria to bind to alkaline stains with the application and help of heat. Once stained, they are able to resist decolorization even with the use of acid alcohol as the decolourizer, making them very difficult to decolorize, that is why they are known to be acid-fast.The Ghon complex is a non-pathognomonic radiographic finding on a chest x-ray that is significant for pulmonary infection of tuberculosis. The location of the Ghon’s focus is usually subpleural and predominantly in the upper part of the lower lobe and lower part of the middle or upper lobe. Skeletal tuberculosis of the spine is referred to as Pott disease.The risk of reactivation TB is about 3.3% during the first year after a positive PPD skin test and a total of 5% to 15% thereafter in the person’s lifetime. Progression from infection to active disease varies with age and the intensity and duration of exposure. Reactivation TB occurs when there is an alteration or suppression of the cellular immune system in the infected host that favoursreplication of the bacilli and progression to disease.
-
This question is part of the following fields:
- Microbiology
- Specific Pathogen Groups
-
-
Question 38
Correct
-
All of the following statements regarding Helicobacter pylori is considered true, except:
Your Answer: Serum antibody levels should be used to check for successful eradication
Explanation:Helicobacter pylori is a curved, non-spore forming, Gram-negative bacteria that is primarily linked to gastric infections. Once acquired, it colonizes the stomach for a long time and can cause a low-grade inflammatory process, producing a chronic superficial gastritis.H. pylori can be recovered from gastric biopsy materials. Samples must be transported quickly to the laboratory.Helicobacter infections usually are identified by nonculture methods. H. pylori can be presumptively identified in a gastric biopsy specimen by testing for the presence of a rapid urease reaction.Serologic testing is an important screening method for the diagnosis of H. pylori infection. It can also be diagnosed by faecal antigen detection, microscopic examination of stained gastric tissue, and DNA amplification tests.
-
This question is part of the following fields:
- Microbiology
- Specific Pathogen Groups
-
-
Question 39
Incorrect
-
Regarding fibrinolytics, which of the following statements is INCORRECT:
Your Answer: Tenecteplase has a longer half-life than alteplase allowing for bolus administration.
Correct Answer: Fibrinolytic drugs act as thrombolytics by directly degrading the fibrin mesh and so breaking up thrombi.
Explanation:Fibrinolytic drugs act as thrombolytics by activating plasminogen to form plasmin, which degrades fibrin and so breaks up thrombi.
-
This question is part of the following fields:
- Cardiovascular
- Pharmacology
-
-
Question 40
Correct
-
A 30-year old male is brought to the emergency room after a terrible fall during a photoshoot. The patient reported falling on his right forearm. There is evident swelling and tenderness on the affected area, with notable weakness of the flexor pollicis longus muscle. Radiographic imaging showed a fracture on the midshaft of the right radius.Which of the following nerves is most likely injured in the case above?
Your Answer: The anterior interosseous nerve
Explanation:Flexor pollicis longus receives nervous supply from the anterior interosseous branch of median nerve, derived from spinal roots C7 and C8.
-
This question is part of the following fields:
- Anatomy
- Upper Limb
-
-
Question 41
Correct
-
The pathophysiology of Addison's disease is as follows:
Your Answer: Adrenocortical insufficiency
Explanation:Primary adrenal insufficiency, also known as Addison’s disease, occurs when the adrenal glands cannot produce an adequate amount of hormones despite a normal or increased corticotropin (ACTH) level.
-
This question is part of the following fields:
- Endocrine
- Physiology
-
-
Question 42
Correct
-
Which of the following nerves supply the superficial head of the flexor pollicis brevis muscle?
Your Answer: The recurrent branch of the median nerve
Explanation:The two heads of the flexor pollicis brevis usually differ in their innervation. The superficial head of flexor pollicis muscle receives nervous supply from the recurrent branch of the median nerve, whereas the deep head receives innervation from the deep branch of the ulnar nerve, derived from spinal roots C8 and T1.
-
This question is part of the following fields:
- Anatomy
- Upper Limb
-
-
Question 43
Correct
-
Regarding the resting membrane potential, which of the following statements is CORRECT:
Your Answer: The resting cell membrane is more permeable to K + ions than to Na + ions.
Explanation:A membrane potential is a property of all cell membranes, but the ability to generate an action potential is only a property of excitable tissues. The resting membrane is more permeable to K+and Cl-than to other ions (and relatively impermeable to Na+); therefore the resting membrane potential is primarily determined by the K+equilibrium potential. At rest the inside of the cell is negative relative to the outside. In most neurones the resting potential has a value of approximately -70 mV.
-
This question is part of the following fields:
- Basic Cellular
- Physiology
-
-
Question 44
Correct
-
A 29-year-old volunteer returns from a recent trip to the middle east with profuse watery diarrhoea. You make a diagnosis of cholera and organize a hospital admission for rehydration with intravenous fluids.What is the mechanism of action of cholera toxin?
Your Answer: ADP-ribosylation of the G regulatory protein
Explanation:Cholera is caused by Vibrio cholerae, a motile, Gram-negative, curved bacillus. It is transmitted through water and food (especially seafood) and is primarily a disease seen in developing countries where there is poor sanitation and lack of safe water supplies.The cholera toxin leads to stimulation of adenyl cyclase, ADP-ribosylation of the G regulatory protein, inactivation of GTPase leading to active outpouring of NaCl. The cholera toxin consists of an A (the toxin) and B subunit. The B subunit attaches to the gut mucosa and presents the A subunit to the cell. The toxin stimulates adenyl cyclase by irreversible ADP-ribosylation of the GTP binding domain of adenyl cyclase leading to the opening of chloride channels resulting in an outpouring of NaCl and water into the lumen of the gut and causing secretory diarrhoea.Incubation period is between 2 and 5 days, but can be as short as just a few hours.
-
This question is part of the following fields:
- Microbiology
- Principles Of Microbiology
-
-
Question 45
Incorrect
-
Which of the following nerves is most important for eversion of the foot:
Your Answer: Deep fibular nerve
Correct Answer: Superficial fibular nerve
Explanation:Eversion of the foot is primarily produced by the fibularis longus and fibularis brevis, both innervated by the superficial fibular nerve. The fibularis tertius, innervated by the deep fibular nerve, also assists in this action.
-
This question is part of the following fields:
- Anatomy
- Lower Limb
-
-
Question 46
Correct
-
A 44 year old woman sustains an injury to the median nerve at the elbow after falling awkwardly. Which of the following clinical features are you LEAST likely to see on examination:
Your Answer: Loss of flexion of the medial two digits
Explanation:Flexion of the index and middle fingers at the IPJs is lost due to paralysis of the flexor digitorum superficialis and the lateral half of the flexor digitorum profundus. Flexion of the MCPJs of the index and middle fingers are lost due to paralysis of the lateral two lumbrical muscles. Flexion of the ring and little fingers are preserved as these are supported by the medial half of the flexor digitorum profundus and the medial two lumbrical muscles, innervated by the ulnar nerve.
-
This question is part of the following fields:
- Anatomy
- Upper Limb
-
-
Question 47
Incorrect
-
One of your patients is in resuscitation and is suffering from kidney failure. The intensive care outreach team arrives to assess them and determines that a dopamine infusion is necessary.Dopamine primarily acts on which of the following receptors at low doses?
Your Answer: Alpha-1 receptors
Correct Answer: Dopamine receptors
Explanation:Dopamine is a catecholamine that occurs naturally and is used to treat low cardiac output, septic shock, and renal failure. It is both adrenaline and noradrenaline’s immediate precursor.Dopamine acts on D1 and D2 dopamine receptors in the renal, mesenteric, and coronary beds at low doses (1-5 g/kg/min). Dopamine causes a significant decrease in renal vascular resistance and an increase in renal blood flow at these doses. Within this dose range, it is also involved in central modulation of behaviour and movement.Dopamine stimulates beta- and alpha-adrenergic receptors directly and indirectly at higher doses. Beta-stimulation predominates at a rate of 5-10 g/kg/min, resulting in a positive inotropic effect that increases cardiac output and coronary blood flow. Alpha-stimulation predominates at infusion rates greater than 15 g/kg/min, resulting in peripheral vasoconstriction and an increase in venous return and systolic blood pressure.Below is a summary of the mechanisms and effects of various inotropic agents:InotropeMechanismEffectsAdrenaline (epinephrine)Beta-1 and -2 agonist at increasing doses;Alpha-agonist at high dosesIncreased cardiac output;Vasoconstriction at higher dosesNoradrenaline (norepinephrine)Mainly alpha-agonist;Beta-1 and -2 agonist at increasing dosesVasoconstriction;Some increased cardiac outputDopamineDopamine agonist at low doses;Beta-1 and -2 agonist at increasing doses;Alpha-agonist at high dosesIncreased cardiac output;Vasoconstriction at higher dosesDobutamineMainly beta-1 agonistIncreased cardiac output
-
This question is part of the following fields:
- Cardiovascular Pharmacology
- Pharmacology
-
-
Question 48
Correct
-
A 72-year-old man presents with chest pain that is characteristic of angina. You administer a dose of glyceryl trinitrate (GTN), which rapidly resolved his symptoms. Unfortunately, he also develops an unpleasant side effect.Which of the following side effects is he most likely to have developed? Select ONE answer only.
Your Answer: Headache
Explanation:Nitrates are used in the treatment of angina pectoris and the prevention of myocardial ischaemia. Commonly used examples of nitrates are glyceryl trinitrate and isosorbide dinitrate. Unwanted effects, however, are common and can limit therapy, particularly when angina is severe or when patients are unusually sensitive to the effects of nitrates.The following are common or very common side effects of nitratesArrhythmiasAstheniaCerebral ischaemiaDizzinessDrowsinessFlushingHeadacheHypotensionNausea and vomitingDiarrhoea, syncope and cyanosis can occur, but these are rare side effects. Dry eyes, bradycardia and metabolic acidosis have not been reported.
-
This question is part of the following fields:
- Cardiovascular Pharmacology
- Pharmacology
-
-
Question 49
Correct
-
Which of the following clinical features is a feature of a chronic extravascular haemolytic anaemia:
Your Answer: Gallstones
Explanation:Clinical features of haemolytic anaemia include:AnaemiaJaundice (caused by unconjugated bilirubin in plasma, bilirubin is absent from urine)Pigment gallstonesSplenomegalyAnkle ulcersExpansion of marrow with, in children, bone expansion e.g. frontal bossing in beta-thalassaemia majorAplastic crisis caused by parvovirus
-
This question is part of the following fields:
- Haematology
- Pathology
-
-
Question 50
Incorrect
-
The lymph drainage of the anal canal above the pectinate line is initially to the:
Your Answer: Superficial inguinal nodes
Correct Answer: Internal iliac nodes
Explanation:Above the pectinate line, the anal canal drains to the internal iliac lymph nodes which subsequently drain to the lumbar (para-aortic) nodes.
-
This question is part of the following fields:
- Abdomen
- Anatomy
-
SESSION STATS - PERFORMANCE PER SPECIALTY
