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Question 1
Incorrect
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Regarding Escherichia coli, which of the following statements is INCORRECT:
Your Answer: It is a common cause of neonatal meningitis.
Correct Answer: It is a predominant member of the normal flora of the skin.
Explanation:Escherichia coli is a Gram-negative bacilli that is an important member of the intestinal flora. It is the most common cause of UTI in adults (about 70 – 95% of cases), followed by Staphylococcus saprophyticus (about 5 – 10% of cases), and an important cause of neonatal meningitis. E. coli O157 strain is implicated in the development of dysentery associated with haemolytic uraemic syndrome characterised by haemolytic anaemia, thrombocytopenia and acute renal failure.
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This question is part of the following fields:
- Microbiology
- Pathogens
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Question 2
Correct
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The most common cause of anaemia worldwide is which of the following?
Your Answer: Iron deficiency anaemia
Explanation:The most common cause of microcytic anaemia and of any anaemia worldwide is iron deficiency anaemia.
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This question is part of the following fields:
- Haematology
- Pathology
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Question 3
Correct
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A young patient presents with the features of an easily recognisable infectious disease.Which of the following infectious diseases typically has an incubation period of less than 1 week? Select ONE answer only.
Your Answer: Cholera
Explanation:Cholera has an incubation period of 12 hours to 6 days.Other infectious disease that have an incubation period of less than 1 week include:Staphylococcal enteritis (1-6 hours)Salmonella enteritis (12-24 hours)Botulism (18-36 hours)Gas gangrene (6 hours to 4 days)Scarlet fever (1-4 days)Diphtheria (2-5 days)Gonorrhoea (3-5 days)Yellow fever (3-6 days)Meningococcaemia (1-7 days)Brucellosis has an incubation period of 7-21 days.Measles has an incubation period of 14-18 days.Falciparum malaria usually has an incubation period of 7-14 days. The other forms of malaria have a longer incubation period of 12-40 days.Rubella has an incubation period of 14-21 days.
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This question is part of the following fields:
- Microbiology
- Specific Pathogen Groups
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Question 4
Correct
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A 50-year-old man presents with headaches, lethargy, hypertension, and electrolyte disturbance. A diagnosis of primary hyperaldosteronism is made.Which biochemical pictures would best support this diagnosis?
Your Answer: Hypokalaemic metabolic alkalosis
Explanation:When there are excessive levels of aldosterone outside of the renin-angiotensin axis, primary hyperaldosteronism occurs. High renin levels will lead to secondary hyperaldosteronism. The classical presentation of hyperaldosteronism when symptoms are present include:HypokalaemiaMetabolic alkalosisHypertensionNormal or slightly raised sodium levels
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This question is part of the following fields:
- Endocrine Physiology
- Physiology
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Question 5
Incorrect
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For a tachyarrhythmia caused by shock, which of the following is the first-line treatment:
Your Answer: Intravenous magnesium
Correct Answer: Synchronised DC shock
Explanation:If there are any adverse symptoms, immediate cardioversion with synchronized DC shock is recommended. If cardioversion fails to stop the arrhythmia and the symptoms persist, amiodarone 300 mg IV over 10–20 minutes should be administered before attempting another cardioversion. The loading dosage of amiodarone is followed by a 24-hour infusion of 900 mg administered into a large vein.
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This question is part of the following fields:
- Cardiovascular
- Pharmacology
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Question 6
Incorrect
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A patient has an elevated potassium level of 6.7 mmol/L. All of the following conditions may cause elevated potassium levels, except for which one?
Your Answer: Beta-blockers
Correct Answer: Bartter’s syndrome
Explanation:Bartter’s syndrome is an autosomal recessive renal tubular disorder characterized by hypokalaemia, hypochloraemia, metabolic alkalosis, and hyperreninemia with normal blood pressure. The underlying kidney abnormality results in excessive urinary losses of sodium, chloride, and potassium. Bartter’s syndrome does not cause an elevated potassium level, but instead causes a decrease in its concentration (hypokalaemia). The other choices are causes of hyperkalaemia or elevated potassium levels. Renal failure, Addison’s disease (adrenal insufficiency), congenital adrenal hyperplasia, renal tubular acidosis (type 4), rhabdomyolysis, burns and trauma, tumour syndrome, and acidosis are non-drug causes of hyperkalaemia. On the other hand, drugs that can cause hyperkalaemia include ACE inhibitors, angiotensin receptor blockers, NSAIDs, beta-blockers, digoxin, and suxamethonium.
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This question is part of the following fields:
- Physiology
- Renal Physiology
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Question 7
Incorrect
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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: Weakness of pronation
Correct 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.
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This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 8
Correct
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You are reviewing a patient complaining of loss of vision. Previous images shows a lesion at the optic chiasm. What type of visual field defect are you most likely to see in a lesion at the optic chiasm:
Your Answer: Bitemporal hemianopia
Explanation:A lesion at the optic chiasm will result in a bitemporal hemianopia.A lesion of the optic nerve will result in ipsilateral monocular visual loss.A lesion of the optic tract will result in a contralateral homonymous hemianopia.
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This question is part of the following fields:
- Anatomy
- Central Nervous System
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Question 9
Incorrect
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A 30-year-old patient has a mild exacerbation of his asthma. His steroid inhaler ran out a couple of weeks ago, and he has not replaced it.Which of these statements describes the mechanism of action of corticosteroids in asthma?
Your Answer: Smooth muscle relaxation
Correct Answer: Reduction of bronchial inflammation
Explanation:Inhaled corticosteroids suppresses airway inflammation seen in asthma by downregulating pro-inflammatory proteins.They also appear to reverse components of asthma-induced structural changes (airway remodelling), including increased vascularity of the bronchial wall.Corticosteroids reduces the number of inflammatory cells (eosinophils, T lymphocytes, mast cells, and dendritic cells) in the airways.
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This question is part of the following fields:
- Pharmacology
- Respiratory Pharmacology
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Question 10
Correct
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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.
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This question is part of the following fields:
- Basic Cellular
- Physiology
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Question 11
Incorrect
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Salbutamol should be used with caution in patients with which of the following:
Your Answer: Gout
Correct Answer: Susceptibility to QT-interval prolongation
Explanation:Beta-2 agonists should be used with caution in people with: Cardiovascular disease, including arrhythmias and hypertension (beta-2 agonists may cause an increased risk of arrhythmias and significant changes to blood pressure and heart rate)Diabetes(risk of hyperglycaemia and ketoacidosis, especially with intravenous use)Hyperthyroidism(beta-2 agonists may stimulate thyroid activity)Hypokalaemia(potentially serious hypokalaemia may result from beta-2 agonist therapy; this effect may be potentiated in severe asthma by concomitant treatment with theophylline, corticosteroids, diuretics and by hypoxia)Susceptibility to QT-interval prolongationConvulsive disorders
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This question is part of the following fields:
- Pharmacology
- Respiratory
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Question 12
Correct
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You've been summoned to your Emergency Department resuscitation area to see a patient. You consider giving him an atropine shot because he is severely bradycardic.Which of the following statements about the use of atropine is correct?
Your Answer: It blocks the effects of the vagus nerve on both the SA and AV nodes
Explanation:At muscarinic receptors, atropine blocks the action of the parasympathetic neurotransmitter acetylcholine. As a result, it inhibits the vagus nerve’s effects on both the SA and AV nodes, increasing sinus automaticity and facilitating AV node conduction.At muscarinic receptors, atropine blocks the action of the parasympathetic neurotransmitter acetylcholine. As a result, it inhibits the vagus nerve’s effects on both the SA and AV nodes, increasing sinus automaticity and facilitating AV node conduction.The most common cause of asystole during cardiac arrest is primary myocardial pathology, not excessive vagal tone, and there is no evidence that atropine is helpful in the treatment of asystole or PEA. As a result, it is no longer included in the ALS algorithm’s non-shockable section. Atropine is most commonly used in the peri-arrest period. It is used to treat bradycardia (sinus, atrial, or nodal) or AV block when the patient’s haemodynamic condition is compromised by the bradycardia.If any of the following adverse features are present, the ALS bradycardia algorithm recommends a dose of 500 mcg IV:ShockSyncopeMyocardial ischaemiaHeart failureAtropine is also used for the following purposes:Topically as a cycloplegic and mydriatic to the eyesTo cut down on secretions (e.g. in anaesthesia)Organophosphate poisoning is treated withAtropine’s side effects are dose-dependent and include:Mouth is parchedVomiting and nauseaVision is hazyRetention of urineTachyarrhythmiasIt can also cause severe confusion and hallucinations in patients, especially the elderly.
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This question is part of the following fields:
- Cardiovascular Pharmacology
- Pharmacology
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Question 13
Incorrect
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Regarding fat digestion, which of the following statements is CORRECT:
Your Answer: Fat in the diet is mainly in the form of cholesterol.
Correct Answer: Chylomicrons consist of a cholesterol and triglyceride core with a phospholipid coat studded with apolipoproteins.
Explanation:Dietary fat is chiefly composed of triglycerides. In the duodenum fat is emulsified by bile acids, a process where larger lipid droplets are broken down into much smaller droplets providing a greater surface area for enzymatic digestion. Once inside the epithelial cell, lipid is taken into the smooth endoplasmic reticulum where much of it is re esterified. Dietary and synthesised lipids are then incorporated into chylomicrons in the Golgi body, which are exocytosed from the basolateral membrane to enter lacteals. Chylomicrons consist mainly of triglyceride with small amounts of cholesterol and cholesteryl esters in the centre with a phospholipid coat studded with apolipoproteins. Fat-soluble are absorbed into enterocytes from micelles by simple diffusion together with the products of fat digestion.
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This question is part of the following fields:
- Gastrointestinal
- Physiology
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Question 14
Incorrect
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Which of the following is the most potent stimulus of fibrinolysis:
Your Answer: Antithrombin
Correct Answer: Tissue plasminogen activator
Explanation:Fibrinolysis is a normal haemostatic response to vascular injury. Plasminogen, a proenzyme in blood and tissue fluid, is converted to plasmin by activators either from the vessel wall (intrinsic activation) or from the tissues (extrinsic activation). The most important route follows the release of tissue plasminogen activator (TPA) from endothelial cells.
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This question is part of the following fields:
- Basic Cellular
- Physiology
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Question 15
Incorrect
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All of the following statements are considered true regarding randomized control trials, except:
Your Answer: They can overcome small sample sizes
Correct Answer: They can eliminate the need for further studies
Explanation:Meta-analysis is a quantitative, formal, epidemiological study design used to systematically assess previous research studies to derive conclusions about that body of research. Outcomes from a meta-analysis may include a more precise estimate of the effect of treatment or risk factor for disease, or other outcomes, than any individual study contributing to the pooled analysis. The examination of variability or heterogeneity in study results is also a critical outcome.The benefits of meta-analysis include a consolidated and quantitative review of a large, and often complex, sometimes apparently conflicting, body of literature. The specification of the outcome and hypotheses that are tested is critical to the conduct of meta-analyses, as is a sensitive literature search.Important medical questions are typically studied more than once, often by different research teams in different locations. In many instances, the results of these multiple small studies of an issue are diverse and conflicting, which makes the clinical decision-making difficult. The need to arrive at decisions affecting clinical practise fostered the momentum toward evidence-based medicine. Evidence-based medicine may be defined as the systematic, quantitative, preferentially experimental approach to obtaining and using medical information. Therefore, meta-analysis, a statistical procedure that integrates the results of several independent studies, plays a central role in evidence-based medicine.
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This question is part of the following fields:
- Evidence Based Medicine
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Question 16
Incorrect
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An unrelated medical condition brings a 28-year-old asthmatic man to the Emergency Department. When you look over his meds, you notice that he is taking Theophylline to help with his asthma.Which of the following medicines should you NOT prescribe?
Your Answer: Paracetamol
Correct Answer: Ciprofloxacin
Explanation:Ciprofloxacin is a cytochrome P450 enzyme inhibitor that raises theophylline levels in the blood. As a result, co-prescribing theophylline should be avoided.The medicines that typically impact theophylline’s half-life and plasma concentration are listed in the table below:Drugs that increase the levels of theophylline in the bloodDrugs that lower theophylline levels in the bloodCalcium channel blockers e.g. VerapamilFluconazoleCimetidineQuinolones, e.g. ciprofloxacinMethotrexateBarbituratesCarbamazepinePhenobarbitalMacrolides, e.g. erythromycinPhenytoin (and fosphenytoin)RifampicinSt. John’s wort
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This question is part of the following fields:
- Pharmacology
- Respiratory Pharmacology
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Question 17
Correct
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You review a sick patient in resus who has been prescribed mannitol as part of his treatment protocol.Which SINGLE statement regarding mannitol is true?
Your Answer: It is irritant to veins and causes phlebitis
Explanation:Mannitol is a low molecular weight compound and is therefore freely filtered at the glomerulus and is not reabsorbed. It, therefore, increases the osmolality of the glomerular filtrate and tubular fluid, increasing urinary volume by an osmotic effect. It also does not cross the blood-brain barrier (BBB).Mannitol is primarily used to reduce the pressure and volume of cerebrospinal fluid (CSF). It decreases the volume of CSF by:Decreasing the rate of CSF formation,and;Withdrawing extracellular fluid from the brain across the BBBOther uses of mannitol include:Short-term management of glaucomaTreatment of rhabdomyolysisPreserve renal function in peri-operative jaundiced patientsTo initiate diuresis in transplanted kidneysBowel preparation prior to colorectal proceduresThe recommended dose of mannitol for the reduction of CSF pressure/cerebral oedema is 0.25-2g/kg as an intravenous infusion over 30-60 minutes. This can be repeated 1-2 times after 4-8 hours if needed.Circulatory overload and rebound increases in intracranial pressure may occur following the use of mannitol. It is irritant to tissues and veins and can cause inflammation and phlebitis.Mannitol causes an expansion of the extracellular fluid space, which may worsen congestive cardiac failure. Contraindications to the use of mannitol include:AnuriaIntracranial bleeding (except during craniotomy)Severe cardiac failureSevere dehydrationSevere pulmonary oedema
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This question is part of the following fields:
- Cardiovascular Pharmacology
- Pharmacology
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Question 18
Correct
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Which of the following factors decreases insulin secretion:
Your Answer: Catecholamines
Explanation:Factors that increase insulin secretion:↑ Blood glucose↑ Amino acids↑ Fatty acidsGlucagonSecretinAcetylcholineFactors that decrease insulin secretion:↓ Blood glucoseSomatostatinCatecholamines
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This question is part of the following fields:
- Endocrine
- Physiology
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Question 19
Incorrect
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A 23-year-old student presents with a fever and sore throat. Upon physical examination, it was observed that he had bilaterally enlarged tonsils that are covered in large amounts of exudate. A diagnosis of tonsillitis was made. The lymph from the tonsils will drain to which of the following nodes?
Your Answer: Posterior auricular lymph nodes
Correct Answer: Deep cervical lymph nodes
Explanation:The tonsils are collections of lymphatic tissue located within the pharynx. They collectively form a ringed arrangement, known as Waldeyer’s ring: pharyngeal tonsil, 2 tubal tonsils, 2 palatine tonsils, and the lingual tonsil. Lymphatic fluid from the lingual tonsil drains into the jugulodigastric and deep cervical lymph nodes.Lymphatic fluid from the pharyngeal tonsil drains into the retropharyngeal nodes (which empty into the deep cervical chain), and directly into deep cervical nodes within the parapharyngeal space.The retropharyngeal and the deep cervical lymph nodes drain the tubal tonsils.The palatine tonsils drain to the jugulodigastric node, a node of the deep cervical lymph nodes, located inferior to the angle of the mandible.
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This question is part of the following fields:
- Anatomy
- Head And Neck
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Question 20
Incorrect
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Regarding the flexor digitorum profundus muscle, which of the following is true?
Your Answer: The entire muscle is innervated by the ulnar nerve
Correct Answer: The medial aspect of the muscle is innervated by the ulnar nerve
Explanation:Flexor digitorum profundus is a fusiform muscle located deep within the anterior (flexor) compartment of the forearm. Along with the flexor pollicis longus and pronator quadratus muscles, it comprises the deep flexor compartment of the forearm.Flexor digitorum profundus has a dual innervation:(1) The medial part of the muscle, that inserts to the fourth and fifth digits, is innervated by the ulnar nerve (C8-T1);(2) The lateral part, that inserts to the second and third digits, is innervated by the median nerve, via anterior interosseous branch (C8-T1).
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This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 21
Incorrect
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Which of the following movements is controlled by the pectoralis major muscle?
Your Answer: Extension, abduction and medial rotation of the humerus
Correct Answer: Flexion, adduction and medial rotation of the humerus
Explanation:The pectoralis major is a muscle that runs across the top of the chest and connects to a ridge on the back of the humerus (the bone of the upper arm). Adduction, or lowering, of the arm (opposed to the deltoideus muscle) and rotation of the arm forward around the axis of the body are two of its main functions.
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This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 22
Incorrect
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A 27-year-old man was sent to the emergency department by ambulance with suspected anaphylaxis. What is the best first-line treatment for this patient?
Your Answer: 5 mg of adrenaline intramuscularly
Correct Answer: 500 micrograms of adrenaline intramuscularly
Explanation:Anaphylaxis is the sudden onset of systemic hypersensitivity due to IgE-mediated chemical release from mast cells and basophils. If anaphylaxis is suspected, 500 micrograms of adrenaline should be administered promptly (0.5 ml of 1:1000 solution). In anaphylaxis, the intramuscular route is the most immediate approach; the optimal site is the anterolateral aspect of the middle part of the thigh. Intravenous adrenaline should only be given by people who are well-versed in the use and titration of vasopressors in their routine clinical practice.
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This question is part of the following fields:
- Pharmacology
- Respiratory
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Question 23
Incorrect
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An very unwell patient is receiving treatment in your hospital's HDU and is found to have an Escherichia coli O157 infection.Which one of these statements about Escherichia coli O157 is true?
Your Answer: It is enteroaggregative
Correct Answer: Haemolytic uraemic syndrome develops in approximately 6% of patients
Explanation:Escherichia coli O157 is a serotype of Escherichia coli.The Escherichia coliO157 strain is ‘enterohaemorrhagic’ and causes severe forms of acute haemorrhagic diarrhoea. It can also cause non-haemorrhagic diarrhoea. Incubation period of Escherichia coli O157 is usually 3-4 days and bloody diarrhoea usually begins on the 3rd or 4th day of the infection.Infections with Escherichia coliO157 are more common during the warmer months than in winter.Haemolytic uraemic syndrome develops in approximately 6% of patients. It is commonly seen in children and in the elderly. Escherichia coli O157 can also cause:Haemorrhagic colitisHaemolytic uraemic syndromeThrombotic thrombocytopenic purpura but not immune thrombocytopenic purpura.
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This question is part of the following fields:
- Microbiology
- Specific Pathogen Groups
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Question 24
Incorrect
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Which of the following nerves supply the superficial head of the flexor pollicis brevis muscle?
Your Answer: The palmar digital branch of the median nerve
Correct 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.
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This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 25
Incorrect
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The Philadelphia chromosome is a genetic abnormality associated primarily with which of the following malignancies:
Your Answer: Chronic lymphocytic leukaemia
Correct Answer: Chronic myeloid leukaemia
Explanation:Chronic myeloid leukaemia (CML) is a clonal disorder of a pluripotent stem cell. The disease accounts for around 15% of leukaemias and may occur at any age. The diagnosis of CML is rarely difficult and is assisted by the characteristic presence of the Philadelphia (ph) chromosome. This disease occurs in either sex, most frequently between the ages of 40 and 60 years. In up to 50% of cases the diagnosis is made incidentally from a routine blood count. Leucocytosis is the main feature, with a complete spectrum of myeloid cells seen in the peripheral blood. The levels of neutrophils and myelocytes exceed those of blast cells and promyelocytes.Increased circulating basophils are a characteristic feature. Normochromic normocytic anaemia is usual. Platelet count may be increased (most frequently), normal or decreased. The clinical outlook is very good and 90% of patients can expect long-term control of disease.
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This question is part of the following fields:
- Haematology
- Pathology
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Question 26
Correct
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Which of the following best describes a natural killer cell:
Your Answer: A large granular lymphocyte that kills by inducing target cell apoptosis.
Explanation:Natural killer (NK) cells are cytotoxic CD8 positive cells that lack the T-cell receptor. They are large cells with cytoplasmic granules. NK cells are designed to kill target cells that have a low level of expression of HLA class I molecules, such as may occur during viral infection or on a malignant cell. NK cells do this by displaying several receptors for HLA molecules on their surface. When HLA is expressed on the target cell these deliver an inhibitory signal into the NK cell. When HLA molecules are absent on the target cell this inhibitory signal is lost and the NK cell can then kill its target. In addition, NK cells display antibody-dependent cell-mediated cytotoxicity. In this, antibody binds to antigen on the surface of the target cell and then NK cells bind to the Fc portion of the bound antibody and kill the target cell.
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This question is part of the following fields:
- Immune Responses
- Pathology
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Question 27
Correct
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The following structures all lie anteriorly to the oesophagus EXCEPT for the:
Your Answer: Thoracic duct
Explanation:Posterior to the oesophagus, the thoracic duct is on the right side inferiorly but crosses to the left more superiorly (at T5).
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This question is part of the following fields:
- Anatomy
- Thorax
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Question 28
Incorrect
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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 risk ratio of a hip fracture.
Your Answer: 0.33
Correct Answer: 0.4
Explanation:Relative risk (RR) is a ratio of the probability of an event occurring in the exposed group versus the probability of the event occurring in the non-exposed group.RR can be computed as the absolute risk of events in the treatment group (ART), divided by the absolute risk of events in the control group (ARC).RR = ART/ARCRR = (10/500) / (25/500)RR = 0.4Recall that:If RR < 1, then the intervention reduces the risk of the outcome.If RR = 1, then the treatment has no effect on the outcome.If RR > 1, then the intervention increases the risk of the outcome.
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This question is part of the following fields:
- Evidence Based Medicine
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Question 29
Incorrect
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A 28-year-old patient who has been in a car accident needs to be intubated using a rapid sequence induction. As an induction agent, you intend to use etomidate.Etomidate works by interacting with which type of receptor?
Your Answer: Dopamine
Correct Answer: Gamma-aminobutyric acid (GABA)
Explanation:Etomidate is a carboxylated imidazole derivative with a short half-life that is primarily used to induce anaesthesia.It is thought to modulate fast inhibitory synaptic transmission in the central nervous system by acting on GABA type A receptors.The dose for anaesthesia induction is 0.3 mg/kg. Etomidate takes 10-65 seconds to take effect after an intravenous injection, and it lasts 6-8 minutes. With repeated administration, the effects are non-cumulative.The relative cardiovascular stability of etomidate is noteworthy. During induction, it causes less hypotension than thiopental sodium and propofol. It’s also linked to a quick recovery without the hangover.Etomidate is a strong steroidogenesis inhibitor. The drug inhibits the enzymes responsible for adrenal 11 beta-hydroxylase and cholesterol cleavage, resulting in a decrease in cortisol and aldosterone synthesis for up to 24 hours after administration. It should not be used to maintain anaesthesia because of the adrenocortical suppression.Other side effects associated with etomidate use include:Vomiting and nauseaThe injection causes pain (in up to 50 percent )Phlebitis and thrombosis of the veinsHeart block and arrhythmiasHyperventilationApnoea and respiratory depressionIt has the potential to cause both hypo- and hypertension.Critically ill patients have a higher mortality rate.
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This question is part of the following fields:
- Anaesthesia
- Pharmacology
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Question 30
Incorrect
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The most common source of healthcare-associated bacteraemia is:
Your Answer: Urinary catheter
Correct Answer: Intravenous cannula
Explanation:Healthcare-associated bacteraemia is most commonly caused by intravenous access. Any intravenous device that is left in place for a long time increases the risk of infection. It allows bacteria like Staphylococcus aureus and Staphylococcus epidermidis to enter the body.
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This question is part of the following fields:
- Microbiology
- Principles
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Question 31
Correct
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Which of the following cervical nerves is likely to be affected if your patient is complaining of elbow extension weakness and loss of sensation in her middle finger? She also has pain and tenderness in her cervical region, which is caused by a herniated disc, all after a whiplash-type injury in a car accident.
Your Answer: C7
Explanation:A C7 spinal nerve controls elbow extension and some finger extension. Damage to this nerve can result in a burning pain in the shoulder blade or back of the arms. The ability to extend shoulders, arms, and fingers may also be affected. Dexterity may also be compromised in the hands or fingers.
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This question is part of the following fields:
- Anatomy
- Central Nervous System
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Question 32
Incorrect
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A 22-year-old man comes to the emergency department with a human bite injury to his hand received from a punch during a fight 3 hours earlier outside a bar. On closer inspection, you discover bite marks on his first and second knuckles. Which of the following is the best treatment option for this patient:
Your Answer: Nil antibiotics at this stage
Correct Answer: Oral co-amoxiclav for 7 days
Explanation:Even if there is no evidence of infection, prophylactic antibiotics should be administered for all human bite wounds that are less than 72 hours old. The first-line therapy is 7 days of co-amoxiclav. In penicillin-allergic people, metronidazole + doxycycline is an option. Streptococcus spp., Staphylococcus aureus, Haemophilus spp., Eikenella corrodens, Bacteroides spp., and other anaerobes are the most prevalent organisms found in human bites.
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This question is part of the following fields:
- Infections
- Microbiology
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Question 33
Correct
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A patient is sent in by her GP with suspected ectopic pregnancy. Tubal ectopic pregnancies occur most commonly in which part of the uterine tube:
Your Answer: Ampulla
Explanation:Ectopic pregnancy most commonly occurs in the ampulla (70% of cases).
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This question is part of the following fields:
- Abdomen
- Anatomy
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Question 34
Incorrect
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Which of the following globin chains makes up haemoglobin A2 (HbA2)?
Your Answer: Two beta and two gamma chains
Correct Answer: Two alpha chains and two delta chains
Explanation:Haemoglobin is a 64.4 kd tetramer consisting of two pairs of globin polypeptide chains: one pair of alpha-like chains, and one pair of non-alpha chains. The chains are designated by Greek letters, which are used to describe the particular haemoglobin (e.g., Hb A is alpha2/beta2).Two copies of the alpha-globin gene (HBA2, HBA1) are located on chromosome 16 along with the embryonic zeta genes (HBZ). There is no substitute for alpha globin in the formation of any of the normal haemoglobins (Hb) following birth (e.g., Hb A, Hb A2, and Hb F). Thus, absence any alpha globin, as seen when all 4 alpha-globin genes are inactive or deleted is incompatible with extrauterine life, except when extraordinary measures are taken. A homotetramer of only alpha-globin chains is not thought to occur, but in the absence of alpha chains, beta and gamma homotetramers (HbH and Bart’s haemoglobin, respectively) can be found, although they lack cooperativity and function poorly in oxygen transport. The single beta-globin gene (HBB) resides on chromosome 11, within a gene cluster consisting of an embryonic beta-like gene, the epsilon gene (HBE1), the duplicated and nearly identical fetal, or gamma globin genes (HBG2, HBG1), and the poorly expressed delta-globin gene (HBD). A heme group, consisting of a single molecule of protoporphyrin IX co-ordinately bound to a single ferrous (Fe2+) ion, is linked covalently at a specific site to each globin chain. If the iron is oxidized to the ferric state (Fe3+), the protein is called methaemoglobin.Alpha globin chains contain 141 amino acids (residues) while the beta-like chains contain 146 amino acids. Approximately 75 percent of haemoglobin is in the form of an alpha helix. The non helical stretches permit folding of the polypeptide upon itself. Individual residues can be assigned to one of eight helices (A-H) or to adjacent non helical stretches.Heme iron is linked covalently to a histidine at the eighth residue of the F helix (His F8), at residue 87 of the alpha chain and residue 92 of the beta chain. Residues that have charged side groups, such as lysine, arginine, and glutamic acid, lie on the surface of the molecule in contact with the surrounding water solvent. Exposure of the hydrophilic (charged) amino acids to the aqueous milieu is an important determinant of the solubility of haemoglobin within the red blood cell and of the prevention of precipitation.The haemoglobin tetramer is a globular molecule (5.0 x 5.4 x 6.4 nm) with a single axis of symmetry. The polypeptide chains are folded such that the four heme groups lie in clefts on the surface of the molecule equidistant from one another.
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This question is part of the following fields:
- Basic Cellular
- Physiology
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Question 35
Incorrect
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Which of the following does not increase renal phosphate excretion?
Your Answer: Glucocorticoids
Correct Answer: Vitamin D
Explanation:PO43-renal excretion is regulated several mechanisms. These include:-parathyroid hormone – increases excretion by inhibiting reabsorption in the proximal tubule-acidosis – increases excretion-glucocorticoids – increases excretion-calcitonin – increases excretion-activated vitamin D – decreases excretion by increasing reabsorption in the distal tubule
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This question is part of the following fields:
- Physiology
- Renal
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Question 36
Incorrect
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The following all cause a left shift in the oxygen dissociation curve EXCEPT for:
Your Answer: Carbon monoxide poisoning
Correct Answer: Decrease in pH
Explanation:An increased affinity of haemoglobin for oxygen, shown by a left shift in the oxygen dissociation curve, is caused in the lungs by a rise in pH, a fall in PCO2,a decrease in temperature and a decrease in 2,3 -DPG. Carbon monoxide (CO) binds 240 times more strongly than O2to haemoglobin and by occupying O2-binding sites, reduces oxygen capacity. CO also increases oxygen affinity, shifting the oxygen haemoglobin curve to the left and making O2release to tissues more difficult.
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This question is part of the following fields:
- Physiology
- Respiratory
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Question 37
Incorrect
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At which opioid receptors do opioid analgesics act primarily?
Your Answer: Nociceptin
Correct Answer: Mu
Explanation:Opioid receptors are widely distributed throughout the central nervous system. Opioid analgesics mimic endogenous opioid peptides by causing prolonged activation of these receptors, mainly the mu(μ)-receptors which are the most highly concentrated in brain areas involved in nociception.
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This question is part of the following fields:
- Central Nervous System
- Pharmacology
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Question 38
Incorrect
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A 66-year-old male is brought to your clinic by his wife with the complaint of increasing confusion and disorientation over the past three days, along with decreased urination. She reports that he has been complaining of increasing pain in his back and ribs over the past three months. On examination, the patient looks anaemic, is not oriented in time, place and person and has tenderness on palpation of the lumbar spine and the 10th, 11th and 12th ribs. Blood tests show anaemia which is normocytic, normochromic, raised urea and creatinine and hypercalcemia. Which one of the following diagnoses is most likely in this case?
Your Answer: Vitamin B12 deficiency
Correct Answer: Multiple myeloma
Explanation:Multiple myeloma is a clonal abnormality affecting plasma cells in which there is an overproduction of functionless immunoglobulins. The most common patient complaint is bone pain, especially in the back and ribs. Anaemia and renal failure are common, along with hypercalcemia. Hypercalcemia may lead to an altered mental status, as in this case. Chronic lymphocytic leukaemia occurs due to the overproduction of lymphocytes, usually B cells. CLL may present with an asymptomatic elevation of B cells. Patients are generally more than 50 years old and present with non-specific fatigue and weight loss symptoms.There is no history of alcohol abuse in this case. Furthermore, patients with a history of alcohol abuse may have signs of liver failure, which are not present here. Metastatic prostate cancer would most often cause lower backache as it metastasises first to the lumbar spine via the vertebral venous plexus. A patient with Vitamin B12 deficiency would have anaemia, megaloblastic, hypersegmented neutrophils, and signs of peripheral neuropathy.
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This question is part of the following fields:
- Haematology
- Pathology
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Question 39
Incorrect
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You suspect an anaphylactic reaction in a patient who is hypotensive, with trouble breathing after eating peanuts. Which of the following diagnostic tests will confirm this?
Your Answer: ANCA autoantibodies
Correct Answer: Mast cell tryptase
Explanation:The concentration of serum tryptase rises in anaphylaxis and anaphylactoid responses. Because tryptase is a significant component of mast cell granules, mast cell degranulation causes elevated tryptase levels in the blood. Although tryptase levels are not always high during anaphylaxis, it is considered a particular marker.
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This question is part of the following fields:
- Pharmacology
- Respiratory
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Question 40
Incorrect
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Which of the following nerves has been damaged when a patient presents with a foot drop?
Your Answer: Tibial nerve
Correct Answer: Common peroneal nerve
Explanation:The common peroneal nerve often referred to as the common fibular nerve, is a major nerve that innervates the lower extremity. It is one of the two major branches off the sciatic nerve and receives fibres from the posterior divisions of L4 through S2 nerve roots. The common peroneal nerve separates from the sciatic nerve in the distal posterior thigh proximal to the popliteal fossa. After branching off of the sciatic nerve, it continues down the thigh, running posteroinferior to the biceps femoris muscle, and crosses laterally to the head of the lateral gastrocnemius muscle through the posterior intermuscular septum. The nerve then curves around the fibular neck before dividing into two branches, the superficial peroneal nerve (SPN) and the deep peroneal nerve (DPN). The common peroneal nerve does not have any motor innervation before dividing; however, it provides sensory innervation to the lateral leg via the lateral sural nerve.The superficial peroneal nerve innervates the lateral compartment of the leg, and the deep peroneal nerve innervates the anterior compartment of the leg and the dorsum of the foot. These two nerves are essential in the eversion of the foot and dorsiflexion of the foot, respectively. The superficial and deep peroneal nerves provide both motor and sensory innervation.The most common presentation with common peroneal nerve injury or palsy is acute foot drop, although symptoms may be progressive and can include sensory loss or pain. Weakness in foot eversion may occur if the superficial peroneal nerve component is involved.
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This question is part of the following fields:
- Anatomy
- Lower Limb
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Question 41
Correct
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You review a 34-year-old man with lower back pain and plan to prescribe him ibuprofen and codeine phosphate. His only past medical history of note is depression, for which he takes fluoxetine.Which of the following scenarios would prompt you to consider the co-prescription of a PPI for gastro-protection? Select ONE answer only.
Your Answer: Co-prescription of fluoxetine
Explanation:Patients at risk of gastro-intestinal ulceration (including the elderly) who need NSAID treatment should receive gastroprotective treatment. The current recommendations by NICE suggest that gastro-protection should be considered if patients have ≥1 of the following:Using maximum recommended dose of an NSAIDAged 65 or olderHistory of peptic ulcer or GI bleedingConcomitant use of medications that increase risk:Low dose aspirinAnticoagulantsCorticosteroidsAnti-depressants including SSRIs and SNRIsRequirements for prolonged NSAID usage:Patients with OA or RA at any ageLong-term back pain if older than 45It is suggested that if required, either omeprazole 20 mg daily or lansoprazole 15-30 mg daily should be the PPIs of choice.This patient is on 400 mg of ibuprofen TDS, but the maximum recommended dose of ibuprofen is 2.4 g daily. Co-prescription of codeine, raised BMI, and a family history of peptic ulceration would also not prompt gastro-protection.
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This question is part of the following fields:
- Musculoskeletal Pharmacology
- Pharmacology
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Question 42
Incorrect
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Cardiac myocytes are connected to each other by which of the following:
Your Answer: T-tubules
Correct Answer: Intercalated discs
Explanation:Adjacent cardiac myocytes are connected to each other by intercalated discs. The intercalated discs provide both a structural attachment by ‘glueing’ cells together at desmosomes and an electrical contact made up of proteins called connexons, called a gap junction, which essentially creates a low-resistance pathway between cells.
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This question is part of the following fields:
- Cardiovascular
- Physiology
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Question 43
Incorrect
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Lidocaine's mechanism of action as a local aesthetic is as follows:
Your Answer: Blocks efflux of K+
Correct Answer: Blocks influx of Na+ through voltage-gated Na+ channels
Explanation:Local anaesthetics prevent generation/conduction of nerve impulses by reducing sodium permeability and increasing action potential threshold; inhibits depolarization, which results in blockade of conduction
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This question is part of the following fields:
- Anaesthesia
- Pharmacology
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Question 44
Incorrect
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Which of the following blood groups is the least common in the UK:
Your Answer: AB and A
Correct Answer: AB
Explanation:Blood group O is the most common in the UK (46 %), followed by group A (42 %), group B (9 %) and finally group AB (3 %).Blood group O has no antigens, but both anti-A and anti-B antibodies and thus is the universal donor. Blood group AB has both A and B antigens but no antibodies and thus is the universal recipient.Blood group A has A antigens and anti-B antibodies and blood group B has B antigens and anti-A antibodies.
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This question is part of the following fields:
- Immune Responses
- Pathology
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Question 45
Incorrect
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Following an injury sustained during a rugby match, a 16-year-old boy is brought to the Emergency Department by his mother. His forearm appears to be deformed, and you believe he has a distal radius fracture. A numerical rating scale is used to assess his pain, and the triage nurse informs you that he is in moderate pain.'The RCEM guidance recommends which of the following analgesics for the treatment of moderate pain in a child of this age?
Your Answer: Intravenous morphine 0.1-0.2 mg/kg
Correct Answer: Oral codeine phosphate 1 mg/kg
Explanation:According to a 2018 audit conducted by the Royal College of Emergency Medicine (RCEM), the standard of care for children presenting to EDs with fractured limbs has deteriorated, with most patients waiting longer than ever before for pain relief. More than one-tenth of the children who came in with significant pain from a limb fracture received no pain relief at all.For all patients, including children, the Agency for Health Care Policy and Research (AHCPR) in the United States recommends using the ABCs of pain management:A – Ask about pain regularly. Assess pain systematically.B – Believe the patient and family in their reports of pain and what relieves it.C – Choose pain control options appropriate for the patient, family, and setting.D – Deliver interventions in a timely, logical, coordinated fashion.E – Empower patients and their families. Enable patients to control their course to the greatest extent possible.The RCEM guidelines recommend assessing a child’s pain within 15 minutes of arrival. This is a fundamental requirement. For the assessment of pain in children, a variety of rating scales are available; which one is used depends on the child’s age and ability to use the scale. These are some of them:Faces of Wong-Baker Scale for assessing painScale of numerical evaluationThe behavioural scale is a scale that measures how people behave.The RCEM has provided the following visual guide:The RCEM has established the following guidelines for when patients in severe pain should receive appropriate analgesia:100% within 60 minutes of arrival or triage, whichever is earliest75% within 30 minutes of arrival or triage, whichever is earliest50% within 20 minutes of arrival or triage, whichever is earliest
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This question is part of the following fields:
- CNS Pharmacology
- Pharmacology
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Question 46
Incorrect
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Which of the following best describes the order in which blood passes through the nephron?Â
Your Answer: Afferent arteriole→Glomerular capillary→Peritubular capillary→Efferent arteriole→Vasa recta
Correct Answer: Afferent arteriole→Glomerular capillary→Efferent arteriole→Peritubular capillary→Vasa recta
Explanation:The nephron’s blood flow is as follows:Afferent arteriole – Glomerular capillary – Efferent arteriole – Peritubular capillary – Vasa recta – Afferent arteriole – Glomerular capillary – Efferent arteriole – Peritubular capillary – Vasa rectaThe kidney is the only vascular network in the body with two capillary beds. With arterioles supplying and draining the glomerular capillaries, higher hydrostatic pressures at the glomerulus are maintained, allowing for better filtration. A second capillary network at the tubules enables for secretion and absorption in the tubules, as well as concentrating urine.
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This question is part of the following fields:
- Physiology
- Renal Physiology
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Question 47
Incorrect
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One of the following pathogens is a conditional pathogen:
Your Answer: Treponema pallidum
Correct Answer: Neisseria meningitidis
Explanation:Obligate pathogens include Mycobacterium TB, HIV, Treponema pallidum, and Neisseria gonorrhoeae. Neisseria meningitidis, on the other hand, is a conditional pathogen.
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This question is part of the following fields:
- Microbiology
- Principles
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Question 48
Incorrect
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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: Autosomal recessive
Correct 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.
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This question is part of the following fields:
- Haematology
- Pathology
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Question 49
Incorrect
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A 70-year-old patient diagnosed with Cushing's syndrome and has a history of weight gain, hypertension, and easy bruising.Which of these assertions about Cushing's syndrome is correct?
Your Answer:
Correct Answer: Diagnosis can be confirmed by a dexamethasone suppression test
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.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.Because cortisol enhances the vasoconstrictive impact of endogenous adrenaline, patients with Cushing’s syndrome are usually hypertensive.Hyperglycaemia (due to insulin resistance) rather than hypoglycaemia is a common symptom.Cortisol levels fluctuate throughout the day, with the greatest levels occurring around 0900 hours and the lowest occurring at 2400 hrs during sleep. The diurnal swing of cortisol levels is lost in Cushing’s syndrome, and levels are greater throughout the 24-hour period. In the morning, levels may be normal, but they may be high at night-time, when they are generally repressed.A dexamethasone suppression test or a 24-hour urine free cortisol collection can both be used to establish the existence of Cushing’s syndrome.
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This question is part of the following fields:
- Endocrine Physiology
- Physiology
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Question 50
Incorrect
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A dermatological examination on a patient presenting with a lump shows a solid, well circumscribed, lump measuring 0.8 cm in diameter.Which one of these best describes the lump you have found on examination?
Your Answer:
Correct Answer: Nodule
Explanation:A nodule is a solid, well circumscribed, raised area that lies in or under the skin and measures greater than 0.5 cm in diameter. They are usually painless.A vesicle is a visible collection of fluid measuring less than 0.5 cm in diameter. A macule is a flat, well circumscribed area of discoloured skin less than 1 cm in diameter with no changes in the thickness or texture of the skin.A papule is a solid, well circumscribed, skin elevation measuring less than 0.5 cm in diameter.A plaque is a palpable skin lesion that is elevated and measures >1cm in diameter
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This question is part of the following fields:
- General Pathology
- Pathology
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SESSION STATS - PERFORMANCE PER SPECIALTY
