-
Question 1
Correct
-
The lymph drainage of the anal canal above the pectinate line is initially to the:
Your 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
-
-
Question 2
Correct
-
A 34-year-old woman was diagnosed with multiple sclerosis two years ago. Her symptoms have been steadily deteriorating, with no intervals of remission in sight.
Which of the following aspects of nerve conduction is disrupted by multiple sclerosis?
Your Answer: Saltatory conduction
Explanation:Local currents propagate action potentials down the axons of neurons. This local current flow following depolarisation results in the depolarisation of the neighbouring axonal membrane, and when this region approaches the threshold, more action potentials are generated and so forth. Due to the refractory period, portions of the membrane that have recently depolarized will not depolarize again, resulting in the action potential only being able to go in one direction.
The square root of axonal diameter determines the velocity of the action potential; the axons with the biggest diameter have the quickest conduction velocities. When a neuron is myelinated, the speed of the action potential rises as well.
The myelin sheath is an insulating coating that surrounds certain neural axons. By increasing membrane resistance and decreasing membrane capacitance, the myelin sheath improves conduction. This enables faster electrical signal transmission via a neuron, making them more energy-efficient than non-myelinated neuronal axons.
Electrical impulses are quickly transmitted from one node to the next, causing depolarization of the membrane above the threshold and triggering another action potential, which is then transmitted to the next node. An action potential is rapidly conducted down a neuron in this manner. Saltatory conduction is the term for this.
Multiple sclerosis is an example of a clinical disorder in which the myelin sheath is affected. It is an immune-mediated disorder in which certain nerve cells in the brain and spinal cord become demyelinated. The ability of some areas of the nervous system to properly transmit action potentials is disrupted by demyelination, resulting in a variety of neurological symptoms and indications. -
This question is part of the following fields:
- Basic Cellular Physiology
- Physiology
-
-
Question 3
Incorrect
-
An elderly man with chronic heart and lung disease develops Legionnaires' disease. Which of the following clinical features is NOT typical of Legionnaires' disease:
Your Answer: Nausea, vomiting and diarrhoea
Correct Answer: Confusion
Explanation:Legionella pneumophilais a Gram negative bacterium that is found in natural water supplies and in the soil, transmitted predominantly via inhalation of aerosols generated from contaminated water (direct person-to-person spread of infected patients does not occur). It is the cause of Legionnaires’ disease. Outbreaks of Legionnaires’ disease have been linked to poorly maintained air conditioning systems, whirlpool spas and hot tubs.
The clinical features of the pneumonic form of Legionnaires’ disease include:
Mild flu-like prodrome for 1-3 days
Cough (usually non-productive and occurs in approximately 90%)
Pleuritic chest pain
Haemoptysis
Headache
Nausea, vomiting and diarrhoea
AnorexiaLegionella pneumophilainfections can be successfully treated with macrolide antibiotics, such as erythromycin, or quinolones, such as ciprofloxacin. Tetracyclines, such as doxycycline, can also be used.
The syndrome of inappropriate antidiuretic hormone secretion (SIADH) can occur with Legionnaires’ disease and will result in hyponatraemia as is seen in this case.
Legionella pneumophilainfections are resistant to amoxicillin but can be successfully treated with macrolide antibiotics, such as erythromycin, or quinolones, such as ciprofloxacin. Tetracyclines, such as doxycycline, can also be used. The majority of cases of Legionnaires’ disease are caused by Legionella pneumophila, however many other species of Legionella have been identified.
Legionella longbeachae is another less commonly encountered species that has also been implicated in outbreaks. It is predominantly found in soil and potting compost, and has caused outbreaks of Pontiac fever, the non-respiratory and less severe variant of Legionnaires’ disease. -
This question is part of the following fields:
- Microbiology
- Pathogens
-
-
Question 4
Incorrect
-
The weight distribution in a group of patients included in a study was normal. The patients averaged 80 kg in weight. 5 kg was determined to be the standard deviation. Which of the following statements most accurately describes this group of patients:
Your Answer: 95% of the patients will weigh between 75 and 85 kg.
Correct Answer: 68% of the patients will weigh between 75 and 85 kg.
Explanation:We can estimate the range of values that would be anticipated to include particular proportions of observations if we know the mean and standard deviation of a collection of normally distributed data: 68.2 percent of the sample results fall within a one SD range above and below the mean (+/- 1 SD), implying that 68 percent of the patients will weigh between 75 and 85 kg. Because +/- 2 SD encompasses 95.4 percent of the data, around 95 percent of the patients will weigh between 70 and 90 kg. +/- 3 SD encompasses 99.7% of the values, implying that nearly all of the patients will weigh between 65 and 95 kg.
-
This question is part of the following fields:
- Evidence Based Medicine
- Statistics
-
-
Question 5
Incorrect
-
Which of the following best describes the popliteal artery's course?
Your Answer: Terminates as the posterior tibial and the fibular artery
Correct Answer: After exiting the popliteal fossa terminates at the lower border of the popliteus muscle
Explanation:The popliteal artery divides into the anterior and posterior tibial arteries at the lower border of the popliteus after exiting the popliteal fossa between the gastrocnemius and popliteus muscles.
-
This question is part of the following fields:
- Anatomy
- Lower Limb
-
-
Question 6
Correct
-
You investigated a patient with a chest infection and want to start antibiotics right away. The patient says they she can't take cephalosporins when you ask about allergies.
Choose the 'second-generation' cephalosporin from the following choices?Your Answer: Cefuroxime
Explanation:Cephalosporins of the first generation include cephalexin, cefradine, and cefadroxil. Urinary tract infections, respiratory tract infections, otitis media, and skin and soft-tissue infections are all treated with them.
Second-generation cephalosporins include cefuroxime, cefaclor, and cefoxitin. These cephalosporins are less vulnerable to beta-lactamase inactivation than the ‘first-generation’ cephalosporins. As a result, they’re effective against germs that are resistant to other antibiotics, and they’re especially effective against Haemophilus influenzae.
Cephalosporins of the third generation include cefotaxime, ceftazidime, and ceftriaxone. They are more effective against Gram-negative bacteria than second generation’ cephalosporins. They are, however, less effective against Gram-positive bacteria such Staphylococcus aureus than second-generation cephalosporins.
-
This question is part of the following fields:
- Infections
- Pharmacology
-
-
Question 7
Correct
-
A patient presents with an adducted eye at rest which cannot abduct past the midline, which of the following cranial nerves is most likely to be affected:
Your Answer: Abducens nerve
Explanation:Abducens nerve palsies result in a convergent squint at rest (eye turned inwards) with inability to abduct the eye because of unopposed action of the rectus medialis. The patient complains of horizontal diplopia when looking towards the affected side. With complete paralysis, the eye cannot abduct past the midline.
-
This question is part of the following fields:
- Anatomy
- Cranial Nerve Lesions
-
-
Question 8
Correct
-
Which of the following local anaesthetics has the longest duration of action:
Your Answer: Bupivacaine
Explanation:Bupivacaine has a longer duration of action than the other local anaesthetics, up to 8 hours when used for nerve blocks. It has a slow onset, taking up to 30 minutes for full effect. It is often used in lumbar epidural blockade and is particularly suitable for continuous epidural analgesia in labour, or for postoperative pain relief. It is the principal drug used for spinal anaesthesia.
-
This question is part of the following fields:
- Anaesthesia
- Pharmacology
-
-
Question 9
Correct
-
How is filtered K+mainly reabsorbed in the thick ascending limb of the loop of Henle:
Your Answer: Secondary active transport via Na + /K + /2Cl - cotransporter
Explanation:Around 30% of filtered K+is reabsorbed in the thick ascending limb of the loop of Henle, primarily via the luminal Na+/K+/2Cl-cotransporter, but there is also significant paracellular reabsorption, encouraged by the positive potential in the tubular lumen.
-
This question is part of the following fields:
- Physiology
- Renal
-
-
Question 10
Correct
-
Regarding the management of diabetic ketoacidosis (DKA), insulin should initially be given:
Your Answer: At a concentration of 1 unit/mL at a fixed rate of 0.1 units/kg/hour
Explanation:An intravenous insulin infusion should be started at a concentration of 1 unit/mL, at a fixed rate of 0.1 units/kg/hour. Established subcutaneous long-acting insulin therapy should be continued concomitantly. Blood ketone and blood glucose concentrations should be checked hourly and the insulin infusion rate adjusted accordingly. Blood ketone concentration should fall by at least 0.5 mmol/litre/hour and blood glucose concentration should fall by at least 3 mmol/litre/hour.
-
This question is part of the following fields:
- Endocrine
- Pharmacology
-
-
Question 11
Correct
-
The enzyme protein gastric lipase is responsible for the breakdown of lipids in the stomach.
Which of the following cell types secretes gastric lipase?Your Answer: Chief cells
Explanation:Gastric lipase, commonly known as LIPF, is an acidic lipase released by gastric chief cells, which are found deep within the stomach lining’s mucosal layer. It’s an enzymatic protein that’s in charge of fat digestion in the stomach.
-
This question is part of the following fields:
- Gastrointestinal Physiology
- Physiology
-
-
Question 12
Incorrect
-
A 38-year-old woman presented to the emergency room after an incident of slipping and falling onto her back and left hip. Upon physical examination, it was noted that she has pain on hip flexion, but normal hip adduction. Which of the following muscles was most likely injured in this case?
Your Answer: Adductor longus
Correct Answer: Sartorius
Explanation:The hip adductors are a group of five muscles located in the medial compartment of the thigh. These muscles are the adductor longus, adductor brevis, adductor magnus, gracilis, and pectineus.
The hip flexors consist of 5 key muscles that contribute to hip flexion: iliacus, psoas, pectineus, rectus femoris, and sartorius.
-
This question is part of the following fields:
- Anatomy
- Lower Limb
-
-
Question 13
Correct
-
Which of the following causes increased aldosterone secretion:
Your Answer: Decreased blood volume
Explanation:Decreased blood volume stimulates the secretion of renin (because of decreased renal perfusion pressure) and initiates the renin-angiotensin-aldosterone cascade. Angiotensin-converting enzyme (ACE) inhibitors block the cascade by decreasing the production of angiotensin. Hyperosmolarity stimulates antidiuretic hormone (ADH) [not aldosterone] secretion. Hyperkalaemia, not hypokalaemia, directly stimulates aldosterone secretion by the adrenal cortex. ANPÂ inhibits renin secretion, thereby inhibiting the production of angiotensin and aldosterone.
-
This question is part of the following fields:
- Physiology
- Renal
-
-
Question 14
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 15
Correct
-
Question 16
Incorrect
-
Which of the following statements regarding hookworm is FALSE:
Your Answer: Diagnosis is by direct visualisation of characteristic eggs in stool on microscopy.
Correct Answer: Transmission of hookworm is via ingestion of contaminated food and water.
Explanation:The hookworm life cycle begins with the passage of eggs from an adult host into the stool. Hookworm eggs hatch in the soil to release larvae that mature into infective larvae. Infection is usually transmitted by larval penetration into human skin (duodenal infection may also be transmitted by the oral route). From the skin, larvae migrate into the blood vessels and are carried to the lungs, where they penetrate the pulmonary alveoli, ascend the bronchial tree to the pharynx, and are swallowed.
-
This question is part of the following fields:
- Microbiology
- Pathogens
-
-
Question 17
Incorrect
-
A 29-year-old woman with anaphylactic reaction to peanuts, had to use her EpiPen on the way to hospital.
What percentage of patients with anaphylactic reaction suffer a biphasic response?.Your Answer: 10%
Correct Answer: 20%
Explanation:About 20% of patients that suffer an anaphylactic reaction suffer a biphasic response 4-6 hours after the initial response (sometimes up to 72 hours after).
-
This question is part of the following fields:
- General Pathology
- Pathology
-
-
Question 18
Correct
-
A patient with history of weight loss and diarrhoea was found out to have Giardia lamblia in her stool since returning from a holiday to Nepal.
Which of the following statements is considered true regarding the life cycle of Giardia lamblia?Your Answer: Trophozoites attach to the intestinal wall via a specialised sucking disc
Explanation:Cysts are resistant forms and are responsible for transmission of giardiasis. Both cysts and trophozoites can be found in the faeces (diagnostic stages). The cysts are hardy and can survive several months in cold water. Infection occurs by the ingestion of cysts in contaminated water, food, or by the faecal-oral route (hands or fomites).
In the small intestine, excystation releases trophozoites (each cyst produces two trophozoites).
Trophozoites multiply by longitudinal binary fission, remaining in the lumen of the proximal small bowel where they can be free or attached to the mucosa by a ventral sucking disk.
Encystation occurs as the parasites transit toward the colon. The cyst is the stage found most commonly in non diarrheal faeces.
Because the cysts are infectious when passed in the stool or shortly afterward, person-to-person transmission is possible. While animals are infected with Giardia, their importance as a reservoir is unclear. -
This question is part of the following fields:
- Microbiology
- Principles Of Microbiology
-
-
Question 19
Incorrect
-
Which of these immunoglobulin molecules can cross the placenta?
Your Answer: IgM and IgG
Correct Answer: IgG
Explanation:An important mechanism that provides protection to the foetus is placental transfer of maternal IgG antibodies while his/her humoral response is inefficient. The only antibody class that significantly crosses the human placenta is IgG.
-
This question is part of the following fields:
- Immune Responses
- Pathology
-
-
Question 20
Incorrect
-
A lesion to which part of the optic radiation will result in contralateral homonymous inferior quadrantanopia?
Your Answer: Left parietal lobe
Correct Answer: Right parietal lobe
Explanation:A visual loss in the lower left quadrant in both visual fields is an indication of an inferior homonymous. This is due to a lesion of the superior fibres of the optic radiation in the parietal lobe on the contralateral side of the visual pathway.
-
This question is part of the following fields:
- Anatomy
- Central Nervous System
-
-
Question 21
Correct
-
A 14-year-old female is brought to the Emergency Room by her mother after a fall from a tree in which she injured her elbow. An elbow fracture is suspected based on the examination findings, and she is given Entonox for analgesia as her elbow is set in a cast.
Which one of the following statements regarding this drug is true?Your Answer: It can cause inhibition of vitamin B12 synthesis
Explanation:Entonox is a mixture of 50% Oxygen and 50% nitrous oxide and is given in an inhaled form as a quick form of analgesia. Entonox causes non-competitive inhibition of NMDA (N-methyl-D-aspartate) receptors, which are a subtype of the glutamate receptor.
It is stored in blue and white cylinders and administered via a pressure regulator and demand valve. The administration of this medicine reduces pain and anxiety in paediatric and dental procedures ands during labour.
Effects are apparent after 20 seconds, and peak action occurs after 3 to 5 minutes as it is a drug with a rapid onset and the patient will also recover rapidly from its effects. Entonox is widely used as it does not accumulate in the body and does not cause many side effects. However, a notable side effect is the inhibition of Vitamin B12 synthesis.
-
This question is part of the following fields:
- Anaesthesia
- Pharmacology
-
-
Question 22
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 toxicity
Chronic digoxin toxicity
Cardiac arrest
Life-threatening arrhythmia
Potassium level > 5 mmol/l
>10 mg digoxin ingested (adult)
>4 mg digoxin ingested (child)
Digoxin level > 12 ng/ml
Cardiac arrest
Life-threatening arrhythmia
Significant gastrointestinal symptoms
Symptoms of digoxin toxicity -
This question is part of the following fields:
- Cardiovascular Pharmacology
- Pharmacology
-
-
Question 23
Correct
-
Which of the following is the primary indication for loop diuretics?
Your Answer: Acute pulmonary oedema
Explanation:Loop diuretics have long been the cornerstone of pulmonary oedema treatment, with furosemide being the most commonly used of these drugs. Premedication with drugs that decrease preload (e.g., nitro-glycerine [NTG]) and afterload (e.g., angiotensin-converting enzyme [ACE] inhibitors) before the administration of loop diuretics can prevent adverse hemodynamic changes.
-
This question is part of the following fields:
- Cardiovascular
- Pharmacology
-
-
Question 24
Correct
-
Which of the following is NOT a typical clinical feature of diabetic ketoacidosis:
Your Answer: Cheyne–Stokes respiration
Explanation:Clinical features of DKA:
Symptoms: Polyuria, polydipsia, thirst, lethargy, weight loss, nausea, vomiting, anorexia, abdominal pain, dehydration, headache, altered mental state
Signs: Dry mucous membranes, ketotic breath, tachycardia, hypotension, Kussmaul breathing, focal signs of precipitant e.g. infection -
This question is part of the following fields:
- Endocrine
- Physiology
-
-
Question 25
Correct
-
The Auerbach's plexus is a set of ganglia that controls peristalsis and is located in the gut wall.
Auerbach's plexus is located in which layer of the gut wall?Your Answer: Muscular layer
Explanation:The Auerbach’s plexus, also known as the myenteric plexus, is a collection of ganglia that controls peristalsis and is located in the gut wall.
In the muscular layer of the wall, it is located between the circular and longitudinal muscle layers. It is a linear network of linked neurons that runs the length of the gastrointestinal system. The myenteric plexus generates an increase in gut wall tone and the strength of rhythmical contractions when stimulated.
-
This question is part of the following fields:
- Gastrointestinal Physiology
- Physiology
-
-
Question 26
Correct
-
Which coronary artery is mostly likely affected if an ECG shows ST segment elevation in leads II, III and aVF, and ST segment depression in V1-V3?
Your Answer: Right coronary artery
Explanation:A posterior wall MI occurs when posterior myocardial tissue (now termed inferobasilar), usually supplied by the posterior descending artery — a branch of the right coronary artery in 80% of individuals — acutely loses blood supply due to intracoronary thrombosis in that vessel. This frequently coincides with an inferior wall MI due to the shared blood supply.
The ECG findings of an acute posterior wall MI include the following:
1. ST segment depression (not elevation) in the septal and anterior precordial leads (V1-V4). This occurs because these ECG leads will see the MI backwards; the leads are placed anteriorly, but the myocardial injury is posterior.
2. A R/S wave ratio greater than 1 in leads V1 or V2.
3. ST elevation in the posterior leads of a posterior ECG (leads V7-V9). Suspicion for a posterior MI must remain high, especially if inferior ST segment elevation is also present.
4. ST segment elevation in the inferior leads (II, III and aVF) if an inferior MI is also present.The following ECG leads determine the location and vessels involved in myocardial infarction:
ECG Leads Location Vessel involved
V1-V2 Septal wall Left anterior descending
V3-V4 Anterior wall Left anterior descending
V5-V6 Lateral wall Left circumflex artery
II, III, aVF Inferior wall Right coronary artery (80%) or Left circumflex artery (20%)
I, aVL High lateral wall Left circumflex artery
V1, V4R Right ventricle Right coronary artery
V7-V9 Posterior wall Right coronary artery -
This question is part of the following fields:
- Anatomy
- Thorax
-
-
Question 27
Correct
-
Fat necrosis is typically seen in which of the following:
Your Answer: Acute pancreatitis
Explanation:Fat necrosis typically occurs following either direct trauma or from enzymatic lipolysis in acute pancreatitis, where release of triglyceride elicits a rapid inflammatory response and fat is phagocytosed by neutrophils and macrophages with subsequent fibrosis.
-
This question is part of the following fields:
- Inflammatory Responses
- Pathology
-
-
Question 28
Correct
-
Question 29
Correct
-
The Meissner’s plexus acts as the main control for gastrointestinal secretion and local blood flow within the gut.
The Meissner’s plexus lies in which layer of the gut wall?Your Answer: Submucosa
Explanation:The Meissner’s plexus (submucosal plexus), an enteric nervous plexus, acts as the main control for gastrointestinal secretion and local blood flow within the gut.
It is located in the submucosal layer on the inner surface of the muscularis externa.
-
This question is part of the following fields:
- Gastrointestinal Physiology
- Physiology
-
-
Question 30
Correct
-
A 32-old woman comes for a follow-up visit after being discharged on medications for her newly diagnosed epilepsy. She now complains of a tremor in her arm when she holds a tray in her hand. You examine the patient and notice she has developed postural tremors.
Which of the following medications for epilepsy is most likely responsible for this tremor?Your Answer: Sodium valproate
Explanation:A postural tumour is observed when a person maintains a position against gravity, such as holding the arms outstretched. (The patient holding her tray against gravity)
Sodium valproate is the most commonly prescribed medication for epilepsy. It is commonly associated with tremors as valproate-induced tremors occur in around 6-45% of patients. The tremors are commonly postural, but a resting tremor may also occur.
Approximately 25% of patients taking sodium valproate are found to develop a tremor within 3-12 months of initiating therapy.
-
This question is part of the following fields:
- CNS Pharmacology
- Pharmacology
-
-
Question 31
Correct
-
A patient with a wound infection on his right leg has reddening and oedema of the surrounding muscles. His condition has worsened considerably over the past few hours with the area now appearing blackened. There is also palpable crepitus under the skin. You suspect gas gangrene.
Which statement about Clostridium perfringens is true?Your Answer: Gas gangrene is caused by the release of an alpha-toxin
Explanation:Clostridium perfringens, a Gram-positive, anaerobic, spore forming rod-shaped, pathogenic bacterium is the most commonly associated with gas gangrene (85-90% of cases), although other species can also be implicated.
Clostridium perfringens is capsulate and produces a range of toxins. Alpha-toxin is the most important and is the cause of gas gangrene.
Gas gangrene develops when a devitalized wound becomes infected with Clostridium perfringens spores from the environment. The spores germinate and multiplies in the ischaemic conditions, releasing toxins, which further damage tissues.
Usually, the clinical features of gas gangrene appear within 24 hours of injury.
Clostridium perfringens spores are not destroyed by cooking. During slow cooling and unrefrigerated storage, they germinate to form vegetative cells.
-
This question is part of the following fields:
- Microbiology
- Specific Pathogen Groups
-
-
Question 32
Incorrect
-
You've been summoned to a young man in the resus area who is experiencing an SVT. You decide to use adenosine after trying several vagal manoeuvres without success.
Which of the following is the correct adenosine mechanism of action?Your Answer: Inhibits the Na/K ATPase in cardiac myocytes
Correct Answer: Opens K + channels in the heart
Explanation:The purine nucleoside adenosine is used to diagnose and treat paroxysmal supraventricular tachycardia. Adenosine works by stimulating A1-adenosine receptors and opening potassium channels that are sensitive to acetylcholine. This causes the atrioventricular (AV) node’s cell membrane to become hyperpolarized, slowing conduction by inhibiting calcium channels.
Patients who have had a heart transplant are extremely sensitive to the effects of adenosine and should start with a lower dose of 3 mg, then 6 mg, and finally 12 mg.Dipyridamole potentiates the effects of adenosine, so it should be used with caution in patients who are taking it.
The use of adenosine is contraindicated in the following situations:
Asthma
COPD (chronic obstructive pulmonary disease)
Decompensated heart failureÂ
Long QT syndrome
AV block in the second or third degree
Sinusitis is a condition in which the sinuses become (unless pacemaker fitted)
Hypotension that is severe -
This question is part of the following fields:
- Cardiovascular Pharmacology
- Pharmacology
-
-
Question 33
Correct
-
A 62-year-old woman has reduced urine output, nausea, and confusion. Renal function tests and other investigations done leads to a diagnosis of acute kidney injury (AKI). Which one of these is consistent with a diagnosis of AKI?
Your Answer: A rise in serum creatinine of 26 μmol/L within 48 hours
Explanation:AKI is diagnosed based on an acutely rising serum creatinine and/or reduction in urine output.
-
AKI can often be non-oliguric.
AKI is present if any one or more of the following criteria is met:
-
A rise in serum creatinine of ≥26 micromol/L (≥0.3 mg/dL) within 48 hours
-
A rise in serum creatinine to ≥1.5 times baseline, which is known or presumed to have occurred within the past 7 days (in practice you can use the lowest value from the past 3 months as the baseline for the patient)
-
Urine volume <0.5 ml/kg/hour for at least 6 hours.
-
-
This question is part of the following fields:
- General Pathology
- Pathology
-
-
Question 34
Incorrect
-
A 59-year-old man presents with a goitre, increased sweating, weight loss, and palpitations. A diagnosis of hyperthyroidism is suspected.
What is the most appropriate first-line investigation?
Your Answer: Antithyroglobulin antibodies
Correct Answer: TSH level
Explanation:A thyroid function test is used in the diagnosis of hyperthyroidism.
Serum TSH should be the first-line investigation for patients with suspected hyperthyroidism as it has the highest sensitivity and specificity for hyperthyroidism.A normal TSH level almost always excludes the diagnosis, though there are rare exceptions to this.
Antithyroglobulin antibodies are commonly present in Graves’ disease, but the test has a sensitivity of 98% and specificity of 99, and is not widely available.
Radioactive iodine uptake scan using iodine-123 – shows low uptake in thyroiditis but high in Graves’ disease and toxic multinodular goitre. It is however, not first-line investigation in this case
Thyroid ultrasound scan – is a cost-effective and safe alternative to the radioactive iodine uptake scan.
-
This question is part of the following fields:
- Endocrine Physiology
- Physiology
-
-
Question 35
Correct
-
A 71-year-old man treated with antibiotics for a chest infection returns with a profuse, offensive smelling diarrhoea. A diagnosis of Clostridium difficile diarrhoea is made after investigations.
Which antibiotic is associated with the greatest risk of causing Clostridium Difficile diarrhoea?
Your Answer: Ciprofloxacin
Explanation:Clostridium difficile, a Gram-positive, anaerobic, spore forming bacteria is present in the gut of approximately 3% of healthy adults (2012 UK HPA estimates). Following use of broad spectrum antibiotics, which alter normal gut flora, Clostridium difficile infection (CDI) occurs. About 80% of Clostridium Difficile infections are seen in people over the age of 65 and its main clinical features are:
Abdominal cramps, severe bloody and/or watery diarrhoea, offensive smelling diarrhoea, and fever.CDI is the most severe consequence of antibiotic treatment and is a major cause of morbidity and mortality.
Risk for CDI has been found to be greatest with clindamycin followed by fluoroquinolones Tetracyclines are not associated with risk for CDI. -
This question is part of the following fields:
- Microbiology
- Specific Pathogen Groups
-
-
Question 36
Incorrect
-
Aldin is a 24-year-old male patient who arrives at the emergency department diagnosed with psittacosis based on his symptoms and history of being a pigeon enthusiast. Which of the following is the causative bacteria of psittacosis?
Your Answer: Legionella pneumophila
Correct Answer: Chlamydia psittaci
Explanation:Chlamydia psittaci is a microorganism that is commonly found in birds.
These bacteria can infect people and cause psittacosis. Psittacosis is an infectious disease that may cause high fever and pneumonia associated with headaches, altered mental state, and hepatosplenomegaly.
-
This question is part of the following fields:
- Infections
- Microbiology
-
-
Question 37
Correct
-
Cardiac myocytes contract by excitation-contraction coupling, very much like skeletal myocytes. On the other hand, calcium-induced calcium release (CICR) is a mechanism that is unique to Cardiac myocytes. The influx of calcium ions (Ca 2+) into the cell causes a 'calcium spark,' which causes more ions to be released into the cytoplasm.
In CICR, which membrane protein in the sarcoplasmic reticulum is involved?Your Answer: Ryanodine receptor
Explanation:Cardiac myocytes contract by excitation-contraction coupling, just like skeletal myocytes. Heart myocytes, on the other hand, utilise a calcium-induced calcium release mechanism that is unique to cardiac muscle (CICR). The influx of calcium ions (Ca2+) into the cell causes a ‘calcium spark,’ which causes more ions to be released into the cytoplasm.
An influx of sodium ions induces an initial depolarisation, much as it does in skeletal muscle; however, in cardiac muscle, the inflow of Ca2+ sustains the depolarisation, allowing it to remain longer. Due to potassium ion (K+) inflow, CICR causes a plateau phase in which the cells remain depolarized for a short time before repolarizing. Skeletal muscle, on the other hand, repolarizes almost instantly.
The release of Ca2+ from the sarcoplasmic reticulum is required for calcium-induced calcium release (CICR). This is mostly accomplished by ryanodine receptors (RyR) on the sarcoplasmic reticulum membrane; Ca2+ binds to RyR, causing additional Ca2+ to be released.
-
This question is part of the following fields:
- Basic Cellular Physiology
- Physiology
-
-
Question 38
Correct
-
The patients listed below have been diagnosed with a variety of ailments.
In which of the following situations would aspirin be an effective treatment option?Your Answer: A 36-year-old with an acute migraine (dose of 900-1000 mg)
Explanation:A study published in the Cochrane Database of Systematic Reviews in 2010 found that a single 1000-mg dose of aspirin is effective in treating acute migraine. It was discovered that 24 percent of aspirin users were pain-free after two hours, compared to 11 percent of placebo users. Because the BNF recommends a maximum dose of 900 mg for analgesia and most non-proprietary aspirin comes in a dose of 300 mg, a dose of 900 mg is frequently prescribed in the UK.
Because aspirin is not recommended for children under the age of 16 due to the risk of Reye’s syndrome, it would be inappropriate to give it to the 12-year-old with the viral URTI.
For uncomplicated dental pain, aspirin is an acceptable option, but not for patients who are taking warfarin. The combination of aspirin’s antiplatelet action and warfarin’s anticoagulation properties puts the patient at high risk of bleeding. Furthermore, aspirin can deplete the therapeutic levels of warfarin by displacing it from plasma proteins. It would be better to use another NSAID or analgesic.
In gout, aspirin should be avoided because it reduces urate clearance in the urine and interferes with the action of uricosuric agents. Naproxen, diclofenac, and indomethacin are better options.
Although aspirin is useful for inflammatory pains, the dose of aspirin required for an adequate analgesic effect in severe pain is associated with significant side effects. Naproxen would be a better first-line treatment option.
-
This question is part of the following fields:
- Cardiovascular Pharmacology
- Pharmacology
-
-
Question 39
Correct
-
Regarding linear relationships between two variables, what does a positive correlation coefficient indicate:
Your Answer: The two variables are directly proportional
Explanation:A positive correlation coefficient means that the two variables are directly proportional e.g. height and weight in healthy growing children.
-
This question is part of the following fields:
- Evidence Based Medicine
- Statistics
-
-
Question 40
Correct
-
A known epileptic is transported in status epilepticus by ambulance. On the way to the hospital, she took some diazepam.
Which of the following statements about diazepam is correct?Your Answer: It crosses into breast milk
Explanation:Diazepam boosts GABA’s effects, giving it sedative, hypnotic, anxiolytic, anticonvulsant, and muscle-relaxing properties. It can be administered orally, rectally, or intravenously.
With a half-life of 20-100 hours, it is a long-acting benzodiazepine. Midazolam, oxazepam, and alprazolam are examples of short-acting benzodiazepines with a half-life of less than 12 hours (Xanax).
If used in the presence of hepatic impairment, benzodiazepines can cause coma. If treatment is necessary, benzodiazepines with shorter half-lives should be used in lower doses. Diazepam is a sedative that crosses into breast milk and should be avoided by breastfeeding mothers.
-
This question is part of the following fields:
- CNS Pharmacology
- Pharmacology
-
-
Question 41
Correct
-
A 54 year old patient presents with vertigo, ipsilateral hemiataxia, dysarthria, ptosis and miosis.
Which of these blood vessels has most likely been occluded?
Your Answer: Posterior inferior cerebellar artery
Explanation:Posterior inferior cerebellar artery (PICA) occlusion is characterised by vertigo, ipsilateral hemiataxia, dysarthria, ptosis and miosis. PICA occlusion causes infarction of the posterior inferior cerebellum, inferior cerebellar vermis and lateral medulla.
-
This question is part of the following fields:
- Anatomy
- Central Nervous System
-
-
Question 42
Incorrect
-
A blood transfusion is given to a 52-year-old woman. She develops chills and rigours shortly after the transfusion begins.
The following are her observations: Temperature 40°C, HR 116 bpm, BP 80/48, SaO 2 97 percent on air.
Which of the following treatments is the most appropriate?Your Answer: Supportive measures and paracetamol
Correct Answer: Stop the transfusion and administer antibiotics
Explanation:Bacterial infections are common in the following situations:
Platelet transfusions are associated with a higher risk of bacterial infection (as platelets are stored at room temperature)
Immersion in a water bath thawed previously frozen components.
Components of red blood cells that have been stored for several weeks
Gram-positive and Gram-negative bacteria have both been linked to transfusion-transmitted bacterial infection, but Gram-negative bacteria are linked to a higher rate of morbidity and mortality.
Yersinia enterocolitica is the most common bacterial organism linked to transfusion-transmitted bacterial infection. This organism can multiply at low temperatures while also utilising iron as a nutrient. As a result, it’s well-suited to proliferating in blood banks.The following are some of the most common clinical signs and symptoms of a bacterial infection transmitted through a blood transfusion. These symptoms usually appear shortly after the transfusion begins:
Fever is very high.
Rigours and chills
Vomiting and nausea
Tachycardia
Hypotension
Collapse of the circulatory systemIf a bacterial infection from a transfusion is suspected, the transfusion should be stopped right away. Blood cultures and a Gram stain should be requested, as well as broad-spectrum antibiotics. In addition, the blood pack should be returned to the blood bank for an urgent culture and Gram-stain.
-
This question is part of the following fields:
- Haematology
- Pathology
-
-
Question 43
Correct
-
You examine a resuscitated patient who has been diagnosed with ventricular tachycardia. The patient's hemodynamics are normal. You intended to prescribe amiodarone to him, but you can't because he has a contraindication.
In these circumstances, which of the following is a contraindication to using amiodarone?Your Answer: Sinus node disease
Explanation:Amiodarone is an anti-arrhythmic medication that can be used to treat both ventricular and atrial arrhythmias.
The use of amiodarone is contraindicated in the following situations:
Conduction disturbances that are severe (unless pacemaker fitted)
Sinus node disease is a condition that affects the lymph nodes in (unless pacemaker fitted)
Sensitivity to iodine
Blockage of the Sino-atrial heart valve (except in cardiac arrest)
Bradycardia in the sinuses (except in cardiac arrest)
Thyroid disorders -
This question is part of the following fields:
- Cardiovascular Pharmacology
- Pharmacology
-
-
Question 44
Correct
-
Insulin is a very important peptide hormone produced by the islets of Langerhans in the pancreas.
Insulin is synthesised by which of the following cell types within the islets of Langerhans? Select ONE answer only.Your Answer: Beta cells
Explanation:Insulin is produced by beta cells, located centrally within the islets of Langerhans, in the endocrine tissues of the pancreas. Insulin is a polypeptide hormone consisting of two short chains (A and B) linked by disulphide bonds. Proinsulin is synthesised as a single-chain peptide. Within storage granules, a connecting peptide (C peptide) is removed by proteases to yield insulin. Insulin release is stimulated initially during eating by the parasympathetic nervous system and gut hormones such as secretin, but most output is driven by the rise in plasma glucose concentration that occurs after a meal. The effects of insulin are mediated by the receptor tyrosine kinase.
-
This question is part of the following fields:
- Endocrine Physiology
- Physiology
-
-
Question 45
Correct
-
One of the following statements about acute lymphoblastic leukaemia(ALL) is true.
Your Answer: It is classified using the FAB classification
Explanation:ALL affects children predominantly.
The CNS is commonly involved in ALL.
The Philadelphia chromosome is present in 25% of adult ALL and 5% of childhood ALL cases.
The cure rate in children is approximately 80% in children and 50% in adults.
ALL is classified into 3 groups using the French-American-British (FAB) classification:
ALL-L1: small uniform cells
ALL-L2: large varied cells
ALL-L3: large varied cells with vacuoles. -
This question is part of the following fields:
- Haematology
- Pathology
-
-
Question 46
Correct
-
You examine a 79-year-old woman who has had hypertension and atrial fibrillation in the past. Her most recent blood tests show that she has severe renal impairment.
Which medication adjustments should you make in this patient's case?Your Answer: Reduce dose of digoxin
Explanation:Digoxin is excreted through the kidneys, and impaired renal function can lead to elevated digoxin levels and toxicity.
The patient’s digoxin dose should be reduced in this case, and their digoxin level and electrolytes should be closely monitored. -
This question is part of the following fields:
- Cardiovascular Pharmacology
- Pharmacology
-
-
Question 47
Incorrect
-
Following the administration of a drug that was started a few months earlier, a patient presents with features of peripheral neuropathy.
Which of the following drugs is most likely to cause peripheral neuropathy?
Your Answer: Amiodarone
Correct Answer: Isoniazid
Explanation:Isoniazid, a first-line agent for the treatment of tuberculosis, has the commonest side effect of peripheral neuropathy. It occurs in up to 20% of patients taking the drug at a dose > 6 mg/kg daily.
Isoniazid combines with pyridoxine (vitamin B6) to form hydrazone, which is excreted in the urine. This causes a deficiency of biologically active pyridoxine leading to peripheral neuropathy.
Peripheral neuropathy of isoniazid is prevented by the co-administration of pyridoxine at a dose of 10 mg for each 100 mg of isoniazid given.
-
This question is part of the following fields:
- Infections
- Pharmacology
-
-
Question 48
Correct
-
A 58-year-old woman presents with symptoms of increase in weight, proximal muscular weakening and withering, easy bruising, and acne. You notice that she has a full, plethoric aspect to her face, as well as significant supraclavicular fat pads, when you examine her. She has previously been diagnosed with Cushing's syndrome.
Cushing's syndrome is most commonly caused by which of the following?Your Answer: Iatrogenic administration of corticosteroids
Explanation:Cushing’s syndrome is a group of symptoms and signs brought on by long-term exposure to high amounts of endogenous or exogenous glucocorticoids. Cushing’s syndrome affects about 10-15 persons per million, and it is more common in those who have had a history of obesity, hypertension, or diabetes.
Iatrogenic corticosteroid injection is the most prevalent cause of Cushing’s syndrome. Cushing’s illness is the second most prevalent cause of Cushing’s syndrome. Cushing’s disease is distinct from Cushing’s syndrome in that it refers to a single cause of the illness, a pituitary adenoma that secretes high quantities of ACTH, which raises cortisol levels.
Cushing’s syndrome has several endogenous sources, including:
Cushing’s disease is caused by a pituitary adenoma.
Adrenal adenoma Ectopic corticotropin syndrome, e.g. small cell cancer of the lung
Adrenal carcinoma is a cancer of the adrenal gland.
Hyperplasia of the adrenal glands -
This question is part of the following fields:
- Endocrine Physiology
- Physiology
-
-
Question 49
Incorrect
-
Which of the following statements is considered correct regarding Klebsiella infections?
Your Answer: Klebsiella pneumoniae is most commonly associated with chronic bronchiectasis
Correct Answer: Klebsiella spp. are non-motile
Explanation:Klebsiella is a Gram-negative, rod-shaped, non-motile bacteria. The absence of motility distinguishes Klebsiella spp. from most other members of the family Enterobacteriaceae.
K. pneumoniae is the most commonly isolated species and has the distinct feature of possessing a large polysaccharide capsule. The capsule offers the organism protection against phagocytosis and antimicrobial absorption,
contributing to its virulence.Colonization of gram-negative bacilli in the respiratory tracts of hospitalized patients, particularly by K. pneumoniae, increases with the length of hospital stay. It is a frequent cause of lower respiratory tract infections among hospitalized patients and in immunocompromised hosts such as newborns,
elderly patients, and seriously ill patients on respirators. -
This question is part of the following fields:
- Microbiology
- Specific Pathogen Groups
-
-
Question 50
Correct
-
Monoamine oxidase is primarily involved in the degradation of which of the following:
Your Answer: Noradrenaline
Explanation:Catecholamines are broken down extracellularly and in the liver by catechol-O-methyltransferase (COMT) and intracellularly by monoamine oxidase (MAO).
-
This question is part of the following fields:
- Endocrine
- Physiology
-
SESSION STATS - PERFORMANCE PER SPECIALTY
