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Question 1
Incorrect
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In the Emergency Department, a 35-year-old woman actively seizing is brought in. She is quickly shifted into the resuscitation room and is administered a dose of benzodiazepine. The seizure is quickly terminated.
Once the patient is stable, she tells you she is a known case of epilepsy and takes phenytoin to control it.
Which of the following is the primary mechanism of action of phenytoin?Your Answer: GABA receptor agonist
Correct Answer: Sodium channel blocker
Explanation:Phenytoin is in the anticonvulsants class of drugs and is used in the management and treatment of the following:
1. epilepsy
2. generalized tonic-clonic seizures
3. complex partial seizures
4. status epilepticus.It works by inactivating the voltage-gated sodium channels responsible for increasing the action potential. It is non-specific and targets almost all voltage-gated sodium channel subtypes. More specifically, phenytoin prevents seizures by inhibiting the positive feedback loop that results in neuronal propagation of high-frequency action potentials.
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This question is part of the following fields:
- CNS Pharmacology
- Pharmacology
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Question 2
Incorrect
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Which of the following laboratory findings is NOT typical of Hodgkin lymphoma:
Your Answer: Eosinophilia
Correct Answer: Basophilia
Explanation:Features may include:Normochromic normocytic anaemia is most common; bone marrow failure involvement is unusual in early disease, but if it occurs bone marrow failure may develop with leucoerythroblastic anaemiaOne-third of patients have a neutrophilia; eosinophilia is frequentAdvanced disease is associated with lymphopenia and loss of cell-mediated immunityPlatelet count is normal or increased in early disease and reduced in later stagesESR and CRP are usually raised (ESR is useful in monitoring disease progress)Serum LDH is raised initially in 30-40% of casesDiagnosis is made by histological examination of an excised lymph nodeThe distinctive multinucleate polypoid RS cell is central to the diagnosis of the four classic types of HL (95% of cases)
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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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One of your patients is in resuscitation and is suffering from kidney failure. The intensive care outreach team arrives to assess them and determines that a dopamine infusion is necessary.
Dopamine primarily acts on which of the following receptors at low doses?Your Answer: Dopamine receptors
Explanation:Dopamine is a catecholamine that occurs naturally and is used to treat low cardiac output, septic shock, and renal failure. It is both adrenaline and noradrenaline’s immediate precursor.
Dopamine acts on D1 and D2 dopamine receptors in the renal, mesenteric, and coronary beds at low doses (1-5 g/kg/min). Dopamine causes a significant decrease in renal vascular resistance and an increase in renal blood flow at these doses. Within this dose range, it is also involved in central modulation of behaviour and movement.
Dopamine stimulates beta- and alpha-adrenergic receptors directly and indirectly at higher doses. Beta-stimulation predominates at a rate of 5-10 g/kg/min, resulting in a positive inotropic effect that increases cardiac output and coronary blood flow. Alpha-stimulation predominates at infusion rates greater than 15 g/kg/min, resulting in peripheral vasoconstriction and an increase in venous return and systolic blood pressure.
Below is a summary of the mechanisms and effects of various inotropic agents:
Inotrope
Mechanism
Effects
Adrenaline (epinephrine)
Beta-1 and -2 agonist at increasing doses;
Alpha-agonist at high doses
Increased cardiac output;
Vasoconstriction at higher doses
Noradrenaline (norepinephrine)
Mainly alpha-agonist;
Beta-1 and -2 agonist at increasing doses
Vasoconstriction;
Some increased cardiac output
Dopamine
Dopamine agonist at low doses;
Beta-1 and -2 agonist at increasing doses;
Alpha-agonist at high doses
Increased cardiac output;
Vasoconstriction at higher doses
Dobutamine
Mainly beta-1 agonist
Increased cardiac output -
This question is part of the following fields:
- Cardiovascular Pharmacology
- Pharmacology
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Question 4
Incorrect
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A 30-year-old man presents with diarrhoea, fever, vomiting, and abdominal cramps. A stool culture was ordered and showed growth of Salmonella spp.
Among the following serotypes of Salmonella spp., which is considered to be the most common cause of salmonella gastroenteritis?Your Answer: Serotype A
Correct Answer: Serotype D
Explanation:A common cause of gastroenteritis, Salmonella enteritidis, and Salmonella typhi, which causes enteric fever, are both group D. Therefore, serotype D Salmonella species are most commonly associated with gastroenteritis.
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This question is part of the following fields:
- Microbiology
- Specific Pathogen Groups
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Question 5
Correct
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Regarding haemoglobin, which of the following statements is CORRECT:
Your Answer: In degradation of haemoglobin, the haem group is split from the haemoglobin and converted to biliverdin and ultimately to bilirubin.
Explanation:Haemoglobin is composed of four polypeptide globin chains each with its own iron containing haem molecule. Haem synthesis occurs largely in the mitochondria by a series of biochemical reactions commencing with the condensation of glycine and succinyl coenzyme A under the action of the key rate-limiting enzyme delta-aminolevulinic acid (ALA) synthase. The globin chains are synthesised by ribosomes in the cytosol. Haemoglobin synthesis only occurs in immature red blood cells.
There are three types of haemoglobin in normal adult blood: haemoglobin A, A2 and F:
– Normal adult haemoglobin (HbA) makes up about 96 – 98 % of total adult haemoglobin, and consists of two alpha (α) and two beta (β) globin chains.Â
– Haemoglobin A2 (HbA2), a normal variant of adult haemoglobin, makes up about 1.5 – 3.5 % of total adult haemoglobin and consists of two α and two delta (δ) globin chains.
– Foetal haemoglobin is the main Hb in the later two-thirds of foetal life and in the newborn until approximately 12 weeks of age. Foetal haemoglobin has a higher affinity for oxygen than adult haemoglobin.Â
Red cells are destroyed by macrophages in the liver and spleen after , 120 days. The haem group is split from the haemoglobin and converted to biliverdin and then bilirubin. The iron is conserved and recycled to plasma via transferrin or stored in macrophages as ferritin and haemosiderin. An increased rate of haemoglobin breakdown results in excess bilirubin and jaundice. -
This question is part of the following fields:
- Basic Cellular
- Physiology
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Question 6
Incorrect
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An analytical study is conducted to compare the risk of stroke between Ticagrelor therapy and Warfarin therapy among patients with atrial fibrillation. The following is obtained from the study:
No. of patients who took Ticagrelor: 300
No. of patients who took Ticagrelor and suffered a stroke: 30
No. of patients who took Warfarin: 500
No. of patients who took Warfarin and suffered a stroke: 20
Compute for the absolute risk reduction of a stroke, with Warfarin as the standard of treatment.Your Answer: 0.06
Correct Answer: -0.06
Explanation:Absolute risk reduction (ARR) is computed as the difference between the absolute risk in the control group (ARC) and the absolute risk in the treatment group (ART).
Since Warfarin is the standard of treatment, Warfarin is considered as the control group.
ARR = ARC-ART
ARR = (20/500) – (30/300)
ARR = -0.06This means that there is increased risk of stroke in the treatment group, which is the Ticagrelor group.
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This question is part of the following fields:
- Evidence Based Medicine
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Question 7
Correct
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Caseous necrosis is typically seen in which of the following:
Your Answer: Tuberculosis
Explanation:Caseous necrosis is most commonly seen in tuberculosis. Histologically, the complete loss of normal tissue architecture is replaced by amorphous, granular and eosinophilic tissue with a variable amount of fat and an appearance reminiscent of cottage cheese.
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This question is part of the following fields:
- Inflammatory Responses
- Pathology
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Question 8
Incorrect
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Which type of collagen is initially laid down in early wound healing:
Your Answer: II
Correct Answer: III
Explanation:Fibroblasts migrate to the wound (about 2 – 5 days after wounding), proliferate and secrete extracellular matrix comprising mainly collagen (type III) and fibronectin to plug the gap.
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This question is part of the following fields:
- Pathology
- Wound Healing
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Question 9
Incorrect
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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: Hyponatraemic metabolic alkalosis
Correct 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:
Hypokalaemia
Metabolic alkalosis
Hypertension
Normal or slightly raised sodium levels -
This question is part of the following fields:
- Endocrine Physiology
- Physiology
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Question 10
Incorrect
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Which of the following is NOT a mineralocorticoid effect of corticosteroids:
Your Answer: Hypertension
Correct Answer: Hyperglycaemia
Explanation:Mineralocorticoid side effects include:hypertensionsodium retentionwater retention and oedemapotassium losscalcium loss
Glucocorticoid side effects include:weight gainhyperglycaemia and diabetesosteoporosis and osteoporotic fracturesmuscle wasting (proximal myopathy)peptic ulceration and perforationpsychiatric reactions -
This question is part of the following fields:
- Endocrine
- Pharmacology
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Question 11
Incorrect
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Which of the following infections is vancomycin most likely prescribed for?
Your Answer: Gas gangrene
Correct Answer: Clostridium difficile colitis
Explanation:125 mg PO q6hr for 10 days is indicated for treatment of Clostridium difficile (C. difficile)-associated diarrhoea
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This question is part of the following fields:
- Infections
- Pharmacology
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Question 12
Incorrect
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A 30-year-old man present to the ED with abdominal pain, nausea and vomiting. It has been present for the past two days.
Which of the following statements regarding diarrhoea and vomiting is true?
Your Answer: Rotavirus is only spread via the faeco-oral route
Correct Answer: E.Coli can cause diarrhoea and renal failure
Explanation:Escherichia coli strain 0157 causes enterohaemorrhagic diarrhoea and can lead to renal failure, haemolytic anaemia and thrombocytopenia.
Norwalk virus is an RNA virus.
Although transmission of rotavirus is primarily through the faeco-oral route, airborne spread has been seen in some cases.
Cryptosporidium are protozoa with acid fast walls and are resistant to both chlorine treatment and conventional filtering methods.
There is no therapy effective in treating cryptosporidium diarrhoea as the protozoa is not susceptible to antibiotics.
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This question is part of the following fields:
- Microbiology
- Specific Pathogen Groups
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Question 13
Correct
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Which of the following is where the rectovesical fascia is located:
Your Answer: Between the fundus of the bladder and the ampulla of the rectum
Explanation:In a triangular area between the vasa deferentia, the bladder and rectum are separated only by rectovesical fascia, commonly known as Denonvillier’s fascia.
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This question is part of the following fields:
- Abdomen
- Anatomy
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Question 14
Correct
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All of the following statements are considered true regarding likelihood ratios, except:
Your Answer: A likelihood ratio less than 1 indicates that the result is associated with the presence of the disease
Explanation:The Likelihood Ratio (LR) is the likelihood that a given test result would be expected in a patient with the target disorder compared to the likelihood that that same result would be expected in a patient without the target disorder.
The LR is used to assess how good a diagnostic test is and to help in selecting an appropriate diagnostic tests or sequence of tests. They have advantages over sensitivity and specificity because they are less likely to change with the prevalence of the disorder, they can be calculated for several levels of the symptom/sign or test, they can be used to combine the results of multiple diagnostic test and they can be used to calculate post-test probability for a target disorder.
A LR greater than 1 produces a post-test probability which is higher than the pre-test probability. An LR less than 1 produces a post-test probability which is lower than the pre-test probability. When the pre-test probability lies between 30 and 70 per cent, test results with a very high LR (say, above 10) rule in disease. An LR below 1 produces a post-test probability les than the pre-test probability. A very low LR (say, below 0.1) virtually rules out the chance that the patient has the disease.
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This question is part of the following fields:
- Evidence Based Medicine
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Question 15
Incorrect
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Glomerular filtration rate can be calculated using any substance that:
Your Answer: is freely filtered and secreted by the nephron
Correct Answer: is freely filtered and neither reabsorbed nor secreted by the nephron
Explanation:Clearance of a substance can provide an accurate estimate of the glomerular filtration rate (GFR) provided that the substance is:freely filterednot reabsorbed in the nephronnot secreted in the nephronnot synthesised or metabolised by the kidney
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This question is part of the following fields:
- Physiology
- Renal
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Question 16
Correct
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You suspect that your patient with polycystic kidney disease has developed a berry aneurysm as a complication of his disease. The patient complains of a sudden, severe headache. You are guessing subarachnoid haemorrhage secondary to a ruptured berry aneurysm as the cause of his severe headaches. What is the most likely location of his aneurysm?
Your Answer: Anterior communicating artery
Explanation:One of the complications that polycystic kidney disease may cause is the development of a brain aneurysm.
A berry aneurysm is the most common type of brain aneurysm.
The Circle of Willis, where the major blood vessels meet at the base of the brain, is where it usually appears. The most common junctions of the Circle of Willis where an aneurysm may occur include the anterior communicating artery (35%), internal carotid artery (30%), the posterior communicating artery and the middle cerebral artery (22%), and finally, the posterior circulation sites, most commonly the basilar artery tip.
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This question is part of the following fields:
- Anatomy
- Central Nervous System
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Question 17
Correct
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A 32-year-old man is dehydrated as he presents with severe vomiting and diarrhoea. He urgently requires resuscitation with intravenous fluid administration. He is also administered metoclopramide.
Which of the following is the true mechanism of action of metoclopramide?Your Answer: Dopamine receptor antagonism
Explanation:Metoclopramide is used to treat nausea and vomiting. It works by blocking the central and peripheral D2 (dopamine 2) receptors in the medullary chemoreceptor trigger zone in the vomiting centre (area postrema). It decreases the sensitivity of the visceral sensory nerves that transmit from the GI system to the vomiting centre. Blockade of inhibitory dopamine receptors in the GI tract may allow stimulatory actions of ACh at muscarinic synapses to predominate.
At high doses, metoclopramide also blocks type-2 serotonin receptors though the effect is much weaker.
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This question is part of the following fields:
- CNS Pharmacology
- Pharmacology
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Question 18
Incorrect
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Which of the following statements is incorrect regarding the Na+/K+ATPase pump?
Your Answer: The Na + /K + ATPase pump is found on cell membranes.
Correct Answer: The Na + /K + ATPase pump moves 3 Na + ions into the cell for every 2 K + ions out.
Explanation:In order for primary active transport to pump ions against their electrochemical gradient, chemical energy is used in the form of ATP. The Na+/K+-ATPase antiporter pump uses metabolic energy to move 3 Na+ions out of the cell for every 2 K+ions in, against their respective electrochemical gradients. As a result, the cell the maintains a high intracellular concentration of K+ions and a low concentration of Na+ions.
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This question is part of the following fields:
- Basic Cellular
- Physiology
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Question 19
Correct
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Beta cells of the endocrine pancreas produce which of the following hormones:
Your Answer: Insulin
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.
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This question is part of the following fields:
- Endocrine
- Physiology
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Question 20
Correct
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A patient with a recent diagnosis of Hepatitis B would like to find out further information regarding his diagnosis and prognosis.
Which among the following statements is considered true regarding Hepatitis B?Your Answer: 60-65% of patients that contract hepatitis B show subclinical disease
Explanation:As the immune response is activated, the virus is slowly cleared from the system, and most patients become non-infectious. In adults, about 50% of infections are asymptomatic; 20% to 30% of patients exhibit clinical jaundice but have a benign resolution of the infection. Therefore, about 80% of infections do not cause serious sequelae. The risk for chronic infection is inversely proportional to age at time of infection, with approximately 90% of infants and only 3% of adults developing a chronic infection.
Individuals with a chronic infection have a higher risk of liver disease, such as cirrhosis or hepatic carcinoma. -
This question is part of the following fields:
- Microbiology
- Specific Pathogen Groups
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Question 21
Correct
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When calculating the ventilation over perfusion ratio of a male patient, you should remember the ideal V/Q ratio for this patient to compare with his results. What is the approximate ventilation value for a healthy male patient?
Your Answer: 5 L/min
Explanation:The ventilation/perfusion ratio (V/Q ratio) is a ratio used to assess the efficiency and adequacy of the matching ventilation and perfusion. The ideal V/Q ratio is 1. In an average healthy male, the ventilation value is approximately 5 L/min and the perfusion value is approximately 5 L/min.
Any mismatch between ventilation and perfusion will be evident in the V/Q ratio. If perfusion is normal but ventilation is reduced, the V/Q ratio will be less than 1, whereas if ventilation is normal but perfusion is reduced, the V/Q ratio will be greater than 1. If the alveoli were ventilated but not perfused at all, then the V/Q ratio would be infinity.
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This question is part of the following fields:
- Physiology
- Respiratory Physiology
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Question 22
Correct
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A 66-year-old patient attends the Emergency Department with chest pain. His ECG and troponin are suggestive of a new myocardial infarction. You have explained the condition and the prognosis. He asks you about how the damaged area of his heart will heal following this.
Which answer best describes the process of myocardial healing following myocardial infarction? Select ONE answer only.Your Answer: The damaged myocardium will form non-contractile scar tissue
Explanation:Myocardial cells are unable to regenerate, they are unable to divide in response to tissue injury. The remain permanently in G0 and cannot progress to G1. If a segment of muscle dies, for example in myocardial infarction, this tissue will be replaced by scar tissue if the patient recovers. This scar tissue is non-contractile and therefore the remaining myocardium must work harder to maintain cardiac output. As a consequence the remaining undamaged myocardium undergoes compensatory hypertrophy without cell division.
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This question is part of the following fields:
- General Pathology
- Pathology
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Question 23
Incorrect
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Streptococcus pneumoniae is commonly implicated in all of the following infectious diseases EXCEPT for:
Your Answer: Pneumonia
Correct Answer: Impetigo
Explanation:Impetigo is a highly contagious infection of the superficial epidermis that most commonly affects young children but can occur in any age group. In children it is the most common bacterial skin infection and it is the third most common skin disease overall, behind dermatitis and viral warts.
The commonest causative organism is Staphylococcus aureus. Streptococcus pyogenesis the second commonest and causes fewer cases, either alone or in combination withS. aureus.The streptococcal form tends to be commoner in warmer, more humid climates. (Hirschmann JV. Impetigo: etiology and therapy. Curr Clin Top Infect Dis. 2002;22:42–51.)
Impetigo is most commonly spread by direct person-to-person contact, and can spread rapidly through families and school classes. It can also, less commonly, be spread by indirect contact.
There are two main forms of impetigo:
Non-bullous impetigo – lesions usually start as tiny pustules or vesicles that evolve rapidly into honey-crusted plaques that tend to be under 2 cm in diameter. These can be itchy but are rarely painful.
Bullous impetigo – lesions have a thin roof and tend to rupture spontaneously. This type is more likely to be painful and may be associated with systemic upset. -
This question is part of the following fields:
- Microbiology
- Pathogens
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Question 24
Correct
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Regarding propofol, which of the following statements is INCORRECT:
Your Answer: A lower induction dose of propofol is required in children.
Explanation:Elderly patients have a reduced volume of distribution and slower clearance of the drug. They are therefore more sensitive to the effects of propofol and the drug wears off more slowly. They need less of the drug, which should be injected slowly, monitoring its effect on the patient. The opposite is true in children, who need larger doses of propofol. This is particularly so in children under three years of age. Propofol is not recommended for induction of anaesthesia in children under one month of age or for maintenance of anaesthesia in children under three years old.
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This question is part of the following fields:
- Anaesthesia
- Pharmacology
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Question 25
Correct
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A 20-year-old male who is a known patient of sickle cell disease presents to the Emergency Room with a sustained erection that is extremely painful.
Out of the following clinical syndromes, which one does this patient most likely have?Your Answer: Priapism
Explanation:Sickling of red blood cells can lead to several different clinical syndromes. If the sickling occurs in the corpora cavernosa, it can lead to a sustained, painful erection of the penis, referred to as priapism. One of the complications is long-term impotence. It is important to seek a urological opinion immediately in this case, but in the interim, treat with perineal ice packs and walk up and down the stairs.
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This question is part of the following fields:
- Haematology
- Pathology
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Question 26
Incorrect
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A GP is considering prescribing a non-steroidal anti-inflammatory (NSAID) for pain relief for a patient with a knee injury
Which of these statements about NSAIDs is NOT true?Your Answer: Most NSAIDs act as non-selective inhibitors of the enzyme cyclo-oxygenase
Correct Answer: Side effects are less commonly seen with indomethacin than naproxen
Explanation:Most NSAIDs act as non-selective inhibitors of the enzyme cyclo-oxygenase (COX). They inhibit both COX-1 and COX-2 isoenzymes.
Only about 60% of patients will respond to any given NSAID.
It can take 21 days of treatment for a clinically appreciable reduction in inflammation to be apparent. If no improvement is seen after 21 days, the NSAID should be changed.
The use of NSAIDs in the 3rd trimester of pregnancy is associated with the following risks: delayed onset of labour, premature closure of ductus arteriosus and foetal kernicterus.
Side effects are lowest in Ibuprofen and highest in indomethacin. so side effects are more commonly seen with indomethacin than naproxen.
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This question is part of the following fields:
- Musculoskeletal Pharmacology
- Pharmacology
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Question 27
Correct
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Where is angiotensin I primarily converted to angiotensin II:
Your Answer: Lungs
Explanation:Angiotensin I is converted to angiotensin II by the removal of two C-terminal residues by the enzyme angiotensin-converting enzyme (ACE). This primarily occurs in the lungs, although it does also occur to a lesser degree in endothelial cells and renal epithelial cells.
The main actions of angiotensin II are:
Vasoconstriction of vascular smooth muscle (resulting in increased blood pressure)
Vasoconstriction of the efferent arteriole of the glomerulus (resulting in an increased filtration fraction and preserved glomerular filtration rate)
Stimulation of aldosterone release from the zona glomerulosa of the adrenal cortex
Stimulation of anti-diuretic hormone (vasopressin) release from the posterior pituitary
Stimulation of thirst via the hypothalamus
Acts on the Na+/H+ exchanger in the proximal tubule of the kidney to stimulate Na+reabsorption and H+excretion -
This question is part of the following fields:
- Physiology
- Renal
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Question 28
Incorrect
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You want to give colchicine to a patient who has acute gout. Which of the following is a contraindication to the use of colchicine?
Your Answer: Heart failure
Correct Answer: Blood dyscrasias
Explanation:Colchicine is used to prevent or treat gout attacks (flares). It works by reducing swelling and the development of uric acid crystals, which cause pain in the affected joint(s).
Colchicine should be avoided by patients who have blood dyscrasias or bone marrow disorders.
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This question is part of the following fields:
- Musculoskeletal
- Pharmacology
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Question 29
Correct
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Which of the following is required for vitamin B12 absorption:
Your Answer: Intrinsic factor
Explanation:Intrinsic factor is essential for the absorption of the small amounts of vitamin B12 normally present in the diet from the terminal ileum. The parietal cells of the stomach produce intrinsic factor, and following a gastrectomy, the absorption of vitamin B12 will be markedly reduced, and a deficiency state will exist.
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This question is part of the following fields:
- Gastrointestinal
- Physiology
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Question 30
Incorrect
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A 65-year-old man comes for a visit at the clinic with complaints of abdominal pain. On inquiring about drug history, you find out that he has been taking around 8-10 paracetamol to help relieve the pain.
Out of the following, which one is believed to be the main mechanism of action for paracetamol?Your Answer: Blockade of the production of thromboxane A2
Correct Answer: Selective inhibition of COX-3 receptors
Explanation:The FDA categorizes Paracetamol as an NSAID (nonsteroidal anti-inflammatory drug) as it is believed to selectively inhibit cyclo-oxygenase 3 (COX-3) receptors in the brain and spinal cord.
COX-3 is a unique variant of the more known COX-1 and COX-2. It is responsible for the production of prostaglandins in central areas, which sensitizes free nerve endings to the chemical mediators of pain. Therefore, by selectively inhibiting COX-3, paracetamol effectively reduces pain sensation by increasing the pain threshold.
Acetaminophen does not inhibit cyclooxygenase in peripheral tissues and, therefore, has no peripheral anti-inflammatory effects.
The antipyretic actions of acetaminophen are likely attributed to direct action on heat-regulating centres in the brain, resulting in peripheral vasodilation, sweating, and loss of body heat. -
This question is part of the following fields:
- CNS Pharmacology
- Pharmacology
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