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Question 1
Incorrect
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Which of the following is NOT a function of antibodies:
Your Answer: Activate the complement cascade
Correct Answer: Act as antigen receptors on T lymphocytes
Explanation:Antibodies: Neutralise toxins and prevent attachment of pathogensTarget, opsonise or agglutinate (clump together) antigens for phagocytosisActivate the complement cascade (leading to lysis or opsonisation of the pathogen)Act as antigen receptors on B lymphocytesActivate antibody-dependent cell-mediated cytotoxicity by natural killer (NK) cells or T cytotoxic cellsProvide mucosal immunity (IgA-mediated)Stimulate degranulation of mast cells (IgE and IgG mediated)Provide passive immunity to the newborn (through transplacental passage of IgG and secretion of IgA in breast milk)
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This question is part of the following fields:
- Immune Responses
- Pathology
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Question 2
Incorrect
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Which lobe of the prostate gland is most commonly affected in benign prostatic hypertrophy?
Your Answer: Anterior
Correct Answer: Median
Explanation:Benign enlargement of the prostate is common in men older than 50 years. The cause is possibly an imbalance in the hormonal control of the gland. The median lobe of the gland enlarges upward and encroaches within the sphincter vesicae, located at the neck of the bladder. The leakage of urine into the prostatic urethra causes an intense reflex desire to micturate. The enlargement of the median and lateral lobes of the gland produces elongation and lateral compression and distortion of the urethra so that the patient experiences difficulty in passing urine and the stream is weak. Back-pressure effects on the ureters and both kidneys are a common complication. The enlargement of the uvula vesicae (owing to the enlarged median lobe) results in the formation of a pouch of stagnant urine behind the urethral orifice within the bladder. The stagnant urine frequently becomes infected, and the inflamed bladder (cystitis) adds to the patient’s symptoms.In all operations on the prostate, the surgeon regards the prostatic venous plexus with respect. The veins have thin walls, are valveless, and are drained by several large trunks directly into the internal iliac veins. Damage to these veins can result in a severe haemorrhage.
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This question is part of the following fields:
- Abdomen And Pelvis
- Anatomy
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Question 3
Incorrect
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You come across a 60-year-old woman with a history of chronic pancreatitis. Today she is complaining of epigastric pain. She has blood tests done especially to review her cholecystokinin levels.Which of the following is a cholecystokinin (CCK) releasing site?Â
Your Answer: C-cells in the upper small intestine
Correct Answer: I-cells in the upper small intestine
Explanation:The I-cells in the duodenum generate and release cholecystokinin (CCK), a peptide hormone. It has a crucial role in the digestion process as a hormonal regulator.CCK cells are concentrated in the proximal small intestine, and when food is consumed, the hormone is produced into the bloodstream. The presence of partly digested lipids and proteins in the duodenum is one of the most powerful stimulus for CCK synthesis.CCK’s key physiological effects include:Encourages the pancreas to release digesting enzymes into the small intestine.Stimulates gallbladder contraction and sphincter of Oddi relaxation, resulting in bile delivery into the duodenum.Gastric emptying is inhibited, and gastric acid output is reduced.Satiety induction is a process that involves inducing a feeling of fullness.
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This question is part of the following fields:
- Gastrointestinal Physiology
- Physiology
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Question 4
Incorrect
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You've been summoned to the resuscitation area to assist a patient who is having a seizure. As part of the treatment protocol, a benzodiazepine dose is given.Which of the following statements about the use of benzodiazepines in seizures is correct?
Your Answer: Benzodiazepines have low lipid solubility
Correct Answer: Lorazepam can be given by the rectal route
Explanation:A single dose of IV benzodiazepine will terminate the seizure in 60 to 80 percent of patients who present with seizures.Because benzodiazepines are lipid-soluble, they cross the blood-brain barrier quickly. This explains their quick onset of action.As a first-line treatment, IV lorazepam should be given. If IV lorazepam is not available, IV diazepam can be used instead, and buccal midazolam can be used if intravenous access cannot be established quickly. Lorazepam can be administered via the rectal route, but it is less reliable and has a lower absorption rate and bioavailability.
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This question is part of the following fields:
- CNS Pharmacology
- Pharmacology
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Question 5
Incorrect
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Which of the following statements regarding the infectivity periods of these corresponding diseases is correct?
Your Answer: Chickenpox is infectious from 2 days before the rash appears
Correct Answer: Rubella is infectious until 5 days after the rash appears
Explanation:Rubella can be contagious from 7 days before to 7 days after the rash appears.Patients with measles are contagious from 1-2 days before the onset of symptoms.A person with chickenpox is considered contagious beginning 1 to 2 days before rash onset until all the chickenpox lesions have crusted (scabbed). The infectious period of mumps is considered from 2 days before to 5 days after parotitis onset.Hepatitis A is highly transmissible and has an average incubation period of 28 to 30 days (range 15–50 days). The maximum infectivity is during the second half of the incubation period (i.e. while asymptomatic) and most cases are considered non-infectious after the first week of jaundice.
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This question is part of the following fields:
- Microbiology
- Specific Pathogen Groups
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Question 6
Correct
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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 iodineBlockage of the Sino-atrial heart valve (except in cardiac arrest)Bradycardia in the sinuses (except in cardiac arrest)Thyroid disorders
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This question is part of the following fields:
- Cardiovascular Pharmacology
- Pharmacology
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Question 7
Correct
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A 25 year old man presents to the emergency room with abdominal pain, vomiting and constipation. A CT scan is done which is suggestive of Meckel's diverticulum. Where does the blood supply of the Meckel's diverticulum originate?
Your Answer: Superior mesenteric artery
Explanation:Meckel’s diverticulum has certain classic characteristics.1. It lies on the antimesenteric border of the middle-to-distal ileum2. It is approximately 2 feet proximal to the ileocaecal junction3. It appears as a blind-ended tubular outpouching of bowel4. It is about 2 inches long, 5. It occurs in about 2% of the population, 6. It may contain two types of ectopic tissue (gastric and pancreatic). 7. The diverticulum is supplied by the superior mesenteric artery.8. Proximal to the major duodenal papilla the duodenum is supplied by the gastroduodenal artery (branch of the coeliac trunk)9. Distal to the major duodenal papilla it is supplied by the inferior pancreaticoduodenal artery (branch of superior mesenteric artery).10. The arterial supply to the jejunoileum is from the superior mesenteric artery.
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This question is part of the following fields:
- Abdomen
- Anatomy
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Question 8
Incorrect
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Regarding antimuscarinic antispasmodics, which of the following statements is CORRECT:
Your Answer: Hyoscine butylbromide is a very effective antispasmodic.
Correct Answer: They are contraindicated in paralytic ileus.
Explanation:Antimuscarinics are contraindicated in paralytic ileus. Antimuscarinics reduce intestinal motility by blocking muscarinic acetylcholine receptors and relaxing smooth muscle. Hyoscine butylbromide is advocated as a gastrointestinal antispasmodic, but it is poorly absorbed and thus has limited clinical utility. Antimuscarinics cause a reduction in bronchial secretions (they can be used to this effect in palliative patients). Antispasmodics are occasionally of value in treating abdominal cramp associated with diarrhoea but they should not be used for primary treatment. Antispasmodics should be avoided in young children with gastroenteritis because they are rarely effective and have troublesome side effects.
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This question is part of the following fields:
- Gastrointestinal
- Pharmacology
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Question 9
Incorrect
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Regarding penicillin antibiotics, which of the following statements is CORRECT:
Your Answer: Patients who only develop a rash or urticaria immediately after penicillin should not be noted as having a penicillin allergy.
Correct Answer: Patients with a history of atopy are at higher risk of hypersensitivity reactions.
Explanation:Allergic reactions to penicillins occur in 1 – 10% of exposed individuals; anaphylactic reactions occur in fewer than 0.05% of treated patients. Patients with a history of atopic allergy are at higher risk of anaphylactic reactions to penicillins. Patients with a history of anaphylaxis, urticaria, or rash immediately after penicillin use should not receive a penicillin or other beta-lactam antibiotics; about 0.5 – 6.5 % of penicillin-sensitive patients will also be allergic to the cephalosporins. Patients with a history of a more minor rash (i.e. non-confluent, non-pruritic rash restricted to a small area of the body) or delayed reaction (rash occurring more than 72 hours after penicillin administration), may not be truly allergic and may be considered for penicillin or beta-lactam treatment in severe infection (although possibility of allergy should be borne in mind). Other beta-lactam antibiotics (including cephalosporins) can be used in these patients.
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This question is part of the following fields:
- Infections
- Pharmacology
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Question 10
Correct
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A 34-year-old man presents with loss of vision in his left eye due to an episode of optic neuritis. Upon history taking, it was noted that he has a history of multiple sclerosis. Which of the following anatomical points in the visual pathway has the lesion occurred?
Your Answer: Optic nerve
Explanation:A lesion in the optic nerve causes ipsilateral monocular visual loss.Optic neuritis is an inflammatory demyelination of the optic nerve that is highly associated with multiple sclerosis. The two most common symptoms of optic neuritis are vision loss and eye pain.
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This question is part of the following fields:
- Anatomy
- Central Nervous System
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Question 11
Correct
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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: 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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Question 12
Correct
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If the afferent arteriole's diameter is smaller than the efferent arteriole's diameter in the glomerulus:
Your Answer: The net filtration pressure will decrease
Explanation:The relative resistance of the afferent and efferent arterioles substantially influences glomerular capillary hydrostatic pressure and consequently GFR. Filtration is forced through the filtration barrier due to high pressure in the glomerular capillaries. Afferent arteriolar constriction lowers this pressure while efferent arteriolar constriction raises it.
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This question is part of the following fields:
- Physiology
- Renal
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Question 13
Correct
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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: 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 caseThyroid ultrasound scan – is a cost-effective and safe alternative to the radioactive iodine uptake scan.
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This question is part of the following fields:
- Endocrine Physiology
- Physiology
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Question 14
Correct
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Regarding the lacrimal apparatus, which of the following statements is CORRECT:
Your Answer: Lacrimal fluid is drained from the eyeball through the lacrimal punctum.
Explanation:Lacrimal fluid is drained from the eyeball through the lacrimal punctum.
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This question is part of the following fields:
- Anatomy
- Head And Neck
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Question 15
Incorrect
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You see a 30-year-old man who has come to the department with a very tender right elbow. On examination, the elbow is very hot and red, and appears to be acutely inflamed.Which SINGLE statement regarding acute inflammation is FALSE?
Your Answer: Margination occurs when neutrophils flow nearer the vessel wall rather than in the axial stream
Correct Answer: Reduced extravascular osmotic pressure leads to oedema
Explanation:Inflammation can be divided intoacute inflammation, which occurs over seconds, minutes, hours, and days, andchronic inflammation, which occurs over longer periods.Acute inflammationcommences within seconds or minutes following the injury of tissues. There are numerous potential stimuli for an acute inflammatory response including infections (bacterial, viral, fungal, parasitic), tissue necrosis, foreign bodies, and Immune reactions (hypersensitivity reactions). The chief cell type of acute inflammation is the neutrophil.There are three main processesthat occur in the acute inflammatory response:Increased blood flowIncreased capillary permeabilityNeutrophil migration1. Increased blood flow:Vasoactive mediators are released, such as nitric oxide, histamine, bradykinins, and prostaglandin E2. These mediators cause vasodilatation and increased blood flow to the area (causing redness and heat).2. Increased capillary permeability:The vasoactive mediators also cause increased capillary permeability by causing endothelial cell contraction that widens the intercellular gaps of venules. This allows an outpouring of protein-rich fluid (exudate) into the extracellular tissues that results in a reduction of intravascular osmotic pressure and an increase in extravascular/interstitial pressure. The increased interstitial osmotic pressure leads to oedema.3. Neutrophil migration:Neutrophils leave the vasculature through the following sequence of events:Margination and rolling: neutrophils flow nearer the vessel wall, rather than in the axial stream, which is referred to as margination. Following margination the neutrophils begin rolling along the surface of the vascular endothelium.Activation and adhesion: then as a result of interaction with endothelial cell adhesion molecules (CAMs) that is mediated by selectins, the neutrophils are activated and adhere to the endothelium.Transmigration: once bound to the endothelium, neutrophils squeeze through gaps between adjacent endothelial cells into the interstitial fluid, in a process calleddiapedesis.
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This question is part of the following fields:
- General Pathology
- Pathology
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Question 16
Incorrect
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Which of the following organelles form lysosomes?
Your Answer: The ribosomes
Correct Answer: The Golgi apparatus
Explanation:Lysosomes are formed by the Golgi apparatus or the endoplasmic reticulum. Lysosome releases its enzymes and digests the cell when the cell dies.
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This question is part of the following fields:
- Basic Cellular Physiology
- Physiology
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Question 17
Incorrect
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Which of the following statements is correct regarding the neuronal action potential?
Your Answer: The membrane threshold potential is usually around +20 mV.
Correct Answer: Initial depolarisation occurs as a result of a Na + influx.
Explanation:The resting potential in most neurons has a value of approximately -70 mV. The threshold potential is generally around -55 mV. Initial depolarisation when there is Na+influx through ligand-gated Na+channels. Action potential is an all or nothing response. The size of the action potential is constant and so, the intensity of the stimulus is coded by the frequency of firing of a neuron. K+efflux is responsible for repolarisation.
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This question is part of the following fields:
- Basic Cellular
- Physiology
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Question 18
Correct
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Approximately what proportion of lymphocytes are B-cells:
Your Answer: 0.2
Explanation:B-cells (20% of lymphocytes) mature in the bone marrow and circulate in the peripheral blood until they undergo recognition of antigen. B-cell immunoglobulin molecules synthesised in the cell are exported and bound to the surface membrane to become the B-cell receptor (BCR) which can recognise and bind to a specific antigen (either free or presented by APCs). The BCR is also important for antigen internalisation, processing and presentation to T helper cells. Most antibody responses require help from antigen-specific T helper cells (although some antigens such as polysaccharide can lead to T-cell independent B-cell antibody production). When the B-cell is activated, the receptor itself is secreted as free soluble immunoglobulin and the B-cell matures into a memory B-cell or a plasma cell (a B-cell in its high-rate immunoglobulin secreting state). Plasma cells are non-motile and are found predominantly in the bone marrow or spleen. Most plasma cells are short-lived (1 – 2 weeks) but some may survive much longer. A proportion of B-cells persist as memory cells, whose increased number and rapid response underlies the augmented secondary response of the adaptive immune system.
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This question is part of the following fields:
- Immune Responses
- Pathology
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Question 19
Incorrect
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Which of the following conditions manifests hyperkalaemia as one of its symptoms?
Your Answer: Type 1 renal tubular acidosis
Correct Answer: Congenital adrenal hyperplasia
Explanation:Plasma potassium greater than 5.5 mmol/L is hyperkalaemia or elevated plasma potassium level. Among the causes of hyperkalaemia include congenital adrenal hyperplasia. Congenital adrenal hyperplasia is a general term referring to autosomal recessive disorders involving a deficiency of an enzyme needed in cortisol and/or aldosterone synthesis. The level of cortisol and/or aldosterone deficiency affects the clinical manifestations of congenital adrenal hyperplasia. When it involves hypoaldosteronism, it can result in hyponatremia and hyperkalaemia. While hypercortisolism can cause hypoglycaemia.The other causes of hyperkalaemia may include renal failure, excess potassium supplementation, Addison’s disease (adrenal insufficiency), renal tubular acidosis (type 4), rhabdomyolysis, burns, trauma, Tumour lysis syndrome, acidosis, and medications such as ACE inhibitors, angiotensin receptor blockers, NSAIDs, beta-blockers, digoxin, and suxamethonium. Bartter’s syndrome is characterized by hypokalaemic alkalosis with normal to low blood pressure. Type 1 and 2 renal tubular acidosis both cause hypokalaemia. Gitelman’s syndrome is a defect of the distal convoluted tubule of the kidney. It causes metabolic alkalosis with hypokalaemia and hypomagnesemia. And excessive liquorice ingestion causes hypermineralocorticoidism and hypokalaemia as well. Thus, among the choices, only congenital adrenal hyperplasia can cause hyperkalaemia.
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This question is part of the following fields:
- Physiology
- Renal Physiology
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Question 20
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 21
Incorrect
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Aplastic crises in sickle cell anaemia is classically precipitated by which of the following infections:
Your Answer: Coxsackie B
Correct Answer: Parvovirus B19
Explanation:A serious complication in sickle cell disease (SCD) is the aplastic crisis. This may be caused by infection with Parvovirus B-19 (B19V). This virus causes fifth disease, a normally benign childhood disorder associated with fever, malaise, and a mild rash. This virus infects RBC progenitors in bone marrow, resulting in impaired cell division for a few days. Healthy people experience, at most, a slight drop in hematocrit, since the half-life of normal erythrocytes in the circulation is 40-60 days. In people with SCD, however, the RBC lifespan is greatly shortened (usually 10-20 days), and a very rapid drop in Hb occurs. The condition is self-limited, with bone marrow recovery occurring in 7-10 days, followed by brisk reticulocytosis.
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This question is part of the following fields:
- Haematology
- Pathology
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Question 22
Correct
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Regarding myeloma, which of the following statements is CORRECT:
Your Answer: Myeloma is associated with marked rouleaux formation on blood film.
Explanation:98% of cases of myeloma occur over the age of 40 years with a peak incidence between 65 and 70 years. The disease is twice as common in black individuals compared to those of white or Asian origin. Laboratory findings include presence of a paraprotein in serum/urine (the paraprotein is IgG in 60% of cases, IgA in 20% and light chain only in almost all the rest) and marked Rouleaux formation on blood film. There is no cure for myeloma. The overall median survival is now 7-10 years and in younger (less than 50 years) patients it can be over 10 years.
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This question is part of the following fields:
- Haematology
- Pathology
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Question 23
Correct
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Digoxin is contraindicated in all of the following EXCEPT for:
Your Answer: Asthma
Explanation:Digoxin is contraindicated in:Supraventricular arrhythmias associated with accessory conduction pathways e.g. Wolff-Parkinson-White syndromeVentricular tachycardia or fibrillationHeart conduction problems e.g. second degree or intermittent complete heart blockHypertrophic cardiomyopathy (unless concomitant atrial fibrillation and heart failure but should be used with caution)
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This question is part of the following fields:
- Cardiovascular
- Pharmacology
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Question 24
Correct
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Injury to which nerve can lead to weakness or paralysis of the brachialis muscle?
Your Answer: The musculocutaneous nerve
Explanation:The brachialis muscle is a prime flexor of the forearm at the elbow joint. It is fusiform in shape and located in the anterior (flexor) compartment of the arm, deep to the biceps brachii. The brachialis is a broad muscle, with its broadest part located in the middle rather than at either of its extremities. It is sometimes divided into two parts, and may fuse with the fibres of the biceps brachii, coracobrachialis, or pronator teres muscles. It also functions to form part of the floor of the cubital fossa.The brachialis is primarily supplied by the musculocutaneous nerve (C5, C6). In addition, a small lateral portion of the muscle is innervated by the radial nerve (C7).
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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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An 11-year-old presented to a GP with a history of headache, neck stiffness and photophobia. On examination, HR is 122, BP is 87/42, RR is 28, SaO 2 is 95%, temperature is 39.4 o C. There is a recent petechial rash on legs and arms. The GP administered a dose of antibiotics in the prehospital setting before transferring to the Emergency Department.Which of these would the GP have administered?
Your Answer: IM benzylpenicillin 600 mg
Correct Answer: IM benzylpenicillin 1.2 g
Explanation:General Practitioners are advised to give a single injection of benzylpenicillin by intravenous or intramuscular injection before transferring the patient urgently to the ED when bacterial meningitis is suspected.The recommended doses are:Infants under 1 year: 300 mgChildren ages 1 to 9 years: 600 mgChildren aged 10 years and over: 1.2gAdults: 1.2g
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This question is part of the following fields:
- Infections
- Pharmacology
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Question 26
Incorrect
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A patient presents with a fever, headache and neck stiffness. A CSF sample of someone with meningococcal meningitis typically shows:
Your Answer: Gram-negative diplococci
Correct Answer: All of the above
Explanation:CSF analysis typically shows: cloudy turbid appearanceraised WCC – predominantly neutrophilshigh proteinlow glucose (typically < 40% of serum glucose)Gram-negative diplococci seen under microscopy
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This question is part of the following fields:
- Microbiology
- Pathogens
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Question 27
Incorrect
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Which of the following local anaesthetics has the longest duration of action:
Your Answer: Lidocaine
Correct 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.
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This question is part of the following fields:
- Anaesthesia
- Pharmacology
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Question 28
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 29
Incorrect
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A 60-year-old man diagnosed with chronic kidney disease has an elevated creatinine level and a reduced glomerular filtration rate (GFR).Which statement concerning glomerular filtration is true?
Your Answer: The GFR declines with age after the age of 40 at a rate of approximately 5 ml/min/year
Correct Answer: Creatinine is freely filtered at the glomerulus
Explanation:Glomerular filtration is a passive process. It depends on the net hydrostatic pressure across the glomerular capillaries, the oncotic pressure, and the intrinsic permeability of the glomerulus.The mean values for glomerular filtration rate (GFR) in young adults are 130 ml/min/1.73m2 in males and 120 ml/min/1.73m2in females.The GFR declines with age after the age of 40 at a rate of approximately 1 ml/min/year.The Cockcroft and Gault formula overestimates creatinine in obese patients. This is because their endogenous creatinine production is less than that predicted by overall body weight.Creatinine is used in the estimation of GFR because it is naturally produced by muscle breakdown, not toxic, not produced by the kidney, freely filtered at the glomerulus, not reabsorbed from the nephron, and does not alter GFR.
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This question is part of the following fields:
- Physiology
- Renal Physiology
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Question 30
Incorrect
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A 24-year-old student with red and painful right eye presents. Conjunctival erythema, mucopurulent discharge and lid crusting are seen on examination, and patient denies presence of itching of the eye. All his observations are normal, he has no fever and is otherwise well.Which of these is the most likely causative organism?
Your Answer: Staphylococcus epidermidis
Correct Answer: Haemophilus influenzae
Explanation:The most frequent cause of red eye is conjunctivitis. It is caused by inflammation of the conjunctiva which can be infective or allergic and accounts for about 35% of all eye problems presenting to general practice.Viral conjunctivitis is commonly caused by adenoviruses and it is the most common infectious conjunctivitis.The common bacterial causes of conjunctivitis are Haemophilus influenzae, Streptococcus pneumoniae, and Staphylococcus aureus.The clinical features of infective conjunctivitis include:Acute onset of conjunctival erythemaFeeling ‘grittiness’, ‘foreign body’ or ‘burning’ sensation in the eye.Watering and discharge which may cause transient blurring of visionThe discharge for viral conjunctivitis is less than that of bacterial conjunctivitis and usually watery.
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This question is part of the following fields:
- Microbiology
- Specific Pathogen Groups
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SESSION STATS - PERFORMANCE PER SPECIALTY
