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Question 1
Correct
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A patient noticed ankle swelling and has passed very little urine over the past 24 hours. He also has nausea and vomiting, reduced urine output and his blood results reveal a sudden rise in his creatinine levels over the past 48 hours. You make a diagnosis of acute kidney injury (AKI).Which one of these is a prerenal cause of AKI?
Your Answer: Cardiac failure
Explanation:The causes of AKI can be divided into pre-renal, intrinsic renal and post-renal causes. Majority of AKI developing in the community is due to a pre-renal causes (90% of cases).Pre-renal causes: Haemorrhage, severe vomiting or diarrhoea, burns, cardiac failure, liver cirrhosis, nephrotic syndrome, hypotension, severe cardiac failure, NSAIDs, COX-2 inhibitors, ACE inhibitors or ARBs, Abdominal aortic aneurysm, renal artery stenosis, hepatorenal syndrome, Intrinsic (renal) causes:Eclampsia, glomerulonephritis, thrombosis, haemolytic-uraemic syndrome, acute tubular necrosis (ATN), acute interstitial nephritis, drugs ( NSAIDs), infection or autoimmune diseases, vasculitis, polyarteritis nodosa, thrombotic microangiopathy, cholesterol emboli, renal vein thrombosis, malignant hypertensionPost-renal causes: Renal stones, Blood clot, Papillary necrosis, Urethral stricture, Prostatic hypertrophy or malignancy, Bladder tumour, Radiation fibrosis, Pelvic malignancy, Retroperitoneal fibrosis
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This question is part of the following fields:
- General Pathology
- Pathology
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Question 2
Incorrect
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Which of the following best describes the main sites of constriction of the ureters:
Your Answer: At the ureteropelvic junction and where the ureter is crossed by the ductus deferens
Correct Answer: At the ureteropelvic junction, at the pelvic brim and where the ureters enter the bladder
Explanation:At three points along their course, the ureters are constricted denoting the most likely areas for renal calculi to lodge:the first point is at the ureteropelvic junction (where the renal pelvis becomes continuous with the ureter)the second point is where the ureter crosses the common iliac vessels at the pelvic brimthe third point is at the vesicoureteric junction (where the ureter enters the wall of the bladder)
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This question is part of the following fields:
- Abdomen
- Anatomy
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Question 3
Correct
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A lesion to which part of the optic radiation will result in contralateral homonymous inferior quadrantanopia?
Your 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.
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This question is part of the following fields:
- Anatomy
- Central Nervous System
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Question 4
Correct
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Regarding the lumbar plexus, which of the following is a direct muscular branch?
Your Answer: Nerve to quadratus lumborum
Explanation:The lumbar plexus gives rise to several branches which supply various muscles and regions of the posterior abdominal wall and lower limb. These branches include the Iliohypogastric, ilioinguinal, genitofemoral, lateral femoral cutaneous, femoral and obturator nerves.In addition, the lumbar plexus gives off muscular branches from its roots, a branch to the lumbosacral trunk and occasionally an accessory obturator nerve.
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This question is part of the following fields:
- Anatomy
- Lower Limb
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Question 5
Correct
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Polyuria and polydipsia develop in a patient with a history of affective disorders illness who has been on long-term lithium. She has a fluid deprivation test because she is suspected of having nephrogenic diabetic insipidus.Which of the following urine osmolality findings would be the most reliable in confirming the diagnosis?Â
Your Answer: After fluid deprivation <300 mosmol/kg, after IM desmopressin <300 mosmol/kg
Explanation:The inability to produce concentrated urine is a symptom of diabetes insipidus. Excessive thirst, polyuria, and polydipsia are all symptoms of this condition. There are two forms of diabetes insipidus: Nephrogenic diabetes insipidus and cranial (central) diabetes insipidus.A lack of ADH causes cranial diabetic insipidus. Patients with cranial diabetes insipidus can have a urine output of up to 10-15 litres per 24 hours, however most patients can maintain normonatraemia with proper fluid consumption. Thirty percent of cases are idiopathic, while another thirty percent are caused by head injuries. Neurosurgery, brain tumours, meningitis, granulomatous disease (e.g. sarcoidosis), and medicines like naloxone and phenytoin are among the other reasons. There is also a very rare hereditary type that is linked to diabetes, optic atrophy, nerve deafness, and bladder atonia.Renal resistance to the action of ADH causes nephrogenic diabetes insipidus. Urine output is significantly increased, as it is in cranial diabetes insipidus. Secondary polydipsia can keep serum sodium levels stable or raise them. Chronic renal dysfunction, metabolic diseases (e.g., hypercalcaemia and hypokalaemia), and medications, such as long-term lithium use and demeclocycline, are all causes of nephrogenic diabetes insipidus.The best test to establish if a patient has diabetes insipidus vs another cause of polydipsia is the water deprivation test, commonly known as the fluid deprivation test. It also aids in the distinction between cranial and nephrogenic diabetes insipidus. Weight, urine volume, urine osmolality, and serum osmolality are all measured after patients are denied water for up to 8 hours. At the end of the 8-hour period, 2 micrograms of IM desmopressin is given, and measures are taken again at 16 hours.The following are the way results are interpreted:Urine osmolality after fluid deprivation : Urine osmolality after IM desmopressinCranial diabetes insipidus800 mosmol/kgNephrogenic diabetes insipidus<300 mosmol/kg : 800 mosmol/kg : >800 mosmol/kg
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This question is part of the following fields:
- Physiology
- Renal Physiology
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Question 6
Correct
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Salbutamol should be used with caution in patients with which of the following:
Your Answer: Susceptibility to QT-interval prolongation
Explanation:Beta-2 agonists should be used with caution in people with: Cardiovascular disease, including arrhythmias and hypertension (beta-2 agonists may cause an increased risk of arrhythmias and significant changes to blood pressure and heart rate)Diabetes(risk of hyperglycaemia and ketoacidosis, especially with intravenous use)Hyperthyroidism(beta-2 agonists may stimulate thyroid activity)Hypokalaemia(potentially serious hypokalaemia may result from beta-2 agonist therapy; this effect may be potentiated in severe asthma by concomitant treatment with theophylline, corticosteroids, diuretics and by hypoxia)Susceptibility to QT-interval prolongationConvulsive disorders
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This question is part of the following fields:
- Pharmacology
- Respiratory
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Question 7
Incorrect
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Aplastic crises in sickle cell anaemia is classically precipitated by which of the following infections:
Your Answer: Cytomegalovirus
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 8
Correct
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Discontinuous capillaries are typically found where in the body:
Your Answer: Reticuloendothelial system
Explanation:Discontinuous capillaries, found in the reticuloendothelial system (bone marrow, liver and spleen), have large gaps between endothelial cells and are permeable to red blood cells.
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This question is part of the following fields:
- Cardiovascular
- Physiology
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Question 9
Correct
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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: Sodium channel blocker
Explanation:Phenytoin is in the anticonvulsants class of drugs and is used in the management and treatment of the following:1. epilepsy2. generalized tonic-clonic seizures3. complex partial seizures4. 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 10
Correct
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Bordetella pertussis is spread via which of the following routes:
Your Answer: Respiratory droplet route
Explanation:Bordetella pertussis is a Gram negative coccobacillus that causes whooping cough. B. pertussis is spread via the respiratory droplet route and expresses fimbriae that aid their adhesion to the ciliated epithelium of the upper respiratory tract, and produce a number of exotoxins, causing the characteristic thickened bronchial secretions, paralysis of cilia and lymphocytosis.
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This question is part of the following fields:
- Microbiology
- Pathogens
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Question 11
Correct
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Carbamazepine is contraindicated in which of the following:
Your Answer: Atrioventricular block
Explanation:Carbamazepine is contraindicated in:- People with known hypersensitivity to carbamazepine or structurally related drugs- People with atrioventricular block (may suppress AV conduction and ventricular automaticity)- People with a history of bone marrow depression (risk of agranulocytosis and aplastic anaemia)- People with a history of acute porphyrias- People taking a monoamine oxidase inhibitor (risk of serotonin syndrome)
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This question is part of the following fields:
- Central Nervous System
- Pharmacology
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Question 12
Correct
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Mannitol is primarily indicated for which of the following:
Your Answer: Cerebral oedema
Explanation:Mannitol is an osmotic diuretic that can be used to treat cerebral oedema and raised intraocular pressure. Mannitol is a low molecular weight compound and is, therefore, freely filtered at the glomerulus and is not reabsorbed. It, therefore, increases the osmolality of the glomerular filtrate and tubular fluid, increasing urinary volume by an osmotic effect. It also does not cross the blood-brain-barrier (BBB).
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This question is part of the following fields:
- Cardiovascular
- Pharmacology
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Question 13
Correct
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A 40-year-old woman presents with a red, scaly, itchy rash around her navel that occurred after contact with a nickel belt buckle. A diagnosis of allergic contact dermatitis is made. Which type of hypersensitivity reaction is this?
Your Answer: Type IV hypersensitivity reaction
Explanation:A type IV hypersensitivity reaction occurred in this patient. Allergic contact dermatitis is an inflammatory skin reaction occurring in response to an external stimulus, acting either as an allergen or an irritant, caused by a type IV or delayed hypersensitivity reaction. They usually take several days to develop.
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This question is part of the following fields:
- General Pathology
- Pathology
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Question 14
Incorrect
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One of these statements about cohort studies is true:
Your Answer: They are usually shorter in duration than case-control studies
Correct Answer: They are longitudinal in nature
Explanation:A cohort study is a longitudinal, observational study. It follows a group of patients (the cohort) forward in time and monitors the effects of the aetiological factor under study upon them.Cohort studies are usually of longer duration and are more expensive than case-control studies. They, however, provide more useful and reliable information.Cohort studies follow a cohort of patients who don’t have a disease and evaluate the absolute and relative risk of contracting the disease after exposure to the aetiological agent.Cross-sectional studies are the best way to determine the prevalence of a disease. while Cohort studies are better at determining the incidence of a 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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How does an action potential in the motor end plate rapidly spread to the central portions of the muscle cells?
Your Answer: Z-lines
Correct Answer: Transverse tubules
Explanation:When the concentration of intracellular Ca2+rises, muscle contraction occurs. The pathway of an action potential is down tube-shaped invaginations of the sarcolemma called T-tubules (transverse tubules). These penetrate throughout the muscle fibre and lie adjacent to the terminal cisternae of the sarcoplasmic reticulum. The voltage changes in the T-tubules result in the opening of sarcoplasmic reticulum Ca2+channels and there is there is release of stored Ca2+into the sarcoplasm. Thus muscle contraction occurs via excitation-contraction coupling (ECC) mechanism.
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This question is part of the following fields:
- Basic Cellular
- Physiology
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Question 16
Correct
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Question 17
Correct
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Gastrin primarily acts to perform which of the following functions:
Your Answer: Stimulate gastric acid secretion
Explanation:Gastrin primarily  acts to stimulate acid secretion from parietal cells (both directly and indirectly by stimulating release of histamine from ECL cells).
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This question is part of the following fields:
- Gastrointestinal
- Physiology
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Question 18
Correct
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An 80-year-old male has presented with chest pain characteristic of angina pectoris. Before initiating treatment with Glyceryl nitrate, you examine the patient and find a murmur. The patient reveals that he has a heart valve disorder, and you immediately put a hold on the GTN order.Which of the following valve disorders is an absolute contraindication to the use of GTN?
Your Answer: Mitral stenosis
Explanation:Angina pectoris is the most common symptom of ischemic heart disease and presents with chest pain relieved by rest and nitro-glycerine. Nitrates are the first-line treatment to relieve chest pain caused by angina. The commonly used nitrates are: 1. Nitro-glycerine (NTG) – angina pectoris (treatment/prophylaxis), acute coronary syndrome, heart failure, hypertension2. Isosorbide mononitrate (ISMN) – chronic angina pectoris (treatment)3. Isosorbide dinitrate (ISDN) – angina pectoris (treatment/prophylaxis)The nitrate drugs cause vasodilation via the action of nitric oxide. The contraindications to the use of nitrate are the following: 1. Allergy to nitrates2. Concomitant use of phosphodiesterases (PDE) inhibitors such as tadalafil and sildenafil3. Right ventricular infarction4. Hypertrophic cardiomyopathy5. Cardiac tamponade6. Constrictive pericarditis7. Hypotensive conditions8. Hypovolaemia9. Marked anaemia10. Mitral stenosis11. Raised intracranial pressure due to cerebral haemorrhage or head trauma12. Toxic pulmonary oedema
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This question is part of the following fields:
- Cardiovascular Pharmacology
- Pharmacology
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Question 19
Incorrect
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All of the following statements are considered true regarding randomized control trials, except:
Your Answer: They can overcome small sample sizes
Correct Answer: They can eliminate the need for further studies
Explanation:Meta-analysis is a quantitative, formal, epidemiological study design used to systematically assess previous research studies to derive conclusions about that body of research. Outcomes from a meta-analysis may include a more precise estimate of the effect of treatment or risk factor for disease, or other outcomes, than any individual study contributing to the pooled analysis. The examination of variability or heterogeneity in study results is also a critical outcome.The benefits of meta-analysis include a consolidated and quantitative review of a large, and often complex, sometimes apparently conflicting, body of literature. The specification of the outcome and hypotheses that are tested is critical to the conduct of meta-analyses, as is a sensitive literature search.Important medical questions are typically studied more than once, often by different research teams in different locations. In many instances, the results of these multiple small studies of an issue are diverse and conflicting, which makes the clinical decision-making difficult. The need to arrive at decisions affecting clinical practise fostered the momentum toward evidence-based medicine. Evidence-based medicine may be defined as the systematic, quantitative, preferentially experimental approach to obtaining and using medical information. Therefore, meta-analysis, a statistical procedure that integrates the results of several independent studies, plays a central role in evidence-based medicine.
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This question is part of the following fields:
- Evidence Based Medicine
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Question 20
Correct
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Regarding oral rehydration therapy, which of the following statements is INCORRECT:
Your Answer: Oral rehydration solutions should be slightly hyperosmolar.
Explanation:Oral rehydration therapy (ORT) is a fluid replacement strategy used to prevent or treat dehydration. It is less invasive than other strategies for fluid replacement and has successfully lowered the mortality rate of diarrhoea in developing countries. Oral rehydration solutions should be slightly hypo-osmolar (about 250 mmol/litre) to prevent the possible induction of osmotic diarrhoea.ORT contains glucose (e.g. 90 mmol/L in dioralyte). The addition of glucose improves sodium and water absorption in the bowel and prevents hypoglycaemia. It also contains essential mineral salts.Current NICE guidance recommends that 50 ml/kg is given over 4 hours for the treatment of mild dehydration.Once rehydrated, a child should continue with their usual daily fluid intake plus 200 ml ORT after each loose stool. In an infant, give ORT at 1-1.5 x the normal feed volume and in an adult, give 200-400 ml after each loose stool.
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This question is part of the following fields:
- Fluids And Electrolytes
- Pharmacology
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Question 21
Correct
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A 54-year-old man returns from a recently holiday on a cruise ship with a dry cough and a fever. Today he has also had several episodes of diarrhoea and has developed bilateral pleuritic chest pain. He states that he is short of breath, most notably on exertion. He had been prescribed amoxicillin by the cruise ship doctor a few days earlier but has not seen any improvement.Which of the following is the most likely causative organism? Select ONE answer only.
Your Answer: Legionella pneumophila
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 daysCough (usually non-productive and occurs in approximately 90%)Pleuritic chest painHaemoptysisHeadacheNausea, vomiting and diarrhoeaAnorexiaLegionella 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.
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This question is part of the following fields:
- Microbiology
- Specific Pathogen Groups
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Question 22
Correct
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Which one these is an example of a cause of an exudate?
Your Answer: Subphrenic abscess
Explanation:An exudate is an inflammatory fluid emanating from the intravascular space due to changes in the permeability of the surrounding microcirculation.Some common causes of exudates are: pneumonia, empyema, lung cancer, breast cancer, cancer of the pleura, SLE, rheumatoid arthritis, pericarditis, subphrenic abscess, chylothorax.Myxoedema, nephrotic syndrome, congestive cardiac failure, and liver cirrhosis all cause TRANSUDATE.
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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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Which of the following factors decreases insulin secretion:
Your Answer: Increasing blood glucose
Correct Answer: Catecholamines
Explanation:Factors that increase insulin secretion:↑ Blood glucose↑ Amino acids↑ Fatty acidsGlucagonSecretinAcetylcholineFactors that decrease insulin secretion:↓ Blood glucoseSomatostatinCatecholamines
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This question is part of the following fields:
- Endocrine
- Physiology
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Question 24
Correct
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The most common complication of paracetamol overdose is:
Your Answer: Hepatic failure
Explanation:The maximum daily dose of paracetamol in an adult is 4 grams. Doses greater than this can lead to hepatotoxicity and, less frequently, acute kidney injury. Early symptoms of paracetamol toxicity include nausea, vomiting, and abdominal pain, and usually settle within 24 hours. Symptoms of liver damage include right subcostal pain and tenderness, and this peaks 3 to 4 days after paracetamol ingestion. Other signs of hepatic toxicity include encephalopathy, bleeding, hypoglycaemia, and cerebral oedema.
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This question is part of the following fields:
- Central Nervous System
- Pharmacology
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Question 25
Correct
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A 22-year-old woman is brought in by ambulance from her GP surgery with suspected meningitis. She has been given a dose of benzylpenicillin already.What is the mechanism of action of benzylpenicillin? Select ONE answer only.
Your Answer: Inhibition of cell wall synthesis
Explanation:Penicillins and the other ß-lactam antibiotics are bactericidal. They produce their antimicrobial action by preventing cross-linkage between the linear peptidoglycan polymer chains that make up the bacterial cell wall. They, therefore, inhibit cell wall synthesis.An overview of the different mechanisms of action of the various types of antimicrobial agents is shown below:Mechanism of actionExamplesInhibition of cell wall synthesisPenicillinsCephalosporinsVancomycinDisruption of cell membrane functionPolymyxinsNystatinAmphotericin BInhibition of protein synthesisMacrolidesAminoglycosidesTetracyclinesChloramphenicolInhibition of nucleic acid synthesisQuinolonesTrimethoprim5-nitroimidazolesRifampicinAnti-metabolic activitySulfonamidesIsoniazid
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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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Which of the following is caused by an alpha-1 antitrypsin deficiency?
Your Answer: Cystic fibrosis
Correct Answer: Early onset emphysema
Explanation:Mucus contains chemicals such as alpha-1-antitrypsin, lysozyme, and IgA that protect the airway from pathogens and damaging proteases released from dead bacteria and immune cells. Early-onset emphysema results from a genetic deficit of alpha-1-antitrypsin, which is caused by unregulated protease activity in the lungs, which results in the degradation of elastin in the alveoli.
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This question is part of the following fields:
- Physiology
- Respiratory
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Question 27
Correct
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A 1-year-old male is brought to the paediatrician by his mother due to swelling of the right knee after a minor fall. On examination, the right knee is swollen, fluctuant and tender. Ultrasound-guided aspiration reveals a massive hemarthrosis. Family history shows that his older brother also has a bleeding disorder. Which one of the following conditions does the patient most likely have?
Your Answer: Haemophilia A
Explanation:A diagnosis of Haemophilia is supported in this patient by the family history and the presence of hemarthrosis-both characteristics of Haemophilia. Haemophilia A is caused by Factor VIII deficiency, leading to impaired coagulation. This disease typically presents after six months when the child starts crawling. Von Willebrand disease presents with nosebleeds and hematomas. Idiopathic thrombocytopenic purpura presents with bruises that resemble a rash. Glucose-6-phosphate dehydrogenase (G6PD) deficiency presents with haemolytic anaemia induced by specific drugs or foods. Factor V Leiden mutation causes blood clotting rather than bleeding.
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This question is part of the following fields:
- Haematology
- Pathology
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Question 28
Correct
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Excessive gastric acid output is detected in a patient with a history of recurrent stomach ulcers. It's possible that the patient has Zollinger-Ellison syndrome.Which of the following statements about stomach acid is correct?
Your Answer: The proton pump located in the canalicular membrane is vital to its secretion
Explanation:The stomach produces gastric acid, which is a digesting fluid. The stomach secretes about 2-3 litres every day. It is involved in tissue breakdown, the conversion of pepsinogen to active pepsin, and the creation of soluble salts with calcium and iron, and has a pH range of 1.5-3.5. It also serves as an immune system by destroying microbes.The following substances are found in gastric acid:WaterAcid hydrochloridePepsinogenmucous Intrinsic factorThe parietal cells in the proximal 2/3 (body) of the stomach release gastric acid. The concentration of hydrogen ions in parietal cell secretions is 1-2 million times that of blood. Chloride is released against both a concentration and an electric gradient, and active transport is required for the parietal cell to produce acid.The following is how stomach acid is secreted:1. Gastric acid secretion is dependent on the H+/K+ ATPase (proton pump) situated in the canalicular membrane. The breakdown of water produces hydrogen ions within the parietal cell. The hydroxyl ions produced in this reaction mix quickly with carbon dioxide to generate bicarbonate ions. Carbonic anhydrase is the enzyme that catalyses this process.2. In return for chloride, bicarbonate is carried out of the basolateral membrane. The ‘alkaline tide’ occurs when bicarbonate is released into the bloodstream, resulting in a modest rise in blood pH. The parietal cell’s intracellular pH is maintained by this procedure. Conductance channels carry chloride and potassium ions into the lumen of canaliculi.3. Through the action of the proton pump, hydrogen ions are pushed out of the cell and into the lumen in exchange for potassium; potassium is thus efficiently recycled.4. The canaliculi accumulate osmotically active hydrogen ions, which creates an osmotic gradient across the membrane, allowing water to diffuse outward.
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This question is part of the following fields:
- Gastrointestinal Physiology
- Physiology
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Question 29
Correct
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Question 30
Correct
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What is the average healing time for a femoral shaft fracture under normal circumstances? Choose ONE answer.
Your Answer: 12 weeks
Explanation:The process of fracture healing occurs naturally after traumatic bone disruption and begins with haemorrhage, then progresses through Inflammatory, reparative, and remodelling stagesAverage healing times of common fractures are:Femoral shaft: 12 weeksTibia: 10 weeksPhalanges: 3 weeksMetacarpals: 4-6 weeksDistal radius: 4-6 weeksHumerus: 6-8 weeks
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This question is part of the following fields:
- General Pathology
- Pathology
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Question 31
Correct
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Which of the following is NOT an advantage of a case-control study used to identify past exposure to a risk factor in patients with a disease:
Your Answer: Can directly measure absolute and relative risk of a disease
Explanation:Advantages:relatively quickrelatively cheap and easy to performparticularly suitable for studying associations between an exposure and an outcome when the outcome is uncommon or if the outcome occurs decades after exposurea wide range of risk factors can be investigated in each studyDisadvantages:subject to recall biasunlike in a whole population study, absolute risk cannot be quantifiedtemporal relationship between exposure and outcome can be difficult to establishunsuitable for rare risk factorsprone to confounding
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This question is part of the following fields:
- Evidence Based Medicine
- Study Methodology
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Question 32
Correct
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Regarding the foetal oxygen-haemoglobin dissociation curve, which of the following statements is CORRECT:
Your Answer: The HbF dissociation curve lies to the left of that for HbA.
Explanation:Foetal haemoglobin (HbF) has a higher affinity for oxygen than adult haemoglobin (HbA) because it’s gamma chains bind 2,3-DPG less avidly than beta chains of HbA. The HbF dissociation curve lies to the left of that for HbA. In the placenta PCO2moves from the foetal to the maternal circulation, shifting the maternal curve further right and the foetal curve further left (the double Bohr effect). The higher affinity of HbF relative to HbA helps transfer oxygen from mother to foetus. Therefore even through blood returning from the placenta to the foetus in the umbilical vein has a PO2of only about 4 kPa, its saturation is 70%. Oxygen transport in the foetus is also helped by a high Hb of about 170 – 180 g/L.
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This question is part of the following fields:
- Physiology
- Respiratory
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Question 33
Incorrect
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Which of the following muscles acts as an extensor of the shoulder joint?
Your Answer: Pectoralis major
Correct Answer: Teres major
Explanation:The glenohumeral joint possesses the capability of allowing an extreme range of motion in multiple planes.Flexion – Defined as bringing the upper limb anterior in the sagittal plane. The usual range of motion is 180 degrees. The main flexors of the shoulder are the anterior deltoid, coracobrachialis, and pectoralis major. Biceps brachii also weakly assists in this action.Extension—Defined as bringing the upper limb posterior in a sagittal plane. The normal range of motion is 45 to 60 degrees. The main extensors of the shoulder are the posterior deltoid, latissimus dorsi, and teres major.Internal rotation—Defined as rotation toward the midline along a vertical axis. The normal range of motion is 70 to 90 degrees. The internal rotation muscles are the subscapularis, pectoralis major, latissimus dorsi, teres major, and the anterior aspect of the deltoid.External rotation – Defined as rotation away from the midline along a vertical axis. The normal range of motion is 90 degrees. Primarily infraspinatus and teres minor are responsible for the motion.Adduction – Defined as bringing the upper limb towards the midline in the coronal plane. Pectoralis major, latissimus dorsi, and teres major are the muscles primarily responsible for shoulder adduction.Abduction – Defined as bringing the upper limb away from the midline in the coronal plane. The normal range of motion is 150 degrees. Due to the ability to differentiate several pathologies by the range of motion of the glenohumeral joint in this plane of motion, it is essential to understand how different muscles contribute to this action.
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This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 34
Incorrect
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Which of the following is NOT a feature characteristic of intravascular haemolysis:
Your Answer: Haemosiderinuria
Correct Answer: Bilirubinuria
Explanation:Features of intravascular haemolysis include:haemoglobinaemia, methaemalbuminaemia, haemoglobinuria (dark urine) and haemosiderinuria
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This question is part of the following fields:
- Haematology
- Pathology
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Question 35
Correct
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A 70-year-old patient diagnosed with Cushing's syndrome and has a history of weight gain, hypertension, and easy bruising.Which of these assertions about Cushing's syndrome is correct?
Your Answer: Diagnosis can be confirmed by a dexamethasone suppression test
Explanation:Cushing’s syndrome is a group of symptoms and signs brought on by long-term exposure to high amounts of endogenous or exogenous glucocorticoids.Iatrogenic corticosteroid injection is the most prevalent cause of Cushing’s syndrome. Cushing’s illness is the second most prevalent cause of Cushing’s syndrome. Cushing’s disease is distinct from Cushing’s syndrome in that it refers to a single cause of the illness, a pituitary adenoma that secretes high quantities of ACTH, which raises cortisol levels.Because cortisol enhances the vasoconstrictive impact of endogenous adrenaline, patients with Cushing’s syndrome are usually hypertensive.Hyperglycaemia (due to insulin resistance) rather than hypoglycaemia is a common symptom.Cortisol levels fluctuate throughout the day, with the greatest levels occurring around 0900 hours and the lowest occurring at 2400 hrs during sleep. The diurnal swing of cortisol levels is lost in Cushing’s syndrome, and levels are greater throughout the 24-hour period. In the morning, levels may be normal, but they may be high at night-time, when they are generally repressed.A dexamethasone suppression test or a 24-hour urine free cortisol collection can both be used to establish the existence of Cushing’s syndrome.
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This question is part of the following fields:
- Endocrine Physiology
- Physiology
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Question 36
Correct
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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?Â
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.
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This question is part of the following fields:
- Infections
- Pharmacology
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Question 37
Correct
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A dermatological examination on a patient presenting with a lump shows a small visible skin elevation containing an accumulation of pus.Which one of these best describes the lump you have found on examination?
Your Answer: Pustule
Explanation:A pustule is a small visible skin elevation containing an accumulation of pus. A carbuncle is a collection of individual boils clustered together. A bulla is a visible collection of clear fluid measuring greater than 0.5 cm in diameter. A furuncle, or boil, is a pyogenic infection of the hair follicle commonly caused by infection with Staphylococcus aureus. A vesicle is a visible collection of fluid measuring less than 0.5 cm in diameter.
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This question is part of the following fields:
- General Pathology
- Pathology
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Question 38
Incorrect
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A patient with profuse watery diarrhoea was found to have C. difficile cytotoxin. Which of the following complications is NOT a typical complication of pseudomembranous colitis:
Your Answer: Acute kidney injury
Correct Answer: Volvulus
Explanation:Dehydration, electrolyte imbalance, acute kidney injury secondary to diarrhoea, toxic megacolon, bowel perforation, and sepsis secondary to intestinal infection are all possible complications of pseudomembranous colitis. When the intestine twists around itself and the mesentery that supports it, an obstruction is created. This condition is known as a volvulus. Volvulus is caused by malrotation and other anatomical factors, as well as postoperative abdominal adhesions, and not by Clostridium difficile infection.
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This question is part of the following fields:
- Microbiology
- Pathogens
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Question 39
Correct
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A patient suffers a lower limb fracture that causes damage to the nerve that innervates peroneus brevis.Peroneus brevis receives its innervation from which of the following nerves? Select ONE answer only.
Your Answer: Superficial peroneal nerve
Explanation:Peroneus brevis is innervated by the superficial peroneal nerve.Peroneus longus is innervated by the superficial peroneal nerve.Peroneus tertius is innervated by the deep peroneal nerve.
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This question is part of the following fields:
- Anatomy
- Lower Limb
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Question 40
Correct
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Intravenous glucose solutions are typically used in the treatment of all of the following situations except:
Your Answer: Hypokalaemia
Explanation:In hypokalaemia, initial potassium replacement therapy should not involve glucose infusions, as glucose may cause a further decrease in the plasma-potassium concentration. Glucose infusions are used for the other indications like diabetic ketoacidosis, hypoglycaemia, routine fluid maintenance in patients who are nil by mouth (very important in children), and in hyperkalaemia.
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This question is part of the following fields:
- Fluids And Electrolytes
- Pharmacology
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Question 41
Correct
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Question 42
Correct
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Which of the following tracts must be affected if a patient presents with decreased pain and temperature sensation in both lower extremities?
Your Answer: The lateral spinothalamic tract
Explanation:The main function of the spinothalamic tract is to carry pain and temperature via the lateral part of the pathway and crude touch via the anterior part. The spinothalamic tract pathway is an imperative sensory pathway in human survival because it enables one to move away from noxious stimuli by carrying pain and temperature information from the skin to the thalamus where it is processed and transmitted to the primary sensory cortex. The primary sensory cortex communicates with the primary motor cortex, which lies close to it, to generate rapid movement in response to potentially harmful stimuli. Furthermore, the spinothalamic tract has a role in responding to pruritogens, causing us to itch. Interestingly, itching suppresses the spinothalamic tract neuron response to the histamine effect.
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This question is part of the following fields:
- Anatomy
- Central Nervous System
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Question 43
Correct
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Which of the following is a physiological function that is mediated by a hormone released by the posterior pituitary:
Your Answer: Water retention
Explanation:Antidiuretic hormone (ADH), released by the posterior pituitary, acts on the kidneys to increase water permeability in the distal nephron allowing greater water reabsorption and concentration of urine. Prolactin, from the anterior pituitary, is responsible for milk production. The thyroid hormones, from the thyroid gland, are responsible for an increase in basal metabolic rate (stimulated by TSH from the anterior pituitary). FSH/LH, from the anterior pituitary, are responsible for maturation of egg and sperm. Calcitonin, from the thyroid gland, is responsible for decreasing calcium levels.
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This question is part of the following fields:
- Endocrine
- Physiology
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Question 44
Correct
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The role of the juxtaglomerular (granular) cells of the juxtaglomerular apparatus is:
Your Answer: Production of renin
Explanation:Juxtaglomerular cells synthesise renin. These cells are specialised smooth muscle cells that are located in the walls of the afferent arterioles, and there are some in the efferent arterioles.
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This question is part of the following fields:
- Physiology
- Renal
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Question 45
Correct
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A 42-year-old woman presents with face swelling prominently affecting her upper lip and hands. She has previously been diagnosed with hereditary angioedema.Which of these is the most appropriate management option for this acute attack?
Your Answer: Fresh frozen plasma
Explanation:Hereditary angioedema is inherited as an autosomal dominant disorder and is caused by deficiency of C1 esterase inhibitor, a protein that forms part of the complement system.Attacks can be precipitated by stress and minor surgical procedures. Clinical features of hereditary angioedema include oedema of the skin and mucous membranes commonly affecting the face, tongue and extremities.Angioedema and anaphylaxis due to a deficiency of C1 esterase inhibitor are resistant to adrenaline, steroids and antihistamines. Treatment is with fresh frozen plasma or C1 esterase inhibitor concentrate, which contains C1 esterase inhibitor.Short-term prophylaxis for events that may precipitate angioedema attack is achieved with C1 esterase inhibitor or fresh frozen plasma infusions before the event while long-term prophylaxis can be achieved with antifibrinolytic drugs (tranexamic acid) or androgenic steroids.
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This question is part of the following fields:
- Pharmacology
- Respiratory Pharmacology
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Question 46
Incorrect
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A 24-year-old patient is suspected to have a possible acute hepatitis B infection and is currently under investigation.Which of the following markers is considered the earliest indicator of acute infection in acute Hepatitis B?
Your Answer: IgM antibody to hepatitis B core antigen
Correct Answer: Hepatitis B surface Ag
Explanation:HBsAg is the serological hallmark of HBV infection. After an acute exposure to HBV, HBsAg appears in serum within 1 to 10 weeks. Persistence of this marker for more than 6 months implies chronic HBV infection.Anti-HBs is known as a neutralizing antibody, and confers long-term immunity. In patients with acquired immunity through vaccination, anti-HBs is the only serological marker detected in serum.HBcAg is an intracellular presence in infected hepatocyte, thus it is not identified in the serum. During acute infection, anti-HBc IgM and IgG emerges 1–2 weeks after the presence of HBsAg along with raised serum aminotransferase and symptoms. After 6 months of acute infection, anti-HBc IgM wears off. Anti-HBc IgG continues to detect in both patients with resolved HBV infection and chronic hepatitis B.Hepatitis D virus, also known as the delta hepatitis virus, is a defective ssRNA virus that requires HBV for replication. The infection can occur in one of two clinical forms, co-infection or superinfection. In a co-infection, the patient is simultaneously infected with HBV and HDV. In a superinfection, an HDV infection develops in a patient with a chronic HBV infection.
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This question is part of the following fields:
- Microbiology
- Specific Pathogen Groups
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Question 47
Correct
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Regarding cytotoxic T cells, which of the following statements is CORRECT:
Your Answer: They kill target cells by inducing cell apoptosis.
Explanation:CD8+ T-cells (Cytotoxic T cells)Recognise antigen only in association with HLA Class I molecules (found on all nucleated cells; present endogenous antigens such as those found in cells infected by viruses or intracellular bacteria.)Comprise about 25% of peripheral T-cellsResponsible for cytotoxic killing of target cells
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This question is part of the following fields:
- Immune Responses
- Pathology
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Question 48
Correct
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Question 49
Correct
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A 64-year-old man presents with an acute episode of gout. He has a history of chronic heart failure and hypertension. His current medications include ramipril and furosemide.Which of the following statements regarding the treatment of gout is true? Select ONE answer only.
Your Answer: Colchicine has a role in prophylactic treatment
Explanation:In the absence of any contra-indications, high-dose NSAIDs are the first-line treatment for acute gout. Naproxen 750 mg as a stat dose followed by 250 mg TDS is a commonly used and effective regime.Aspirin should not be used in gout as it reduces the urinary clearance of urate and interferes with the action of uricosuric agents. Naproxen, Diclofenac or Indomethacin are more appropriate choices.Allopurinol is used prophylactically, preventing future attacks by reducing serum uric acid levels. It should not be started in the acute phase as it increases the severity and duration of symptoms.Colchicine acts on the neutrophils, binding to tubulin to prevent neutrophil migration into the joint. It is as effective as NSAIDs in relieving acute attacks. It also has a role in prophylactic treatment if Allopurinol is not tolerated.NSAIDs are contra-indicated in heart failure as they can cause fluid retention and congestive cardiac failure. Colchicine is the preferred treatment in patients with heart failure or those who are intolerant of NSAIDs.
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This question is part of the following fields:
- Musculoskeletal Pharmacology
- Pharmacology
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Question 50
Incorrect
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A 45-year-old man had a painless superficial inguinal lymphadenopathy. It was later found to be malignant. Which of the following parts of the body is most likely the origin of this cancerous lymph node?
Your Answer: Prostate
Correct Answer: Anal canal
Explanation:A cancer of the anal canal below the pectinate line would spread to the superficial inguinal lymph nodes. Anal cancer often spreads through lymphatic drainage to the internal iliac lymph nodes in lesions above the pectinate line and to the superficial inguinal lymph nodes in lesions below the pectinate line.
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This question is part of the following fields:
- Abdomen
- Anatomy
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Question 51
Incorrect
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Regarding Clostridium perfringens, which of the following statements is CORRECT:
Your Answer: It has endotoxin-mediated effects in tissue causing severe tissue damage.
Correct Answer: It can cause exotoxin-mediated food poisoning.
Explanation:Clostridium perfringens is an obligate anaerobe and has exotoxin mediated effects. It is the most common cause of gas gangrene. C. perfringens is also implicated in food poisoning, cellulitis, enteritis necrotican (life-threatening infection involving ischaemic necrosis of the jejunum), and rarely, CNS infections such as meningitis and encephalitis.
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This question is part of the following fields:
- Microbiology
- Pathogens
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Question 52
Correct
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Question 53
Correct
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Which of the following describes the pulse pressure:
Your Answer: Systolic - diastolic pressure
Explanation:During systole, the pressure in the left ventricle increases and blood is ejected into the aorta. The rise in pressure stretches the elastic walls of the aorta and large arteries and drives blood flow. Systolic pressure is the maximum arterial pressure during systole. During diastole, arterial blood flow is partly maintained by elastic recoil of the walls of large arteries. The minimum pressure reached before the next systole is the diastolic pressure. The difference between the systolic and diastolic pressure is the pulse pressure.
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This question is part of the following fields:
- Cardiovascular
- Physiology
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Question 54
Incorrect
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On his stool culture, a patient with a diarrhoeal illness grows Escherichia coli.What SINGLE statement about Escherichia coli is true?
Your Answer: It is a coccus
Correct Answer: Most serotypes are harmless
Explanation:Escherichia coli is a Gram-negative, non-spore forming, facultative anaerobic, rod-shaped bacterium. Although some can cause serious food poisoning, most serotypes are harmless.Escherichia coli is transmitted via the faeco-oral route.
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This question is part of the following fields:
- Microbiology
- Specific Pathogen Groups
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Question 55
Correct
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Which of the following statements concerning hepatitis D is TRUE:
Your Answer: It can only be transmitted with, or to somebody who is infected with, Hepatitis B.
Explanation:Hepatitis D virus (HDV) is an RNA virus that was discovered in 1977 and is structurally unrelated to the hepatitis A (HAV), hepatitis B (HBV), and hepatitis C (HCV) viruses. HDV causes a unique infection that requires the assistance of HBV viral particles to replicate and infect hepatocytes. Its clinical course is varied and ranges from acute, self-limited infection to acute, fulminant liver failure. Chronic liver infection can lead to end-stage liver disease and associated complications (including accelerated fibrosis, liver decompensation, and hepatocellular carcinoma).
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This question is part of the following fields:
- Microbiology
- Pathogens
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Question 56
Incorrect
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Which of the following is typically a cause of a normal anion gap metabolic acidosis:
Your Answer: Propylene glycol overdose
Correct Answer: Diarrhoea
Explanation:FUSEDCARS can be used to remember some of the causes of a normal anion gap acidosis:Fistula (pancreaticoduodenal)Ureteroenteric conduitSaline administrationEndocrine (hyperparathyroidism)DiarrhoeaCarbonic anhydrase inhibitors (e.g. acetazolamide)Ammonium chlorideRenal tubular acidosisSpironolactone
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This question is part of the following fields:
- Physiology
- Renal
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Question 57
Correct
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Question 58
Incorrect
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Which of the following accurately describes the extensor pollicis brevis muscle?
Your Answer: It extends the distal phalanx of the thumb at the metacarpophalangeal joint
Correct Answer: It lies on the medial side of abductor pollicis longus
Explanation:Extensor pollicis brevis is a short and slender muscle located in the posterior compartment of the forearm, extending from the posterior surface of radius to the proximal phalanx of thumb. It is one of the deep extensors of the forearm, together with supinator, abductor pollicis longus, extensor pollicis longus and extensor indicis muscles.Extensor pollicis brevis is a deep extensor of the thumb that lies deep to extensor digitorum muscle. It sits directly medial to abductor pollicis longus and posterolateral to extensor pollicis longus muscle. Just above the wrist, extensor pollicis brevis obliquely crosses the tendons of extensor carpi radialis brevis and extensor carpi radialis longus muscles.Extensor pollicis brevis is innervated by posterior interosseous nerve which is a continuation of a deep branch of radial nerve (root value C7 and C8).Extensor pollicis brevis receives its blood supply by posterior interosseous artery and perforating branches from the anterior interosseous artery, which are the branches of common interosseous artery. The common interosseous artery arises immediately below the tuberosity of radius from the ulnar artery.Together with extensor pollicis longus, extensor pollicis brevis is in charge of extension of the thumb in the first metacarpophalangeal joint. It also extends the thumb in the carpometacarpal joint of the thumb. This movement is important in the anatomy of the grip, as it enables letting go of an object. As it crosses the wrist, extensor pollicis brevis also participates in the extension and abduction of this joint.
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This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 59
Incorrect
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A 30-year-old female presented to the Emergency Department after a fall during a hiking expedition caused severe pain in her left arm and wrist drop. An X-ray revealed a mid-shaft fracture of the humerus, which most likely damaged the radial nerve. Which one of the following statements best describes the healing process of peripheral nerves?
Your Answer:
Correct Answer: Peripheral nerve fibres regenerate at around 1mm per day
Explanation:Peripheral nerves are nerves that lie outside the brain and spinal cord. Peripheral nerves readily regenerate, while central nervous system axonal injury does not spontaneously regenerate. If there is damage to the axons of peripheral nerves, the nerves will regenerate at a slow rate of 1 mm per day. The slow regeneration process may lead to muscle atrophy before regeneration is complete. Each peripheral nerve has a single cell body that supplies nutrients to the growing nerve fibre. The cell body does not undergo mitosis; only the axon is regenerated.Schwann cells of the peripheral nervous system provide support for this process, while the analogous oligodendrocytes of the central nervous system do not. Schwann cells themselves do not cause regeneration. Schwann cells provide myelin for myelinated fibres and surround non-myelinated fibres with their cytoplasm. If an axon is completely severed, as in the case of amputation, the axonal fibres regenerating from the cell body may never find their original route back to the muscle. Instead, they may form a traumatic neuroma, a painful collection of nerve fibres and myelin.
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This question is part of the following fields:
- General Pathology
- Pathology
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Question 60
Incorrect
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Which of the following statements about lithium treatment is FALSE:
Your Answer:
Correct Answer: Concomitant treatment with NSAIDs decreases serum-lithium concentration.
Explanation:Lithium levels are raised by NSAIDs because renal clearance is reduced. Lithium is a small ion (74 Daltons) with no protein or tissue binding and is therefore amenable to haemodialysis. Lithium is freely distributed throughout total body water with a volume of distribution between 0.6 to 0.9 L/kg, although the volume may be smaller in the elderly, who have less lean body mass and less total body water. Steady-state serum levels are typically reached within five days at the usual oral dose of 1200 to 1800 mg/day. The half-life for lithium is approximately 18 hours in adults and 36 hours in the elderly.Lithium is excreted almost entirely by the kidneys and is handled in a manner similar to sodium. Lithium is freely filtered but over 60 percent is then reabsorbed by the proximal tubules.
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This question is part of the following fields:
- Central Nervous System
- Pharmacology
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Question 61
Incorrect
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Which of the following is an example of continuous data:
Your Answer:
Correct Answer: Height
Explanation:Continuous data is data where there is no limitation on the numerical value that the variable can take e.g. weight, height.
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This question is part of the following fields:
- Evidence Based Medicine
- Statistics
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Question 62
Incorrect
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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:
Correct 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.
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This question is part of the following fields:
- Cardiovascular Pharmacology
- Pharmacology
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Question 63
Incorrect
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Atrial natriuretic peptide (ANP) is primarily produced in response to:
Your Answer:
Correct Answer: An increase in intravascular fluid volume
Explanation:Atrial natriuretic peptide (ANP) is released from cardiac atrial muscle cells in response to atrial stretch caused by an increase in intravascular fluid volume and is also produced in collecting duct cells.Atrial natriuretic peptide acts to inhibit sodium reabsorption in the distal nephron.
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This question is part of the following fields:
- Physiology
- Renal
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Question 64
Incorrect
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A 54-year-old man with a long history of poorly controlled hypertension complains of a headache and vision blurring today. In triage, his blood pressure is 210/192 mmHg. A CT head scan is scheduled to rule out the possibility of an intracranial haemorrhage. You make the diagnosis of hypertensive encephalopathy and rush the patient to reus to begin blood pressure-lowering treatment. He has a history of brittle asthma, for which he has been admitted to the hospital twice in the last year.Which of the following is the patient's preferred drug treatment?
Your Answer:
Correct Answer: 25% of the mean arterial pressure over the first hour
Explanation:End-organ damage (e.g. encephalopathy, intracranial haemorrhage, acute myocardial infarction or ischaemia, dissection, pulmonary oedema, nephropathy, eclampsia, papilledema, and/or angiopathic haemolytic anaemia) characterises a hypertensive emergency (also known as ‘accelerated hypertension’ or malignant hypertension’ It’s a life-threatening condition that necessitates rapid blood pressure reduction to avoid end-organ damage and a negative outcome.Hypertensive encephalopathy is a syndrome that includes headaches, seizures, visual changes, and other neurologic symptoms in people who have high blood pressure. It is reversible if treated quickly, but it can progress to coma and death if not treated properly.Any patient with suspected hypertensive encephalopathy should have an urgent CT scan to rule out an intracranial haemorrhage, as rapid blood pressure reduction could be dangerous in these circumstances.The drug of choice is labetalol, which reduces blood pressure steadily and consistently without compromising cerebral blood flow.An initial reduction of approximately 25% in mean arterial pressure (MAP) over an hour should be aimed for, followed by a further controlled MAP reduction over the next 24 hours. In patients who are unable to take beta-blockers, nicardipine can be used as a substitute.
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This question is part of the following fields:
- Cardiovascular Pharmacology
- Pharmacology
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Question 65
Incorrect
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A suspicious growth on the posterior tongue of a 40-year-old man was discovered by his dentist and was immediately referred for possible oral cancer. The lymph from the posterior tongue will drain to which of the following nodes?
Your Answer:
Correct Answer: Deep cervical nodes
Explanation:Lymph from the medial anterior two thirds of the tongue travels to the deep cervical lymph nodes.Lymph from the lateral anterior tongue goes to the submandibular nodes.
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This question is part of the following fields:
- Anatomy
- Head And Neck
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Question 66
Incorrect
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Which of the following is an adverse effect of carbamazepine:
Your Answer:
Correct Answer: Aplastic anaemia
Explanation:Common adverse effects include nausea and vomiting, sedation, dizziness, headache, blurred vision and ataxia. These adverse effects are dose related and are most common at the start of treatment.Other adverse effects include:Allergic skin reactions (and rarely, more serious dermatological conditions)Hyponatraemia (avoid concomitant use with diuretics)Leucopenia, thrombocytopenia and other blood disorders including aplastic anaemiaHepatic impairment
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This question is part of the following fields:
- Central Nervous System
- Pharmacology
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Question 67
Incorrect
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What is the main mechanism of action of dobutamine as an inotropic sympathomimetic:
Your Answer:
Correct Answer: Beta1-receptor agonist
Explanation:Dobutamine directly stimulates the beta1-adrenergic receptors in the heart and increases contractility and cardiac output with little effect on the rate. In addition action on beta2-receptors causes vasodilation.
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This question is part of the following fields:
- Cardiovascular
- Pharmacology
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Question 68
Incorrect
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A 60-year-old female has a past medical history of diverticular disease. She now presents in the clinic with crampy abdominal pain. The nurse at the triage suggests prescribing hyoscine butyl bromide to help relieve the abdominal pain. However, after administering this treatment, the patient develops a side-effect to the medication. What side-effect of using hyoscine butyl bromide is she MOST likely to develop out of the following?
Your Answer:
Correct Answer: Dry mouth
Explanation:Hyoscine butylbromide is an antispasmodic drug that blocks muscarinic receptors and reduces intestinal motility. It is used for gastrointestinal and genitourinary smooth muscle spasms and symptomatic relief of IBS.It has the following side-effects:1. Constipation2. Dizziness3. Drowsiness4. Dry mouth5. Dyspepsia6. Flushing7. Headache8. Nausea and vomiting9. Palpitations10. Skin reactions11. Tachycardia12. Urinary disorders13. Disorders of vision
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This question is part of the following fields:
- Gastrointestinal Pharmacology
- Pharmacology
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Question 69
Incorrect
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Which of the following does NOT affect the rate of flow of a liquid through a tube:
Your Answer:
Correct Answer: Surface tension
Explanation:Flow through a tube is dependent upon:The pressure difference across the ends of the tube (P1– P2)The resistance to flow provided by the tube (R)This is Darcy’s law, which is analogous to Ohm’s law in electronics:Flow = (P1– P2) / RResistance in the tube is defined by Poiseuille’s law, which is determined by the diameter of the tube and the viscosity of the fluid. Poiseuille’s law is as follows:Resistance = (8VL) / (πR4)Where:V = The viscosity of the fluidL = The length of the tubeR = The radius of the tubeTherefore, in simple terms, resistance is directly proportional to the viscosity of the fluid and the length of the tube and inversely proportional to the radius of the tube. Of these three factors, the most important quantitatively and physiologically is vessel radius.It can be seen that small changes in the radius can have a dramatic effect on the flow of the fluid. For example, the constriction of an artery by 20% will decrease the flow by approximately 60%.Another important and frequently quoted example of this inverse relationship is that of the radius of an intravenous cannula. Doubling the diameter of a cannula increases the flow rate by 16-fold (r4). This is the reason the diameter of an intravenous cannula in resuscitation scenarios is so important.*Please note that knowledge of the detail of Poiseuille’s law is not a requirement of the RCEM Basic Sciences Curriculum.
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This question is part of the following fields:
- Basic Cellular
- Physiology
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Question 70
Incorrect
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A 28-year-old known intravenous drug user has a history of persistent high-fever. On examination you hear a harsh systolic murmur and the patient says a murmur has never been heard before in previous hospital visits. A diagnosis of endocarditis is suspect.Which of these antibacterial agents would be most appropriate to prescribe in this case?
Your Answer:
Correct Answer: Flucloxacillin and gentamicin
Explanation:Endocarditis is infective or non infective inflammation (marantic endocarditis) of the inner layer of the heart and it often involves the heart valves.Risk factors include:Prosthetic heart valvesCongenital heart defectsPrior history of endocarditisRheumatic feverIllicit intravenous drug useIn the presentation of endocarditis, the following triad is often quoted:Persistent feverEmbolic phenomenaNew or changing murmurFlucloxacillin and gentamicin are current recommended by NICE and the BNF for the initial ‘blind’ therapy in endocarditis.
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This question is part of the following fields:
- Microbiology
- Specific Pathogen Groups
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Question 71
Incorrect
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A 23-year-old male is referred to your haematology clinic after an acute attack of haemolytic anaemia. He was diagnosed with glucose-6-phosphate dehydrogenase deficiency ten years ago. Which ONE of the following options is FALSE with regards to this disorder?
Your Answer:
Correct Answer: Acute haemolysis can be triggered by cephalosporin antibiotics
Explanation:Glucose-6-phosphate dehydrogenase deficiency is an X-linked recessive disorder in which there is a deficiency of the enzyme G6PD. This causes instability of red blood cell membranes under oxidative stress leading to haemolysis.Triggers include: 1) Fava beans2) Sulphonamides3) Primaquine4) Anti-TB drugs5) Infections Most individuals will be asymptomatic until exposed to one of the triggers listed above. It is the commonest human enzyme defect and affects males more than females because of the X-linked inheritance pattern. The use of penicillins and cephalosporins is generally safe.
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This question is part of the following fields:
- Haematology
- Pathology
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Question 72
Incorrect
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A 15-year-old boy was brought to the emergency room with complaints of a headache, stiffness of the neck, and photophobia. Upon observation, the following were noted: HR 124, BP 86/43, RR 30, SaO 95%, temperature 39.5 deg C. A recently developed non-blanching rash on his legs was also observed.What is most likely the causative agent of the case presented above?
Your Answer:
Correct Answer: Neisseria meningitidis group B
Explanation:The meningococcus is solely a human pathogen, and up to 50% of the population may carry meningococci in the nasopharynx. Factors that lead to invasion and production of disease include complex inter-relationships of genetic predisposition, host status, environmental conditions, and virulence of the organism.Meningococcal disease is the most common infectious cause of death in childhood in developed countries. It presents as septicaemia, meningitis, or a combination. Septicaemia is the more dangerous presentation, especially with septic shock; meningitis is more likely to lead to neurodevelopmental sequelae. Classic features of septicaemia are a non-blanching rash in a feverish, ill child.
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This question is part of the following fields:
- Microbiology
- Specific Pathogen Groups
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Question 73
Incorrect
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A 50-year-old woman with painful joints had some blood tests done with her GP. The test showed she had anti-double stranded DNA antibodies.Which one of these disorders is most likely to be associated with anti-double stranded DNA antibodies?
Your Answer:
Correct Answer: Systemic lupus erythematosus (SLE)
Explanation:CREST syndrome is usually associated with anti-centromere antibodies.Primary biliary cirrhosis is associated with anti-mitochondrial antibodies.Sjogren’s syndrome is associated with anti-Ro and anti-La antibodies.Polymyositis is associated with anti-Jo1 antibodies.Anti-double stranded DNA antibodies are highly characteristic of systemic lupus erythematosus (SLE). They are a group of anti-nuclear antibodies (ANA) that target double stranded DNA and are implicated in the pathogenesis of lupus nephritis.
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This question is part of the following fields:
- General Pathology
- Pathology
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Question 74
Incorrect
-
Which of the following is NOT a typical feature of lithium toxicity:
Your Answer:
Correct Answer: Miosis
Explanation:Features of toxicity include:Increasing gastrointestinal disturbances (vomiting, diarrhoea, anorexia)Visual disturbancesPolyuria and incontinenceMuscle weakness and tremorTinnitusCNS disturbances (dizziness, confusion and drowsiness increasing to lack of coordination, restlessness, stupor)Abnormal reflexes and myoclonusHypernatraemiaWith severe overdosage (serum-lithium concentration > 2 mmol/L) seizures, cardiac arrhythmias (including sinoatrial block, bradycardia and first-degree heart block), blood pressure changes, electrolyte imbalance, circulatory failure, renal failure, coma and sudden death may occur.
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This question is part of the following fields:
- Central Nervous System
- Pharmacology
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Question 75
Incorrect
-
A patient presents with a necrolytic migratory rash. Her blood serum glucagon concentration is 1246 pg/mL. Following further investigations, she is diagnosed with glucagonoma.Which SINGLE statement regarding glucagon is true?
Your Answer:
Correct Answer: It makes fatty acids available for oxidation
Explanation:Glucagon is a peptide hormone that is produced and secreted by alpha cells of the islets of Langerhans, which are located in the endocrine portion of the pancreas. The main physiological role of glucagon is to stimulate hepatic glucose output, thereby leading to increases in glycaemia. It provides the major counter-regulatory mechanism to insulin in maintaining glucose homeostasis.Hypoglycaemia is the principal stimulus for the secretion of glucagon but may also be used as an antidote in beta-blocker overdose and in anaphylaxis in patients on beta-blockers that fail to respond to adrenaline. Glucagon then causes:GlycogenolysisGluconeogenesisLipolysis in adipose tissueThe secretion of glucagon is also stimulated by:AdrenalineCholecystokininArginineAlanineAcetylcholineThe secretion of glucagon is inhibited by:InsulinSomatostatinIncreased free fatty acidsIncreased urea productionGlycolysis is the metabolic pathway that converts glucose into pyruvate. The free energy released by this process is used to form ATP and NADH. Glycolysis is inhibited by glucagon, and glycolysis and gluconeogenesis are reciprocally regulated so that when one cell pathway is activated, the other is inactive and vice versa.Glucagon has a minor effect of enhancing lipolysis in adipose tissue. Lipolysis is the breakdown of lipids and involves the hydrolysis of triglycerides into glycerol and free fatty acids. It makes fatty acids available for oxidation.
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This question is part of the following fields:
- Endocrine Physiology
- Physiology
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Question 76
Incorrect
-
Regarding haemophilia A, which of the following statements is INCORRECT:
Your Answer:
Correct Answer: In haemophilia both the APTT and PT are prolonged.
Explanation:Haemophilia A is the most common of the hereditary clotting factor deficiencies. The inheritance is sex-linked but up to one-third of patients have no family history and these cases result from recent mutation. The vast majority of cases are inherited in an X-linked recessive fashion, affecting males born to carrier mothers. Females born to affected fathers can also, rarely, be affected due to homozygosity for the gene, where there is marriage to close relatives. The defect is an absence or low level of plasma factor VIII. The APTT is prolonged but the PT is normal. Recurrent painful haemarthroses and muscle haematomas dominate the clinical course of severely affected patients and if inadequately treated, lead to progressive joint deformity and disability. Local pressure can cause entrapment neuropathy or ischaemic necrosis. Prolonged bleeding occurs after dental extractions or post-trauma. Spontaneous haematuria and gastrointestinal haemorrhage may occur. The clinical severity of the disease correlates inversely with the factor VIII level. Operative and post-traumatic haemorrhage are life-threatening both in severely and mildly affected patients.
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This question is part of the following fields:
- Haematology
- Pathology
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Question 77
Incorrect
-
A 62 year old man has sustained a penetrating injury to the submandibular triangle. On examination, his tongue is weak and when protruded deviates to the left. Which of the following nerves has most likely been injured:
Your Answer:
Correct Answer: Left hypoglossal nerve
Explanation:Damage to the hypoglossal nerve results in weakness of the tongue, with deviation of the tongue towards the weak side on protrusion.
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This question is part of the following fields:
- Anatomy
- Cranial Nerve Lesions
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Question 78
Incorrect
-
Normal human immunoglobulin is mostly used to protect against which of the following infectious diseases?
Your Answer:
Correct Answer: Measles and hepatitis A
Explanation:Immune globulin IM is indicated for prophylaxis following exposureto hepatitis A, to prevent or modify measles (rubeola) in a susceptible person exposed fewer than 6 days previously,for susceptible household contacts of measles patients,particularly contacts <1 year and pregnant women without evidence of immunity, and to modify rubella in exposed pregnant women who will not consider a therapeutic abortion.
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This question is part of the following fields:
- Immunoglobulins And Vaccines
- Pharmacology
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Question 79
Incorrect
-
A patient presents with an acute severe asthma attack. Following a poor response to his initial salbutamol nebuliser, you administer a further nebuliser that this time also contains ipratropium bromide.After what time period would you expect the maximum effect of the ipratropium bromide to occur? Select ONE answer only.
Your Answer:
Correct Answer: 30 -60 minutes
Explanation:Ipratropium bromide is an antimuscarinic drug used in the management of acute asthma and COPD. It can provide short-term relief in chronic asthma, but short-acting β2agonists act more quickly and are preferred.The BTS guidelines recommend that nebulised ipratropium bromide (0.5 mg 4-6 hourly) can be added to β2agonist treatment for patients with acute severe or life-threatening asthma or those with a poor initial response to β2 agonist therapy.The aerosol inhalation of ipratropium can be used for short-term relief in mild chronic obstructive pulmonary disease in patients who are not already using a long-acting antimuscarinic drug (e.g. tiotropium).Its maximum effect occurs 30-60 minutes after use; its duration of action is 3-6 hours, and bronchodilation can usually be maintained with treatment three times per day.The commonest side effect of ipratropium bromide is dry mouth. It can also trigger acute closed-angle glaucoma in susceptible patients. Tremor is commonly seen with β2agonists but not with antimuscarinics. Ipratropium bromide should be used with caution in: Men with prostatic hyperplasia and bladder-outflow obstruction (worsened urinary retention has been reported in elderly men), People with chronic kidney disease (CKD) stages 3 and above (because of the risk of drug toxicity), People with angle-closure glaucoma (nebulised mist of antimuscarinic drugs can precipitate or worsen acute angle-closure glaucoma)
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This question is part of the following fields:
- Pharmacology
- Respiratory Pharmacology
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Question 80
Incorrect
-
A 35-year-old man is feeling unwell following his return from a business trip. He is diagnosed with a vector transmitted disease.Which of these organisms is commonly spread by vector-borne transmission?
Your Answer:
Correct Answer: Borrelia burgdorferi
Explanation:Borrelia burgdorferiis, primarily spread by ticks and lice, is a zoonotic, vector-borne organism that causes Lyme disease.Neisseria meningitidis and Bordetella pertussis are droplet borne infections (airborne particle > 5 µm)Vibrio cholerae and Ascaris lumbricoides are spread by the faeco-oral route
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This question is part of the following fields:
- Microbiology
- Principles Of Microbiology
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Question 81
Incorrect
-
Regarding dermatophytes, which of the following statement is CORRECT:
Your Answer:
Correct Answer: Diagnosis is made from microscopy and culture of skin scrapings, hair samples or nail clippings.
Explanation:Diagnosis is made from microscopy and culture of skin scrapings, hair samples or nail clippings depending on the site of infection. The lesions of ringworm typically have a dark outer ring with a pale centre. Tinea capitis is ringworm affecting the head and scalp. Spread is via direct skin contact. Treatment is usually topical, oral antifungals are reserved for refractory infection.
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This question is part of the following fields:
- Microbiology
- Pathogens
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Question 82
Incorrect
-
A 7-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 non-blanching rash on legs and arms. The GP administered a dose of antibiotics before transferring child to the Emergency Department.Which of these is the most appropriate antibiotic to administer in this scenario from the choices available?
Your Answer:
Correct Answer: Give IM benzylpenicillin 600 mg
Explanation:Meningococcal septicaemia should be suspected in a child with a non-blanching rash especially in the presence of:An ill-looking childNeck stiffnessLesions larger than 2 mm in diameter (purpura)Capillary refill time of>3 secondsThe index child is very sick and shows signs of septic shock. In the prehospital setting, a single dose of benzylpenicillin should be given immediately. The correct dose for this childs age is IM benzylpenicillin 600 mg.The recommended doses of benzylpenicillin according to age are:Infants <1 year of age: IM or IV benzylpenicillin 300 mgChildren 1 to 9 years of age: IM or IV benzylpenicillin 600mgChildren and adults 10 years or older: IM or IV benzylpenicillin 1.2g
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This question is part of the following fields:
- Infections
- Pharmacology
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Question 83
Incorrect
-
A 20-year-old male has an anaphylactic reaction following a wasp sting.What type of hypersensitivity reaction is this?
Your Answer:
Correct Answer: Type I
Explanation:Anaphylaxis is an example of a type I hypersensitivity reaction. It is IgE mediated. It requires a prior exposure to the antigen. The initial exposure sensitizes the body to the antigen and a second exposure to that antigen leads to an anaphylactic reaction.Massive calcium influx into the cells leads to mast cell degranulation. The Immunoglobulin antigen complex binds to Fc receptors on the surface of mast cells. The result is mast cell degranulation and release of histamine, proteoglycans and serum proteases from cytoplasmic granules.
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This question is part of the following fields:
- General Pathology
- Pathology
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Question 84
Incorrect
-
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:
Correct 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 in the UK 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.
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This question is part of the following fields:
- Cardiovascular Pharmacology
- Pharmacology
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Question 85
Incorrect
-
A 59-year-old otherwise well woman presents with a history of polydipsia and polyuria. There is a past history of kidney stones, and blood tests done reveal the following: Na: 147 mmol/L (135-147 mmol/L) K: 4.0 mmol/L (3.5-5.5 mmol/L) Urea: 7.3 mmol/L (2.0-6.6 mmol/L) Creatinine: 126 mmol/L (75-125 mmol/L) Fasting blood glucose: 5.0 mmol/L (3.4-5.5 mmol/L) Corrected calcium: 3.21 mmol/L (2.05-2.60 mmol/L) Phosphate: 0.70 mmol/L (0.8-1.4 mmol/L) Parathyroid hormone: 189 ng/L (10-60 ng/L)The most likely diagnosis is?
Your Answer:
Correct Answer: Primary hyperparathyroidism
Explanation:​Primary hyperparathyroidism the commonest cause of hypercalcaemia. It is commonest in women aged 50 to 60.The commonest cause of primary hyperparathyroidism is a solitary adenoma of the parathyroid gland (approximately 85% of cases). Primary hyperparathyroidism may present with features of hypercalcaemia such as polyuria, polydipsia, renal stones, bone and joint pain, constipation, and psychiatric disorders.In primary Hyperparathyroidism:PTH is elevatedCalcium is elevatedPhosphate is loweredIn secondary Hyperparathyroidism:PTH is elevatedCalcium is low or low-normalPhosphate is raised in CRFIn tertiary Hyperparathyroidism:PTH is elevatedCalcium is elevatedPhosphate is lowered in CRF
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This question is part of the following fields:
- Endocrine Physiology
- Physiology
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Question 86
Incorrect
-
At rest, skeletal muscle accounts for between 15-20% of cardiac output and accounts for around 50% of body weight. This can increase to nearly 80% of cardiac output during exercise. Skeletal muscle circulation is highly controlled and has a number of specialized adaptations as a result of this high degree of disparity during exercise, in combination with the diversity in the size of skeletal muscle around the body.What is the primary mechanism for boosting skeletal muscle blood flow during exercise?
Your Answer:
Correct Answer: Metabolic hyperaemia
Explanation:In skeletal muscle, blood flow is closely related to metabolic rate. Due to the contraction of precapillary sphincters, most capillaries are blocked off from the rest of the circulation at rest and are not perfused. This causes an increase in vascular tone and vessel constriction. As metabolic activity rises, this develops redundancy in the system, allowing it to cope with greater demand. During exercise, metabolic hyperaemia, which is induced by the release of K+, CO2, and adenosine, recruits capillaries. Sympathetic vasoconstriction in the active muscles is overridden by this. Simultaneously, blood flow in non-working muscles is restricted, preserving cardiac output. During exercise, muscle contractions pump blood through the venous system, raising the pressure differential between arterioles and venules and boosting blood flow via capillaries.Capillary angiogenesis is evident when muscles are used repeatedly (e.g. endurance training). It is a long-term effect, not a quick fix for increased blood flow.The local partial pressure of alveolar oxygen is the primary intrinsic control of pulmonary blood flow (pAO2). Low pAO2 promotes arteriole vasoconstriction and vice versa. The hypoxic pulmonary vasoconstriction (HPV) reflex allows blood flow to be diverted away from poorly ventilated alveoli and towards well-ventilated alveoli in order to maximize gaseous exchange.
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This question is part of the following fields:
- Cardiovascular Physiology
- Physiology
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Question 87
Incorrect
-
The big toe of a 59-year-old female is red, hot, and swollen. The patient is diagnosed with acute gout. You intend to start her on a nonsteroidal anti-inflammatory medicine (NSAID). Her husband was diagnosed with a peptic ulcer, and she is apprehensive about the potential adverse effects of NSAIDs.Which of the following NSAIDs has the lowest chance of causing side effects?Â
Your Answer:
Correct Answer: Ibuprofen
Explanation:Non-steroidal anti-inflammatory medications (NSAIDs) have slight differences in anti-inflammatory activity, but there is a lot of diversity in individual response and tolerance to these treatments. Approximately 60% of patients will respond to any NSAID; those who do not respond to one may well respond to another. Pain relief begins soon after the first dose, and a full analgesic effect should be achieved within a week, whereas an anti-inflammatory effect may take up to three weeks to achieve (or to be clinically assessable). If the desired results are not reached within these time frames, another NSAID should be attempted.By inhibiting the enzyme cyclo-oxygenase, NSAIDs limit the generation of prostaglandins. They differ in their selectivity for inhibiting various types of cyclo-oxygenase; selective inhibition of cyclo-oxygenase-2 is linked to reduced gastrointestinal discomfort. Susceptibility to gastrointestinal effects is influenced by a number of different parameters, and an NSAID should be chosen based on the frequency of side effects.Ibuprofen is an anti-inflammatory, analgesic, and antipyretic propionic acid derivative. Although it has fewer side effects than other non-selective NSAIDs, its anti-inflammatory properties are less effective. For rheumatoid arthritis, daily doses of 1.6 to 2.4 g are required, and it is contraindicated for illnesses characterized by inflammation, such as acute gout.Because it combines strong efficacy with a low incidence of adverse effects, Naproxen is one of the top choices. It is more likely to cause negative effects than ibuprofen.Similar to ibuprofen, ketoprofen and diclofenac have anti-inflammatory characteristics, however they have additional negative effects.Indomethacin has a similar or better effect to naproxen, however it comes with a lot of side effects, such as headaches, dizziness, and gastrointestinal problems.
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This question is part of the following fields:
- Musculoskeletal Pharmacology
- Pharmacology
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Question 88
Incorrect
-
Regarding the routine childhood immunisation schedule, which of the following vaccines is given to preschool children (aged 3 years and 4 months):
Your Answer:
Correct Answer: Measles, mumps and rubella (MMR)
Explanation:The current UK childhood immunisation schedule is as follows:8 weeks:DTaP/IPV(polio)/Hib/Hep B (diptheria, tetanus, pertussis, polio,Haemophilus influenzatype b and hepatitis B) – 6-in-one injection (Infranix hexa);plus:Rotavirus gastroenteritis (Rotarix) – oral route (drops)Meningitis B (Bexsero)12 weeks:DTaP/IPV(polio)/Hib/Hep B – 2nddose: 6-in-one injection, 2nddose (Infranix hexa);plus:PCV (pneumococcal conjugate vaccine) – in a separate injection (Prevenar 13)Rotavirus gastroenteritis 2nddose (Rotarix) – oral route (drops)16 weeks:DTaP/IPV(polio)/Hib/Hep B – 3rddose: 6-in-one injection, 3rddose (Infranix hexa);plus:Meningitis B 2nddose (Bexsero)Between 12 and 13 months:Hib/Men C (combined as one injection) – 4th dose of Hib and 1stdose of Meningitis C (Menitorix);plus:MMR (measles, mumps and rubella) – combined as one injection (Priorix or M-M-RVAXPRO);plus:PCV (pneumococcal conjugate vaccine) – 2nddose in a separate injection (Prevenar 13);plus:Meningitis B 3rddose (Bexsero)From 2 to end of primary school:Nasal flu spray (Fluenz Tetra). For children aged 2,3 and 4, this is usually given in the GP surgery. Children in school years 1,2 and 3 may have this at school.3 years and 4 months:Pre-school booster of DTaP/IPV (polio) – 4-in-one injection (Repevax or Infanrix-IPV);plus:MMR – 2nd dose (Priorix or M-M-RVAXPRO) – in a separate injectionBetween 12 and 13 years:HPV (human papilloma virus types 6,11, 16 and 18) –twoinjections of Gardasil given. The second injection is given 6-24 months after the first one.14 years:Td/IPV (polio) booster – 3-in-one injection (Revaxis)Men ACWY: combined protection against meningitis A, C, W and Y (Nimenrix or Menveo)The BCG vaccination against tuberculosis is only offered to neonates in high-risk areas or with high-risk backgrounds. When required it is usually given before leaving the hospital soon after birth.
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This question is part of the following fields:
- Immunoglobulins And Vaccines
- Pharmacology
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Question 89
Incorrect
-
Regarding cross-sectional studies, which of the following statements is CORRECT:
Your Answer:
Correct Answer: They are particularly suitable for estimating point prevalence.
Explanation:Cross-sectional studies aim to provide data about population health, normal ranges of biological parameters, and disease prevalence or severity by observing the entire population, or a representative subset, at a single point in time. Cross-sectional studies are relatively simple and quick to perform and can be used to study multiple outcomes, but are subject to confounding and recall bias and are not suitable for studying rare diseases. Cross-sectional studies cannot be used to assess causation or to consider trends over time.
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This question is part of the following fields:
- Evidence Based Medicine
- Study Methodology
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Question 90
Incorrect
-
Which of the following statements is true about percutaneous needle aspiration?
Your Answer:
Correct Answer: The needle should be inserted just above the upper border of the chosen rib
Explanation:Pleural aspiration describes a procedure whereby pleural fluid or air may be aspirated via a system inserted temporarily into the pleural space. This may be for diagnostic purposes (usually removing 20–50 ml fluid) or therapeutic to relieve symptoms. In the literature it is varyingly called thoracocentesis, thoracentesis or pleural aspiration.In determining the correct patient position and site of insertion, it is important for the operator to be aware of the normal anatomy of the thorax and the pathology of the patient. Patient position is dependent on the operator preference and the site of the pathology. In the case of a posterior lying locule, this may be specific to the image-guided spot where fluid is most likely to be obtained. In most circumstances, however, the site of insertion of the needle is either in the triangle of safety or the second intercostal space in the midclavicular line. The patient may therefore either sit upright leaning forward with arms elevated but resting on a table or bed, thereby exposing the axilla, or lying on a bed in a position. The needle is inserted in the space just above the chosen rib to avoid damaging the neurovascular bundle. It is common practice to insert the needle more posteriorly for a pleural aspiration, but it should be noted that the neurovascular bundle may not be covered by the lower flange of the rib in this position and a more lateral or anterior site of insertion is considered safer.
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This question is part of the following fields:
- Anatomy
- Thorax
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Question 91
Incorrect
-
What is the interquartile range for these numbers: 11, 4, 6, 8, 3, 10, 8, 10, 4, 12, 31?
Your Answer:
Correct Answer: 7
Explanation:We obtain 3, 4, 4, 6, 8, 8, 10, 11, 12, and 31, and sample size (n) = 11 when we order the data. [(n+1)/2] = median 6th value = (11+1)/2 = [(n+1)/4] represents the bottom (first) quartile. (3rd value = 4th value = (11 + 1)/4 3[(n+1)/4] for the top (third) quartile 3[(11 + 1)/4] = 9th value = 11th value = 11th value = 11th value = 11th value = 11th value = 11th value = 11th value = 11th The difference between the upper and lower quartiles is the interquartile range, which is equal to 11 minus 4 = 7.
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This question is part of the following fields:
- Evidence Based Medicine
- Statistics
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Question 92
Incorrect
-
A 50-year-old man presents with signs and symptoms of an anaphylactic reaction. His GP had recently given him a new medication.Which one of these is the most likely medication responsible for the drug-induced anaphylactic reaction?
Your Answer:
Correct Answer: Penicillin
Explanation:The most common cause of drug-induced anaphylaxis is penicillin.The second commonest cause are NSAIDs. Other drugs associated with anaphylaxis are ACE inhibitors and aspirin.
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This question is part of the following fields:
- Infections
- Pharmacology
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Question 93
Incorrect
-
A 57-year-old woman receives vitamin B12 injections following a gastrectomy.Which of the following cell types, if absent, is responsible for her vitamin B12 deficiency?
Your Answer:
Correct Answer: Parietal cells
Explanation:Intrinsic factor, produced by the parietal cells of the stomach, is essential for the absorption of vitamin B12 from the terminal ileum. After a gastrectomy, the absorption of vitamin B12 is markedly reduced, and a deficiency will occur.
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This question is part of the following fields:
- Gastrointestinal Physiology
- Physiology
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Question 94
Incorrect
-
Regarding linear relationships between two variables, what does a positive correlation coefficient indicate:
Your Answer:
Correct 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.
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This question is part of the following fields:
- Evidence Based Medicine
- Statistics
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Question 95
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:
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.
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This question is part of the following fields:
- Anatomy
- Lower Limb
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Question 96
Incorrect
-
A 17-year-old type I diabetic patient presents with abdominal pain and vomiting. Measurement of her blood glucose level is done and found to be grossly elevated. She is diagnosed with diabetic ketoacidosis. A fixed rate insulin infusion is given as part of her treatment.Which of these is an action of insulin?
Your Answer:
Correct Answer: Stimulates lipogenesis
Explanation:Insulin is an anabolic hormone. Its actions can be broadly divided into:Lipid metabolismProtein metabolism andCarbohydrate metabolismFor lipid metabolism, insulin:Stimulates lipogenesisInhibits lipolysis by lipaseFor carbohydrate metabolism, insulin:Decreases gluconeogenesisStimulates glycolysisPromotes glucose uptake in muscle and adipose tissuePromotes glycogen storageIncreases glycogenesisDecreases glycogenolysisProtein metabolism:Stimulates protein synthesisAccelerates net formation of proteinStimulates amino acid uptakeInhibits protein degradationInhibits amino acid conversion to glucose
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This question is part of the following fields:
- Endocrine Physiology
- Physiology
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Question 97
Incorrect
-
Regarding atracurium, which of the following statements is CORRECT:
Your Answer:
Correct Answer: Effects such as flushing, tachycardia and hypotension can occur due to significant histamine release.
Explanation:Cardiovascular effects such as flushing, tachycardia, hypotension and bronchospasm are associated with significant histamine release; histamine release can be minimised by administering slowly or in divided doses over at least 1 minute. Atracurium undergoes non-enzymatic metabolism which is independent of liver and kidney function, thus allowing its use in patients with hepatic or renal impairment. Atracurium has no sedative or analgesic effects. All non-depolarising drugs should be used with care in patients suspected to be suffering with myasthenia gravis or myasthenic syndrome, as patients with these conditions are extremely sensitive to their effects and may require a reduction in dose.
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This question is part of the following fields:
- Anaesthesia
- Pharmacology
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Question 98
Incorrect
-
The patient is a 66-year-old woman who has troublesome bilateral ankle swelling. This has been happening since she began taking a new antihypertensive medication a few weeks ago.Which of the following medications is most likely to be the cause of this adverse reaction?
Your Answer:
Correct Answer: Amlodipine
Explanation:Amlodipine is a calcium-channel blocker that is frequently used to treat hypertension. Ankle swelling is a very common side effect of calcium-channel blockers, and it occurs quite frequently.
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This question is part of the following fields:
- Cardiovascular Pharmacology
- Pharmacology
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Question 99
Incorrect
-
A patient presents with a rash for dermatological examination. A large area of purplish discolouration of the skin that measures 2 cm in diameter and does not blanch when pressure is applied is seen .What is the best description of this rash that you have found on examination?
Your Answer:
Correct Answer: Ecchymoses
Explanation:Ecchymosis are discolouration of the skin or mucous membranes caused by extravasation of blood. They are usually red or purple in colour and measure greater than 1 cm in diameter and do not blanch on applying pressure. 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. Petechiae are discolouration of the skin measuring less than 3 mm in diameterPurpura are discolouration of the skin measuring between 0.3 cm and 1 cm in diameter.Erythema is redness of the skin or mucous membranes caused by hyperaemia of superficial capillaries caused by skin injury, infection or inflammation. Erythema blanches when pressure is applied whereas ecchymosis, purpura and petechiae do not.
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This question is part of the following fields:
- General Pathology
- Pathology
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Question 100
Incorrect
-
Hepatitis A is transmitted by which of the following routes:
Your Answer:
Correct Answer: Faecal-oral route
Explanation:Hepatitis A transmission is by the faecal-oral route; the virus is excreted in bile and shed in the faeces of infected people.
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This question is part of the following fields:
- Microbiology
- Pathogens
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Question 101
Incorrect
-
Regarding saliva, which of the following statements is CORRECT:
Your Answer:
Correct Answer: Saliva production is decreased by inhibition of the parasympathetic nervous system.
Explanation:At rest, saliva is predominantly produced by the submandibular gland (65%) but when stimulated, the parotid glands produce a higher proportion of the total saliva production (50%) than at rest. Saliva is alkaline and hypotonic to plasma. The predominant digestive enzymes in saliva are alpha-amylase and lingual lipase; lingual lipase is not functionally very important, but alpha-amylase is important for the initiation of starch digestion. Saliva production is decreased by inhibition of the parasympathetic nervous system e.g. by sleep, dehydration, anticholinergic drugs and fear.
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This question is part of the following fields:
- Gastrointestinal
- Physiology
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Question 102
Incorrect
-
A 40-year-old man who has a history of asthma arrives at the emergency department complaining of palpitations that have been going on for 5 days. Which of the following beta-blockers is the safest for an asthmatic patient?
Your Answer:
Correct Answer: Atenolol
Explanation:Atenolol is a beta blocker, which is a type of medication that works by preventing certain natural substances in the body, such as epinephrine, from acting on the heart and blood vessels. This effect reduces heart rate, blood pressure, and cardiac strain. Atenolol, bisoprolol fumarate, metoprolol tartrate, nebivolol, and (to a lesser extent) acebutolol have a lower action on beta2 (bronchial) receptors and are thus cardio selective but not cardiac specific. They have a lower effect on airway resistance, although they are not without this adverse effect.
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This question is part of the following fields:
- Cardiovascular
- Pharmacology
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Question 103
Incorrect
-
Which of the following conditions manifests hyperkalaemia as one of its symptoms?
Your Answer:
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 104
Incorrect
-
All of the following statements regarding metronidazole are correct except:
Your Answer:
Correct Answer: Metronidazole reduces the anticoagulant effect of warfarin.
Explanation:The anticoagulant effect of warfarin is enhanced by metronidazole. If use of both cannot be avoided, one must consider appropriately reducing the warfarin dosage. With alcohol, metronidazole can cause a disulfiram-like reaction, with symptoms like flushing, headaches, dizziness, tachypnoea and tachycardia, nausea and vomiting. The common side effects of metronidazole include a metallic taste and gastrointestinal irritation, in particular nausea and vomiting. These side effects are more common at higher doses. This drug has high activity against anaerobic bacteria and protozoa, and is well absorbed orally. For severe infections, the intravenous route is normally reserved.
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This question is part of the following fields:
- Infections
- Pharmacology
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Question 105
Incorrect
-
Which of the following is NOT a benefit of low molecular weight heparin (LMWH) over unfractionated heparin therapy:
Your Answer:
Correct Answer: Its effects can be rapidly and completely reversed with protamine sulfate.
Explanation:Advantages of LMWHGreater ability to inhibit factor Xa directly, interacting less with platelets and so may have a lesser tendency to cause bleedingGreater bioavailability and longer half-life in plasma making once daily subcutaneous administration possibleMore predictable dose response avoiding the need for routine anticoagulant monitoringLower associated risk of heparin-induced thrombocytopenia or of osteoporosis
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This question is part of the following fields:
- Cardiovascular
- Pharmacology
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Question 106
Incorrect
-
A 29-year-old man presents with painful red eye with copious discharge and you make a diagnosis of infective conjunctivitis following a history and an examination,.One of these is NOT an indication for an urgent ophthalmology referral in this patient.
Your Answer:
Correct Answer: Bilateral conjunctivitis
Explanation:Urgent referral to ophthalmology is indicated if the patient with conjunctivitis has any of the following:Suspected gonococcal or chlamydial conjunctivitisCorneal involvement associated with soft contact lens useSevere disease indicated by presence of a pseudomembraneConjunctivitis associated with rheumatoid arthritis or in immunocompromised patient. Ophthalmia neonatorum.Possible herpes infection.Had recent intraocular surgery. A red flag indicating a serious cause of red eye.Suspected periorbital or orbital cellulitis.Bilateral conjunctivitis is not an indication for urgent referral to ophthalmology.
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This question is part of the following fields:
- Microbiology
- Specific Pathogen Groups
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Question 107
Incorrect
-
Question 108
Incorrect
-
Regarding endothelin-1, which of the following statements is INCORRECT:
Your Answer:
Correct Answer: Endothelin-1 release is inhibited by noradrenaline.
Explanation:Endothelin-1 (ET-1) is an extremely potent vasoconstrictor peptide which is released from the endothelium in the presence of many other vasoconstrictors, including angiotensin II, antidiuretic hormone (ADH) and noradrenaline, and may be increased in disease and hypoxia.
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This question is part of the following fields:
- Cardiovascular
- Physiology
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Question 109
Incorrect
-
Regarding relationships between two variables, what does a negative correlation coefficient indicate:
Your Answer:
Correct Answer: The two variables are inversely related
Explanation:A negative correlation coefficient means that the two variables are inversely related e.g. socio-economic class and mortality.
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This question is part of the following fields:
- Evidence Based Medicine
- Statistics
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Question 110
Incorrect
-
What is the mechanism of action of penicillin antibiotics:
Your Answer:
Correct Answer: Inhibition of bacterial cell wall synthesis
Explanation:Penicillins and the other ß-lactam antibiotics are bactericidal. They produce their antimicrobial action by preventing cross-linkage between the linear peptidoglycan polymer chains that make up the bacterial cell wall. They, therefore, inhibit cell wall synthesis.The integrity of the ß-lactam ring is essential for antimicrobial activity. Many bacteria (including most Staphylococci) are resistant to benzylpenicillin and phenoxymethylpenicillin because they produce enzymes (penicillinases, ß-lactamases) that open the ß-lactam ring.
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This question is part of the following fields:
- Infections
- Pharmacology
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Question 111
Incorrect
-
In the Paediatric Emergency Department, you saw a 6-year-old girl with severe bilateral conjunctivitis. You give her mother some general eye hygiene advice and prescribe chloramphenicol eye drops.What is the chloramphenicol's mechanism of action?
Your Answer:
Correct Answer: Inhibition of protein synthesis
Explanation:Chloramphenicol is a broad-spectrum antibiotic that inhibits bacterial protein synthesis by blocking the 50S subunit of the bacterial ribosome’s peptidyl transferase activity. When administered systemically, it has limited usage due to the potential of significant side effects such as aplastic anaemia, peripheral neuropathy, and optic neuritis. It’s only used to treat typhoid fever and Haemophilus influenzae meningitis, but it’s usually better to use a broad-spectrum cephalosporin.
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This question is part of the following fields:
- Infections
- Pharmacology
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Question 112
Incorrect
-
In a VF arrest, a 6-year-old child is brought to your Emergency Department resuscitation area. He weighs 16 kilogrammes. He's had three DC shocks, but he's still in VF and doesn't have an output.What amiodarone dose should he get now, according to the most recent APLS guidelines?
Your Answer:
Correct Answer: 80 mg
Explanation:In a shockable (Vf/pVT) paediatric cardiac arrest, amiodarone should be administered after the third and fifth shocks. The dose is 5 mg/kg (maximum 300 mg) and should be administered over a three-minute period. If at all possible, administration via a central line is recommended.
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This question is part of the following fields:
- Cardiovascular Pharmacology
- Pharmacology
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Question 113
Incorrect
-
Regarding inhaled corticosteroids, which of the following statements is INCORRECT:
Your Answer:
Correct Answer: Lower doses of inhaled corticosteroids may be required in smokers.
Explanation:Current and previous smoking reduces the effectiveness of inhaled corticosteroids and higher doses may be necessary.
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This question is part of the following fields:
- Pharmacology
- Respiratory
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Question 114
Incorrect
-
A 49-year-old man known sickle cell disease patient received a blood transfusion and developed a mild fever and dark urine 6 days after transfusion. His investigations show raised bilirubin, raised LDH, and a positive Direct Antiglobulin Test (DAT).Which transfusion reaction is most likely occurred?
Your Answer:
Correct Answer: Delayed haemolytic reaction
Explanation:Delayed haemolytic transfusion reactions (DHTRs) commonly occurs 4-8 days after blood transfusion, but can occur up to a month after. Signs and symptoms include jaundice, fever, an inadequate rise in PCV, reticulocytosis, a positive antibody screen and a positive Direct Antiglobulin Test (Coombs test). DHTRs usually have a benign course and require no treatment but sometimes, life-threatening haemolysis with severe anaemia and renal failure can occur so haemoglobin levels and renal function should be monitored.Acute haemolytic reaction aka immediate haemolytic transfusion reaction presents with fever, chills, pain at transfusion site, nausea, vomiting, dark urine and feeling of ‘impending doom’. Often, it occurs due to ABO incompatibility.Febrile transfusion reaction presents with a 1 degree rise in temperature from baseline during transfusion. Patient may have chills and malaise. It is the most common transfusion reaction (1 in 8 transfusions) and is usually caused by cytokines released from leukocytes in transfused red cell or platelet components.Transfusion-associated circulatory overload (TACO) presents as acute or worsening respiratory distress within 6 hours of transfusion of a large volume of blood. It is common in patients with diminished cardiac reserve or chronic anaemia. Elderly patients, infants and severely anaemic patients are particularly susceptible. Clinical features of TACO include: Acute respiratory distress, Tachycardia, Hypertension, Acute/worsening pulmonary oedema on chest X-ray. The BNP is usually raised to at least 1.5 times the pre-transfusion baseline.Graft versus host disease(GVHD) is an immune mediated condition that arises from a complex interaction between donor and recipients adaptive immunity. It presents as dermatitis, hepatitis and enteritis developing within 100 days after stem cell or bone marrow transplant.
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This question is part of the following fields:
- Haematology
- Pathology
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Question 115
Incorrect
-
Stimulation of J receptors located on alveolar and bronchial walls results in all of the following EXCEPT for:
Your Answer:
Correct Answer: Tachycardia
Explanation:Juxtapulmonary or ‘J’ receptors are located on alveolar and bronchial walls close to the capillaries. Their afferents are small unmyelinated C-fibres or myelinated nerves in the vagus nerve. Activation causes depression of somatic and visceral activity by producing apnoea or rapid shallow breathing, a fall in heart rate and blood pressure, laryngeal constriction and relaxation of skeletal muscles via spinal neurones. J receptors are stimulated by increased alveolar wall fluid, pulmonary congestion and oedema, microembolism and inflammatory mediators. J receptors are thought to be involved in the sensation of dyspnoea in lung disease.
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This question is part of the following fields:
- Physiology
- Respiratory
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Question 116
Incorrect
-
A young man develops an infection spread via aerosol transmission.Which of these organisms is commonly spread by aerosol transmission?
Your Answer:
Correct Answer: Measles virus
Explanation:Aerosols are airborne particles less than 5 µm in size, containing infective organisms that usually cause infection of the upper or lower respiratory tract.Examples of organisms commonly spread by aerosol transmission are:Measles virusVaricella zoster virusMycobacterium tuberculosisThe following table summarises the various routes of transmission with example organisms:Route of transmissionExample organismsAerosol (airborne particle < 5 µm)Mycobacterium tuberculosisVaricella zoster virusMeasles virusHepatitis A and Rotavirus are spread by the faeco-oral route.Neisseria gonorrhoea is spread by sexual route.Staphylococcus aureus is spread by direct contact.
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This question is part of the following fields:
- Microbiology
- Principles Of Microbiology
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Question 117
Incorrect
-
Regarding carbon dioxide transport in the blood, which of the following statements is CORRECT:
Your Answer:
Correct Answer: Deoxygenated haemoglobin acts as a buffer for H+ ions.
Explanation:CO2generated in the tissues and water combine to form carbonic acid which readily dissociates to form HCO3-and H+. The first part of this reaction is very slow in plasma, but is accelerated dramatically by the enzyme carbonic anhydrase present in red blood cells. Bicarbonate is therefore formed preferentially in red cells, from which it freely diffuses down its concentration gradient into plasma where it is transported to the lungs. The red cell membrane is impermeable to H+ions which remain in the cell. To maintain electroneutrality, Cl-ions diffuse into the cell to replace HCO3-, an effect known as the chloride shift. Deoxygenated haemoglobin acts as a buffer for H+, allowing the reaction to continue.
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This question is part of the following fields:
- Physiology
- Respiratory
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Question 118
Incorrect
-
Bendoflumethiazide may cause all of the following electrolyte imbalances EXCEPT for:
Your Answer:
Correct Answer: Hypocalcaemia
Explanation:Common side effects of thiazide diuretics include:Excessive diuresis, postural hypotension, dehydration, renal impairmentAcid-base and electrolyte imbalanceHypokalaemia, hyponatraemia, hypomagnesaemia, hypercalcaemia, hypochloraemic alkalosisMetabolic imbalanceHyperuricaemia and goutImpaired glucose tolerance and hyperglycaemiaAltered plasma-lipid concentrationsMild gastrointestinal disturbances
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This question is part of the following fields:
- Cardiovascular
- Pharmacology
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Question 119
Incorrect
-
The ventilation over perfusion ratio is highest at the apex of the lung. What is the approximate V/Q ratio at this area?
Your Answer:
Correct Answer: 3.3
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.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. The V/Q ratio is also affected by location. The various areas of the lungs have a different V/Q ratio since ventilation and perfusion increase from the apex to the base of the lungs. The apex of the lungs has a V/Q ratio of approximately 3.3.
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This question is part of the following fields:
- Physiology
- Respiratory Physiology
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Question 120
Incorrect
-
If a patient dislocated his right shoulder and has been referred to the orthopaedic outpatient department for a follow-up after a successful reduction, which of the following is the most important position for him to avoid holding his arm in until he is seen in the clinic?
Your Answer:
Correct Answer: Arm at 90 degrees to side with palm up
Explanation:The arm should be placed in a poly-sling that should be worn for about two weeks. A physiotherapist may give gentle movements for the arm to help in reducing stiffness and in relieving the pain. It is important that the patient must avoid positions that could cause re-dislocation.The most important position to avoid is the arm being held out at 90 degrees to the side with the palm facing upwards, especially if a force is being applied.
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This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 121
Incorrect
-
Which of the following terms describes the proportion of individuals with a negative test result who actually do not have a disease:
Your Answer:
Correct Answer: Negative predictive value
Explanation:Negative predictive value (NPV) is the proportion of individuals with a negative test result who do not have the disease.NPV = d/(c+d)
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This question is part of the following fields:
- Evidence Based Medicine
- Statistics
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Question 122
Incorrect
-
Regarding penicillin antibiotics, which of the following statements is CORRECT:
Your Answer:
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 123
Incorrect
-
Which of the following is NOT a typical effect of cortisol:
Your Answer:
Correct Answer: Decreased protein catabolism
Explanation:Cortisol is a steroid hormone produced in the zona fasciculata of the adrenal cortex. It is released in response to stress and low blood glucose concentrations.Cortisol acts to: raise plasma glucose by stimulating glycolysis and gluconeogenesis in the liver and inhibiting peripheral glucose uptake into storage tissues, increase protein breakdown in skeletal muscle, skin and bone to release amino acids, increase lipolysis from adipose tissues to release fatty acidsand at higher levels and mimic the actions of aldosterone on the kidney to retain Na+ and water and lose K+ ionssuppress the action of immune cells
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This question is part of the following fields:
- Endocrine
- Physiology
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Question 124
Incorrect
-
A 37-year-old man presents with breathlessness on exertion and dry cough, fever for the past 2 days and bilateral pleuritic chest pain. He had been diagnosed with HIV and commenced on HAART but due to side effects, his compliance has been poor over the last few months.On examination you note scattered crackles and wheeze bilaterally, cervical and inguinal lymphadenopathy, and oral thrush. At rest his oxygen saturation is 97% but this drops to 87% on walking. There is perihilar fluffy shadowing seen on his chest X-ray.Which of these organisms is the most likely causative organism?
Your Answer:
Correct Answer: Pneumocystis jirovecii
Explanation:All of the organisms listed above can cause pneumonia in immunocompromised individuals but the most likely cause in this patient is Pneumocystis jirovecii.It is a leading AIDS-defining infection in HIV-infected individuals and causes opportunistic infection in immunocompromised individuals. HIV patients with a CD4 count less than 200 cells/mm3 are more prone.The clinical features of pneumonia caused by Pneumocystis jirovecii are:Fever, chest pain, cough (usually non-productive), exertional dyspnoea, tachypnoea, crackles and wheeze.Desaturation on exertion is a very sensitive sign of Pneumocystis jirovecii pneumonia.Chest X-ray can show perihilar fluffy shadowing (as is seen in this case) but can also be normal.
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This question is part of the following fields:
- Microbiology
- Specific Pathogen Groups
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Question 125
Incorrect
-
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:
Correct 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.
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This question is part of the following fields:
- Microbiology
- Principles Of Microbiology
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Question 126
Incorrect
-
Which of the following is NOT a function of the commensal intestinal bacterial flora:
Your Answer:
Correct Answer: Breakdown of haem into bilirubin
Explanation:Commensal intestinal bacterial flora have a role in:Keeping pathogenic bacteria at bay by competing for space and nutrientConverting conjugated bilirubin to urobilinogen (some of which is reabsorbed and excreted in urine) and stercobilinogen which is excreted in the faecesThe synthesis of vitamins K, B12, thiamine and riboflavinThe breakdown of primary bile acids to secondary bile acidsThe breakdown of cholesterol, some food additives and drugs
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This question is part of the following fields:
- Gastrointestinal
- Physiology
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Question 127
Incorrect
-
A young farmer who is caught under farm machinery and suffering from a major crush injury is taken to the emergency department and requires a quick induction sequence. In this type of injury, which of the following anaesthetic medicines should be avoided?
Your Answer:
Correct Answer: Suxamethonium
Explanation:Suxamethonium is a neuromuscular blocker. It is contraindicated in patients who have experienced massive trauma, hyperkalemic, or burn injuries.
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This question is part of the following fields:
- Anaesthesia
- Pharmacology
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Question 128
Incorrect
-
External haemorrhoids may cause anal pain. When explaining to your patient why it does so, which of the following nerves will you point out as being affected?
Your Answer:
Correct Answer: Pudendal nerve
Explanation:The pain associated with external haemorrhoids is carried by a branch of the pudendal nerve, specifically the somatic fibres (S2-S4). It innervates the external anal sphincter and most of the skin over the perineum.
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This question is part of the following fields:
- Abdomen
- Anatomy
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Question 129
Incorrect
-
An ambulance transports a 23-year-old woman who has taken a witnessed overdose of her mother's diazepam tablets. She has no significant medical history and does not take any medications on a regular basis.In this case, what is the SINGLE MOST APPROPRIATE FIRST DRUG TREATMENT?
Your Answer:
Correct Answer: Flumazenil IV 200 μg
Explanation:Flumazenil is a benzodiazepine antagonist that can be helpful in some overdose situations. It works quickly (in less than a minute), but the effects are fleeting, lasting less than an hour. The dose is 200 micrograms every 1-2 minutes with a maximum dose of 3 milligrams per hour.Flumazenil should be avoided by patients who are addicted to benzodiazepines or who take tricyclic antidepressants because it can cause withdrawal symptoms. It can cause seizures or cardiac arrest in these situations.
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This question is part of the following fields:
- CNS Pharmacology
- Pharmacology
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Question 130
Incorrect
-
A 70-year-old man has a resting tremor, rigidity, bradykinesia, and a shuffling gait. Parkinson's disease is caused by one of the following mechanisms:
Your Answer:
Correct Answer: Loss of dopaminergic neurons in the substantia nigra
Explanation:Parkinson’s disease (PD) is one of the most common neurologic disorders, affecting approximately 1% of individuals older than 60 years and causing progressive disability that can be slowed but not halted, by treatment. The 2 major neuropathologic findings in Parkinson’s disease are loss of pigmented dopaminergic neurons of the substantia nigra pars compacta and the presence of Lewy bodies and Lewy neurites. See the images below.
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This question is part of the following fields:
- Anatomy
- Central Nervous System
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Question 131
Incorrect
-
A 70-year-old patient develops bacteraemia following peripheral cannulation.Which of these bacteria is the most likely cause of the infection?
Your Answer:
Correct Answer: Staphylococcus epidermidis
Explanation:The commonest implicated organisms in hospital-acquired bacteraemia following cannulation are Staphylococcus aureus and Staphylococcus epidermidis. The risk is directly proportional to the length of time in-situ. Peripheral cannula should be replaced after 48 hours.
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This question is part of the following fields:
- Microbiology
- Principles Of Microbiology
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Question 132
Incorrect
-
A 61-year-old man complains of crushing chest pain that radiates to his left arm and jaw. An ECG is taken, and the lateral leads show extensive ST depression. His blood pressure is currently 190/123 mmHg, and as part of his treatment, you intend to begin drug therapy to lower it.Which of the following is the INITIAL drug treatment for this patient's BP reduction?
Your Answer:
Correct Answer: Glyceryl trinitrate
Explanation:End-organ damage (e.g. encephalopathy, intracranial haemorrhage, acute myocardial infarction or ischaemia, dissection, pulmonary oedema, nephropathy, eclampsia, papilledema, and/or angiopathic haemolytic anaemia) characterises a hypertensive emergency (also known as ‘accelerated hypertension’ or malignant hypertension’ It’s a life-threatening condition that necessitates rapid blood pressure reduction to avoid end-organ damage and a negative outcome.In the presence of cardiac ischaemia, hypertensive emergencies require immediate treatment to prevent myocardial infarction. Similarly, if myonecrosis occurs in the presence of an existing infarction, prompt treatment is required to prevent further myonecrosis. When thrombolysis is used as the primary reperfusion therapy for acute myocardial infarction, blood pressure control is especially important.An intravenous nitrate is the drug of choice in this situation (e.g. GTN). These have a dual purpose in that they can help patients with ischaemic chest pain manage their symptoms. Because lowering blood pressure with nitrates isn’t always enough to achieve optimal results, intravenous beta-blockers are frequently used as a supplement. For this, intravenous atenolol and metoprolol are commonly used.
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This question is part of the following fields:
- Cardiovascular Pharmacology
- Pharmacology
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Question 133
Incorrect
-
A patient suffers a lower limb fracture that causes damage to the nerve that innervates peroneus longus.Peroneus longus receives its innervation from which of the following nerves? Select ONE answer only.
Your Answer:
Correct Answer: Superficial peroneal nerve
Explanation:Peroneus brevis is innervated by the superficial peroneal nerve.Peroneus longus is innervated by the superficial peroneal nerve.Peroneus tertius is innervated by the deep peroneal nerve.
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This question is part of the following fields:
- Anatomy
- Lower Limb
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Question 134
Incorrect
-
Since the fluid that enters the loop of Henle is isotonic, what is its estimated osmolality?
Your Answer:
Correct Answer: 300 mOsm
Explanation:The loop of Henle connects the proximal tubule to the distal convoluted tubule and lies parallel to the collecting ducts. It is consists of three major segments, the thin descending limb, the thin ascending limb, and the thick ascending limb. The segments are differentiated based on structure, anatomic location, and function. The main action of the loop of Henle is to recover water and sodium chloride from urine. The liquid entering the loop of Henle is a solution of salt, urea, and other substances traversed along by the proximal convoluted tubule, from which most of the dissolved components are needed by the body, particularly glucose, amino acids, and sodium bicarbonate that have been reabsorbed into the blood. This fluid is isotonic. Isotonic fluids generally have an osmolality ranging from 270 to 310 mOsm/L. With the fluid that enters the loop of Henle, it is estimated to be 300 mOsm/L. However, after passing the loop, fluid entering the distal tubule is hypotonic to plasma since it has been diluted during its passage.
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This question is part of the following fields:
- Physiology
- Renal Physiology
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Question 135
Incorrect
-
The percentage of patients with hepatitis B that develop chronic infection is about:
Your Answer:
Correct Answer: 10%
Explanation:With hepatitis B, about 90% of people will develop lifelong immunity after clearing the infection. Chronic hepatitis develops in about 10% of patients and this may be complicated by cirrhosis or hepatocellular carcinoma. There is a very high risk of chronic infection and hepatocellular carcinoma when there is congenital infection. The risk of this in healthy adults is only about 5%.
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This question is part of the following fields:
- Microbiology
- Pathogens
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Question 136
Incorrect
-
In all of the following conditions, lymphocytosis typically occurs except for:
Your Answer:
Correct Answer: Corticosteroid therapy
Explanation:In infants and young children, lymphocytosis often occurs in response to infections that would normally produce a neutrophil reaction in adults.Lymphocytosis occurs in:1. Viral infections (e.g. infectious mononucleosis, HIV, rubella, mumps, viral hepatitis, cytomegalovirus, herpes simplex or zoster)2. Bacterial infections (e.g. pertussis, tuberculosis, toxoplasmosis, syphilis)3. Chronic lymphoid leukaemias4. Acute lymphoblastic leukaemias5. Non-Hodgkin lymphoma6. Thyrotoxicosis
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This question is part of the following fields:
- Immune Responses
- Pathology
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Question 137
Incorrect
-
Compression of this nerve can cause weakness in the left leg while walking and thigh adduction weakness at the hip joint.
Your Answer:
Correct Answer: Obturator nerve
Explanation:The obturator nerve is a sensory and motor nerve that emerges from the lumbar plexus and innervates the thigh. This nerve supplies motor innervation to the medial compartment of the thigh, making it necessary for thigh adduction.
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This question is part of the following fields:
- Anatomy
- Lower Limb
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Question 138
Incorrect
-
Regarding acute lymphoblastic leukaemia (ALL), which of the following statements is CORRECT:
Your Answer:
Correct Answer: ALL is the most common malignancy of childhood.
Explanation:Acute lymphoblastic leukaemia (ALL) is caused by an accumulation of lymphoblasts in the bone marrow and is the most common malignancy of childhood. The incidence of ALL is highest at 3 – 7 years, with 75% of cases occurring before the age of 6. 85% of cases are of B-cell lineage. Haematological investigations reveal a normochromic normocytic anaemia with thrombocytopenia in most cases. The total white cell count may be decreased, normal or increased. The blood film typically shows a variable number of blast cells. The bone marrow is hypercellular with >20% blast cells.
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This question is part of the following fields:
- Haematology
- Pathology
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Question 139
Incorrect
-
The lymph drainage of the anal canal above the pectinate line is initially to the:
Your Answer:
Correct Answer: Internal iliac nodes
Explanation:Above the pectinate line, the anal canal drains to the internal iliac lymph nodes which subsequently drain to the lumbar (para-aortic) nodes.
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This question is part of the following fields:
- Abdomen
- Anatomy
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Question 140
Incorrect
-
A 22 year old male has been stabbed and is brought to the ED with a stab wound to his upper limb. On examination, the patient is unable to flex the distal interphalangeal joints of the ring and little finger. However, the proximal interphalangeal joint is intact. The most likely affected nerve is which of the following, and at which level is this occurring?
Your Answer:
Correct Answer: Ulnar nerve at elbow
Explanation:The medial half of the flexor digitorum profundus is innervated by the ulnar nerve. Paralysis of this muscle results in loss of flexion at the distal interphalangeal joint of the ring and little finger. Flexion at the proximal interphalangeal joint is preserved as this is a function of the flexor digitorum superficialis which is innervated by the median nerve. The ulnar nerve is not correct as ulnar nerve injury at the wrist would not affect the long flexors, and the injury must have been more proximal.
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This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 141
Incorrect
-
Which JVP waveform correlates to atrial systole?
Your Answer:
Correct Answer: The a wave
Explanation:JVP Waveform in Cardiac Cycle Physiology: a wave Right atrial contraction causes atrial systole (end diastole). the c wave During right isovolumetric ventricular contraction, the tricuspid valve bulges into the right atrium, resulting in isovolumetric contraction (early systole). descent by x Rapid ventricular ejection (mid systole) is caused by a combination of right atrial relaxation, tricuspid valve downward movement during right ventricular contraction, and blood ejection from both ventricles. the v-wave Ventricular ejection and isovolumetric relaxation (late systole) occur as a result of venous return filling the right atrium. y lineage Ventricular filling occurs when the tricuspid valve opens, allowing blood to flow rapidly from the right atrium to the right ventricle.
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This question is part of the following fields:
- Cardiovascular
- Physiology
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Question 142
Incorrect
-
A 68-year-old man has a very fast heartbeat' and is out of breath. He has had a heart transplant in the past. His electrocardiogram reveals supraventricular tachycardia.Which of the following is the most appropriate adenosine dose for him to receive as a first dose?
Your Answer:
Correct Answer: Adenosine 3 mg IV
Explanation:A rapid IV bolus of adenosine is given, followed by a saline flush. The standard adult dose is 6 mg, followed by 12 mg if necessary, and then another 12 mg bolus every 1-2 minutes until an effect is seen.Patients who have had a heart transplant, on the other hand, 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.
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This question is part of the following fields:
- Cardiovascular Pharmacology
- Pharmacology
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Question 143
Incorrect
-
Which of the following best describes the popliteal artery's course?
Your Answer:
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.
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This question is part of the following fields:
- Anatomy
- Lower Limb
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Question 144
Incorrect
-
Regarding nitrous oxide, which of the following statements is CORRECT:
Your Answer:
Correct Answer: Nitrous oxide may be used for maintenance of anaesthesia where its use allows reduced dosage of other agents.
Explanation:For anaesthesia, nitrous oxide is commonly used in a concentration of around 50 – 66% in oxygen in association with other inhalation or intravenous agents. Nitrous oxide cannot be used as the sole anaesthetic agent due to lack of potency, but is useful as part of a combination of drugs since it allows reduction in dosage of other agents. Exposure to nitrous oxide for prolonged periods, either by continuous or by intermittent administration, may result in megaloblastic anaemia as a result of interference with the action of vitamin B12. Nitrous oxide increases cerebral blood flow and should be avoided in patients with, or at risk of, raised intracranial pressure. Nitrous oxide may be administered by any trained personnel experienced in its use.
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This question is part of the following fields:
- Anaesthesia
- Pharmacology
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Question 145
Incorrect
-
The muscles of the soft palate (other than the tensor veli palatini) are innervated by which of the following nerves:
Your Answer:
Correct Answer: Vagus nerve
Explanation:All of the muscles of the soft palate are innervated by the vagus nerve (from the pharyngeal plexus), except for the tensor veli palatini, which is innervated by a branch of the mandibular nerve.
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This question is part of the following fields:
- Anatomy
- Head And Neck
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Question 146
Incorrect
-
Among the following microorganisms, which is considered to be transmitted by invasion of intact skin?
Your Answer:
Correct Answer: Leptospira spp.
Explanation:Rodents and domestic animals are the primary reservoirs for the Leptospira spp, although other animals, including cows, horses, mongooses, and frogs, can also harbour the leptospires. Humans may be directly infected from animal urine or indirectly by contact with soil or water that is contaminated with urine from infected animals. Infected humans can shed leptospires in urine for up to 11 months, infected cows for 3.5 months, infected dogs for 4 years, and infected rodents possibly for their entire lifetime.The organisms enter the host through mucous membranes or abraded skin. The incubation period ranges from 5 to 14 days.
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This question is part of the following fields:
- Microbiology
- Principles Of Microbiology
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Question 147
Incorrect
-
Regarding gas gangrene, which of the following statements is CORRECT:
Your Answer:
Correct Answer: Infection is characterised by rapidly spreading tissue myonecrosis with crepitus.
Explanation:Gas gangrene usually occurs within 3 days of injury, and is characterised by pain, rapidly spreading oedema, myositis, necrosis, palpable crepitus and systemic toxicity. Diagnosis is clinical and laboratory confirmation should not delay urgent surgical intervention. Hyperbaric oxygen therapy can be considered in addition to surgery and antibiotic therapy, to stop toxin production and inhibit bacteria from replicating and spreading (as Clostridium spp. are obligate anaerobes).
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This question is part of the following fields:
- Microbiology
- Pathogens
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Question 148
Incorrect
-
A novel anti-tuberculosis medicine was compared to standard treatment and shown to cut the risk of death from 30 to 10 per 1000 people. How many patients would need to be treated (number need to treat (NNT)) in order to prevent ten additional tuberculosis deaths:
Your Answer:
Correct Answer: 500
Explanation:The risk of mortality in the control group (usual therapy) minus the risk of death in the treatment group equals the absolute risk reduction (ARR) of treatment.30/1000 minus 10/1000 = 20/1000 = 0.02NNT = 1/ARR = 1/0.02 = 50As a result, 50 people would need to be treated in order to prevent one additional fatality, and 500 people would need to be treated in order to avoid 10 additional deaths.
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This question is part of the following fields:
- Evidence Based Medicine
- Statistics
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Question 149
Incorrect
-
After collapsing in his nursing home, a 70-year-old man is brought into the ER. He is a known case of diabetes mellitus and is on medication for it. An RBS of 2.5 mmol/L (3.9-5.5 mmol/L) is recorded in the ER. Out of the following, which medication for diabetes mellitus is MOST likely responsible for his hypoglycaemic episode?
Your Answer:
Correct Answer: Pioglitazone
Explanation:Pioglitazone is used to treat type 2 diabetes mellitus. It selectively stimulates the nuclear receptor peroxisome proliferator-activated receptor gamma (PPAR-γ) and to a lesser extent PPAR-α. Of the medications mentioned in this question, only pioglitazone is a recognized cause of hypoglycaemia.
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This question is part of the following fields:
- Endocrine Pharmacology
- Pharmacology
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Question 150
Incorrect
-
You are taking care of a 55-year-old male patient with a direct inguinal hernia. In explaining his hernia, which of the following layers was compromised and had resulted in his condition?
Your Answer:
Correct Answer: Transversalis fascia
Explanation:Direct inguinal hernias are most often caused by a weakness in the muscles of the abdominal wall that develops over time, or are due to straining or heavy lifting. A direct inguinal hernia protrudes through the Transversalis fascia.
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This question is part of the following fields:
- Abdomen
- Anatomy
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Question 151
Incorrect
-
Innate, or non-specific, immunity is the immune system we are born with.Which of the following is NOT an example of innate immunity? Select ONE answer only.
Your Answer:
Correct Answer: T-lymphocytes
Explanation:Innate, or non-specific, immunity is the immune system we are born with.There are three aspects of innate immunity:1. Anatomical barriers, such as:The cough reflexEnzymes in tears and skin oilsMucus – which traps bacteria and small particlesSkinStomach acid2. Humoral barriers, such as:The complement systemInterleukin-13. Cellular barriers, such as:NeutrophilsMacrophagesDendritic cellsNatural killer cellsAntibody production is part of the specific, or inducible immune response. T-lymphocytesare responsible for the cell mediated immune response which is part of specific, or inducible immunity.
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This question is part of the following fields:
- General Pathology
- Pathology
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Question 152
Incorrect
-
Regarding T helper cells, which of the following statements is CORRECT:
Your Answer:
Correct Answer: They form the vast majority (about 75%) of the total circulating T-cell population.
Explanation:CD4+ T-cells (Helper T cells)Recognise antigen only in association with HLA class II molecules (found on antigen presenting cells (APCs) e.g. dendritic cells, B-cells; present exogenous antigens that have been phagocytosed/endocytosed into intracellular vesicles)Form most of the circulating T-cell population (about 75%)Secrete cytokines (e.g. IFN-gamma) which are required for recruitment and activation of other immune cells such as macrophages, T cytotoxic cells and NK cells and for the activation of and production of immunoglobulin from B-cells
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This question is part of the following fields:
- Immune Responses
- Pathology
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Question 153
Incorrect
-
A 72 year old man is brought to ED by ambulance with sudden onset chest pain, palpitations and shortness of breath. His HR is 160 bpm and BP 90/65. ECG demonstrates new-onset fast atrial fibrillation. Which of the following is the first-line treatment option in this case:
Your Answer:
Correct Answer: Synchronised DC cardioversion
Explanation:All patients with adverse features suggesting life-threatening haemodynamic instability (shock, syncope, heart failure, myocardial ischaemia) caused by new onset atrial fibrillation should undergo emergency electrical cardioversion with synchronised DC shock without delaying to achieve anticoagulation.
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This question is part of the following fields:
- Cardiovascular
- Pharmacology
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Question 154
Incorrect
-
Pancreatic ductal alkaline fluid secretion is mainly stimulated by which of the following hormones:
Your Answer:
Correct Answer: Secretin
Explanation:Pancreatic exocrine secretion is controlled by:Parasympathetic stimulation which enhances secretion of both the enzyme and aqueous componentsSympathetic stimulation which inhibits pancreatic secretionSecretin which stimulates secretion of the alkaline-rich fluid from ductal cellsCholecystokinin which stimulates secretion of the enzyme-rich fluid from acinar cellsSomatostatin which inhibits secretion from both acinar and ductal cellsGastrin which stimulates pancreatic acinar cells to secrete digestive enzymes
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This question is part of the following fields:
- Gastrointestinal
- Physiology
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Question 155
Incorrect
-
An outbreak of acute pneumonia occurs in military recruits living in one barrack and only in those persons located near the air conditioner. Epidemiologic surveillance results in isolation of the causal organism from the patients and from the drip pans of the air conditioner. The organism is weakly Gram-negative. The most likely organism is:
Your Answer:
Correct Answer: Legionella pneumophila
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 daysCough (usually non-productive and occurs in approximately 90%)Pleuritic chest painHaemoptysisHeadacheNausea, vomiting and diarrhoeaAnorexiaLegionella 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.
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This question is part of the following fields:
- Microbiology
- Pathogens
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Question 156
Incorrect
-
Regarding Clostridium species, which of the following statements is INCORRECT:
Your Answer:
Correct Answer: They are facultative anaerobes.
Explanation:Clostridium spp. are obligatory anaerobic spore-forming Gram-positive bacilli. Toxin production is the main pathogenicity mechanism.
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This question is part of the following fields:
- Microbiology
- Pathogens
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Question 157
Incorrect
-
An X-ray of a 24-year-old female hockey player who arrives at the hospital with a left foot injury reveals an avulsion fracture of the fifth metatarsal tuberosity. Which of the following muscles is most likely responsible for the movement of the fractured fragment?
Your Answer:
Correct Answer: Fibularis brevis
Explanation:An avulsion fracture of the base of the fifth metatarsal happens when the ankle is twisted inwards. When the ankle is twisted inwards a muscle called the fibularis brevis contracts to stop the movement and protect the ligaments of the ankle. The base of the fifth metatarsal is where this muscle is attached. The group of lateral leg muscles that function to plantarflex the foot includes the fibularis brevis and the fibularis longus.
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This question is part of the following fields:
- Anatomy
- Lower Limb
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Question 158
Incorrect
-
C3 deficiency leads to particular susceptibility of infection with which of the following:
Your Answer:
Correct Answer: Encapsulated bacteria
Explanation:Macrophages and neutrophils have C3b receptors and they phagocytose C3b-coated cells. C3 deficiency thus leads to increased susceptibility of infection with encapsulated organisms (e.g. S. pneumoniae, H. influenzae).The early stages of the complement cascade leading to coating of the cells with C3b can occur by two different pathways:The classical pathway usually activated by IgG or IgM coating of cellsThe alternative pathway which is more rapid and activated by IgA, endotoxin and other factors
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This question is part of the following fields:
- Immune Responses
- Pathology
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Question 159
Incorrect
-
Which of the following nerves innervates the adductor brevis?
Your Answer:
Correct Answer: Obturator nerve
Explanation:Like the majority of the thigh adductors, adductor brevis is innervated by the obturator nerve. Obturator nerve is derived from the lumbar plexus (anterior branches of spinal nerves L2-L4).
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This question is part of the following fields:
- Anatomy
- Lower Limb
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Question 160
Incorrect
-
A 34-year-old male presents to the Emergency Department with the complaint of palpitations and difficulty breathing, which started suddenly half an hour ago. His ECG shows findings of supraventricular tachycardia. You attempt vagal manoeuvres but cannot convert them back to sinus rhythm. Therefore, drug therapy is necessary to terminate the arrhythmia. Adenosine cannot be used in this patient because of a contra-indication listed in his medical record. Which one of the conditions listed below would be a contraindication in this case?
Your Answer:
Correct Answer: Asthma
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.
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This question is part of the following fields:
- Cardiovascular Pharmacology
- Pharmacology
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Question 161
Incorrect
-
The tetanus vaccination contains inactivated tetanus toxoid, which induces the body to produce protective antibodies. How do these antibodies protect the body from tetanus?
Your Answer:
Correct Answer: Neutralise the protein exotoxin of C. tetani
Explanation:C. Tetanospasmin, an exotoxin produced by tetani, is responsible for the neurotoxic consequences of tetanus. The tetanus vaccination contains inactivated tetanus toxoid, which induces the body to produce protective antibodies that neutralize the tetanus toxin. It induces active immunization against Clostridium tetani exotoxin via toxoid-induced Ab generation.
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This question is part of the following fields:
- Microbiology
- Pathogens
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Question 162
Incorrect
-
Which of the following is NOT a typical feature of an abducens nerve palsy:
Your Answer:
Correct Answer: Inability to look up
Explanation:CN VI 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.
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This question is part of the following fields:
- Anatomy
- Cranial Nerve Lesions
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Question 163
Incorrect
-
Adrenocorticotropic hormone release from the anterior pituitary is stimulated by which of the following:
Your Answer:
Correct Answer: Corticotropin-releasing hormone
Explanation:ACTH secretion is stimulated by corticotropin-releasing hormone (CRH) from the hypothalamus.
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This question is part of the following fields:
- Endocrine
- Physiology
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Question 164
Incorrect
-
Most of the lymph from vessels that drain the breast is collected in which of the following lymph nodes?
Your Answer:
Correct Answer: Axillary nodes
Explanation:Lymph is the fluid that flows through the lymphatic system. Axillary lymph nodes are near the breasts. They are often the first location to which breast cancer spreads if it moves beyond the breast tissue. They receive approximately 75% of lymph drainage from the breast via lymphatic vessels, laterally and superiorly. The lymph usually first drains to the anterior axillary nodes, and from here, through the central axillary, apical, and supraclavicular nodes in sequence.
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This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 165
Incorrect
-
For an action potential to occur, which of the following must be true:
Your Answer:
Correct Answer: Depolarisation of the membrane must reach threshold potential
Explanation:For an action potential to occur, the membrane must become more permeable to Na+and the Na+influx must be greater than the K+efflux. An action potential occurs when depolarisation of the membrane reaches threshold potential. The membrane must be out of the absolute refractory period, however an action potential can still occur in a relative refractory period but only in response to a larger than normal stimulus.
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This question is part of the following fields:
- Basic Cellular
- Physiology
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Question 166
Incorrect
-
Which of these statements about the monospot test is true?
Your Answer:
Correct Answer: It can be positive in rubella
Explanation:Infectious mononucleosis can be diagnosed using specific EBV antibodies and a variety of unrelated non-EBV heterophile antibodies.Heterophile antibodies:About 70-90% of patients with EBV infectious mononucleosis produce antibodies against an antigen produced in one species that react against antigens from other species called heterophile antibodies. False positives can be seen with rubella, hepatitis, SLE, malaria, toxoplasmosis, lymphoma and leukaemia. These antibodies can be detected by two main screening tests:The monospot test uses horse red blood cells. It agglutinates in the presence of heterophile antibodies.Paul-Bunnell test uses sheep red blood cells. The blood agglutinates in the presence of heterophile antibodies.EBV-specific antibodies:Patients can remain heterophile-negative after six weeks and are then considered to be heterophile-negative and should be tested for EBV-specific antibodies. EBV-specific antibodies test are helpful if a false positive heterophile antibody test is suspected.The indirect Coombs test is used to detect in-vitro antibody-antigen reactions. It is typically used in antenatal antibody screening and in preparation for blood transfusion.Heterophile antibody tests are generally not positive in the incubation period of infectious mononucleosis (4-6 weeks) before the onset of symptoms.
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This question is part of the following fields:
- Microbiology
- Specific Pathogen Groups
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Question 167
Incorrect
-
A 25-year-old female arrives at the emergency room with a severe case of asthma. When she doesn't seem to be improving after initial treatment, you decide to start an aminophylline infusion.From the options below, which is Aminophylline's main mechanism of action?Â
Your Answer:
Correct Answer: Phosphodiesterase inhibition
Explanation:Theophylline and Ethylenediamine are combined in a 2:1 ratio to form Aminophylline. Its solubility is improved by the addition of Ethylenediamine. It has a lower potency and a shorter duration of action than Theophylline.It is used to treat the following conditions: Heart failureIt is used to treat the following conditions: COPDBradycardiasAminophylline has the following properties:Phosphodiesterase inhibitor that increases intracellular cAMP and relaxes smooth muscle in the bronchial airways and pulmonary blood vessels.Mast cell stabilization is achieved by using a non-selective adenosine receptor antagonist.It has slight positive inotropic and chronotropic effects, increasing cardiac output and decreasing systemic vascular resistance, lowering arterial blood pressure. It has been used historically in the treatment of refractory heart failure and is indicated by the current ALS guidelines as a substitute treatment for bradycardia. The daily oral dose for adults is 900 mg, divided into 2-3 doses. For severe asthma or COPD, a loading dosage of 5 mg/kg over 10-20 minutes is given, followed by a continuous infusion of 0.5 mg/kg/hour. The therapeutic range is small (10-20 microgram/ml), hence assessments of aminophylline plasma concentrations are useful during long-term treatment.
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This question is part of the following fields:
- Pharmacology
- Respiratory Pharmacology
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Question 168
Incorrect
-
A 75-year-old man with rheumatoid arthritis had gained weight, developed resistant hypertension, muscle weakness, and ankle oedema. This patient is most likely suffering from what condition?
Your Answer:
Correct Answer: Cushing's syndrome
Explanation:Overuse of cortisol medication, as seen in the treatment of patients with chronic asthma or rheumatoid arthritis, can cause Cushing’s syndrome. Weight gain, thin arms and legs, a round face, increased fat around the base of the neck, a fatty hump between the shoulders, easy bruising, wide purple stretch marks primarily on the abdomen, breasts, hips, and under the arms, weak muscles, hirsutism, hypertension, erectile dysfunction, osteoporosis, frontal alopecia, acne, depression, poor wound healing, and polycythaemia are all clinical features of Cushing’s syndrome.
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This question is part of the following fields:
- Endocrine
- Physiology
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Question 169
Incorrect
-
A 21-year-old student presents to the minors area of your Emergency Department with a laceration on his external nose that occurred during sparring in a kickboxing class. The area is bleeding profusely and will require suturing. Pressure is being applied. The laceration extends through some of the nasal muscles.Motor innervation of the nasal muscles of facial expression is provided by which of the following ? Select ONE answer only.
Your Answer:
Correct Answer: Facial nerve
Explanation:The facial nerve (the labyrinthine segment) is the seventh cranial nerve, or simply CN VII. It emerges from the pons of the brainstem, controls the muscles of facial expression, and functions in the conveyance of taste sensations from the anterior two-thirds of the tongue.Motor innervation of the nasal muscles of facial expression is provided by the facial nerve (CN VII).
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This question is part of the following fields:
- Anatomy
- Head And Neck
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Question 170
Incorrect
-
Identify the type of graph described below:This graph is a scatter plot of the effect estimates from individual studies against some measure of each study's size or precision.
Your Answer:
Correct Answer: Funnel plot
Explanation:A funnel plot is a scatter plot of the effect estimates from individual studies against some measure of each study’s size or precision. The standard error of the effect estimate is often chosen as the measure of study size and plotted on the vertical axis with a reversed scale that places the larger, most powerful studies towards the top. The effect estimates from smaller studies should scatter more widely at the bottom, with the spread narrowing among larger studies. In the absence of bias and between study heterogeneity, the scatter will be due to sampling variation alone and the plot will resemble a symmetrical inverted funnel. A triangle centred on a fixed effect summary estimate and extending 1.96 standard errors either side will include about 95% of studies if no bias is present and the fixed effect assumption (that the true treatment effect is the same in each study) is valid.
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This question is part of the following fields:
- Evidence Based Medicine
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Question 171
Incorrect
-
Which of the following clinical features is most suggestive of a lesion of the temporal lobe:
Your Answer:
Correct Answer: Receptive dysphasia
Explanation:Damage to the Wernicke’s speech area in the temporal lobe can result in a receptive dysphasia. Hemispatial neglect is most likely to occur in a lesion of the parietal lobe. Homonymous hemianopia is most likely to occur in a lesion of the occipital lobe. Expressive dysphasia is most likely to occur in a lesion of the Broca speech area in the frontal lobe. Conjugate eye deviation towards the side of the lesion is most likely to occur in a lesion of the frontal lobe.
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This question is part of the following fields:
- Anatomy
- Central Nervous System
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Question 172
Incorrect
-
A 52-year-old man develops pneumonia 3 days following an admission for investigation of chest pain. He has coarse left basal crackles and evidence of consolidation in the left lower lobe of chest X-ray. He has no known drug allergies.According to the latest NICE guidelines, which of the following antibacterial agents would be most appropriate to prescribe in this case? Select ONE answer only.
Your Answer:
Correct Answer: Co-amoxiclav
Explanation:Nosocomial infections are defined as those occurring within 48 hours of hospital admission, 3 days of discharge or 30 days of an operation. They affect 1 in 10 patients admitted to hospital. Annually, this results in 5000 deaths with a cost to the National Health Service of a billion pounds. On average, a patient with hospital acquired infection spent 2.5-times longer in hospital, incurring additional costs of £3000 more than an uninfected patient. Intensive care units (ICU) have the highest prevalence of hospital-acquired infections in the hospital setting.The current recommendations by NICE and the BNF on the treatment of hospital acquired pneumonia are:Early onset infection(less than 5 days after admission to hospital): co-amoxiclav or cefuroxime for 7 daysLate-onset infection(more than 5 days after admission to hospital): an antipseudomonal penicillin (e.g. piperacillin with tazobactam), a broad-spectrum cephalosporin (e.g. ceftazidime), or a quinolone (e.g. ciprofloxacin)If the patient developed a hospital-acquired pneumonia within 5 days of admission – co-amoxiclav would be the most appropriate choice.If the patient has developed a hospital-acquired pneumonia > 5 days after admission – ciprofloxacin would be the most appropriate choice from the list of options available.
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This question is part of the following fields:
- Microbiology
- Principles Of Microbiology
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Question 173
Incorrect
-
A 30-year old male is brought to the emergency room after a terrible fall during a photoshoot. The patient reported falling on his right forearm. There is evident swelling and tenderness on the affected area, with notable weakness of the flexor pollicis longus muscle. Radiographic imaging showed a fracture on the midshaft of the right radius.Which of the following nerves is most likely injured in the case above?
Your Answer:
Correct Answer: The anterior interosseous nerve
Explanation:Flexor pollicis longus receives nervous supply from the anterior interosseous branch of median nerve, derived from spinal roots C7 and C8.
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This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 174
Incorrect
-
The 'pump handle' movement of the thoracic wall describes which of the following movements:
Your Answer:
Correct Answer: The anterior ends of the ribs moving upwards and forwards
Explanation:Because the anterior ends of the ribs are inferior to the posterior ends, when the ribs are elevated, the anterior end moves upwards and forwards, moving the sternum upwards and forwards in turn. This ‘pump handle’ upwards and forwards movement changes the anteroposterior (AP) dimension of the thorax.
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This question is part of the following fields:
- Anatomy
- Thorax
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Question 175
Incorrect
-
The monospot test for infectious mononucleosis uses which of the following types of red blood cell?
Your Answer:
Correct Answer: Horse red blood cells
Explanation:Infectious mononucleosis can be diagnosed using specific EBV antibodies and a variety if unrelated non-EBV heterophile antibodies. These antibodies can be detected by two main screening tests:The monospot test uses horse red blood cells. It agglutinates in the presence of heterophile antibodies.Sheep red blood cells is used in Paul-Bunnell test. The blood agglutinates in the presence of heterophile antibodies.
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This question is part of the following fields:
- Microbiology
- Specific Pathogen Groups
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Question 176
Incorrect
-
Which of the following is NOT an adverse effect of amitriptyline:
Your Answer:
Correct Answer: Hypokalaemia
Explanation:Adverse effects include:Antimuscarinic effects: Dry mouth, Blurred vision, Constipation, Urinary retention, Sedation, ConfusionCardiovascular effects: Heart block, Arrhythmias, Tachycardia, Postural hypotension, QT-interval prolongation, Hepatic impairment, Narrow-angle glaucoma
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This question is part of the following fields:
- Central Nervous System
- Pharmacology
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Question 177
Incorrect
-
Surface area of the absorptive surface in the small intestine is increased by all but which of the following:
Your Answer:
Correct Answer: Teniae coli
Explanation:Factors increasing the surface area include:The small intestine is very long – about 5 m in length.The inner wall of the small intestine is covered by numerous folds of mucous membrane called plicae circulares.The lining of the small intestine is folded into many finger-like projections called villi.The surface of the villi is covered with a layer of epithelial cells which, in turn, have many small projections called microvilli that project towards the lumen of the intestine (forming the brush border).
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This question is part of the following fields:
- Gastrointestinal
- Physiology
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Question 178
Incorrect
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The results from the study investigating the accuracy of a new diagnostic test can be displayed in the following format. How is the negative predictive value calculated:Those with diseaseThose without diseaseTotalTest positiveaba+bTest negativecdc+dTotala+cb+dn=a+b+c+d
Your Answer:
Correct Answer: d/(c+d)
Explanation:Negative predictive value (NPV) is the proportion of individuals with a negative test result who do not have the disease.NPV = d/(c+d)
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This question is part of the following fields:
- Evidence Based Medicine
- Statistics
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Question 179
Incorrect
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When a person changes from a supine to an upright position, which of the followingcompensatory mechanismsoccurs:
Your Answer:
Correct Answer: Increased contractility
Explanation:On standing from a prone position, gravity causes blood to pool in veins in the legs. Central venous pressure (CVP) falls, causing a fall in stroke volume and cardiac output (due to Starling’s law) and thus a fall in blood pressure. Normally this fall in BP is rapidly corrected by the baroreceptor reflex which causes venoconstriction (partially restoring CVP), and an increase in heart rate and contractility, so restoring cardiac output and blood pressure. Impaired autonomic nervous activity in the elderly accounts for the greater likelihood of postural hypotension. Any symptoms of dizziness, blurred vision or syncope is due to a transient fall in cerebral perfusion that occurs before cardiac output and mean arterial pressure (MAP) can be corrected.
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This question is part of the following fields:
- Cardiovascular
- Physiology
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Question 180
Incorrect
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A 72-year-old man presents with chest pain that is characteristic of angina. You administer a dose of glyceryl trinitrate (GTN), which rapidly resolved his symptoms. Unfortunately, he also develops an unpleasant side effect.Which of the following side effects is he most likely to have developed? Select ONE answer only.
Your Answer:
Correct Answer: Headache
Explanation:Nitrates are used in the treatment of angina pectoris and the prevention of myocardial ischaemia. Commonly used examples of nitrates are glyceryl trinitrate and isosorbide dinitrate. Unwanted effects, however, are common and can limit therapy, particularly when angina is severe or when patients are unusually sensitive to the effects of nitrates.The following are common or very common side effects of nitratesArrhythmiasAstheniaCerebral ischaemiaDizzinessDrowsinessFlushingHeadacheHypotensionNausea and vomitingDiarrhoea, syncope and cyanosis can occur, but these are rare side effects. Dry eyes, bradycardia and metabolic acidosis have not been reported.
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This question is part of the following fields:
- Cardiovascular Pharmacology
- Pharmacology
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SESSION STATS - PERFORMANCE PER SPECIALTY
