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Question 1
Incorrect
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A 29-year-old male patient with a history of three previous chest infections in the past seven months presents with fever, pleuritic pain and productive cough. Chest x-ray shows lobar consolidation and the diagnosis of a fourth chest infection is established, after sputum culture reveals Haemophilus influenzae. The previous chest infections were due to Streptococcus pneumoniae. After a period of six weeks, a full blood count, urea, CRP, electrolytes and chest x-ray turn out as normal. What is the investigation you would choose next?
Your Answer: HIV test
Correct Answer: Serum immunoglobulins
Explanation:Hypogammaglobulinemia occurs due to a variety of underlying primary or secondary immunodeficient states, including HIV which is suspected in this case. The most commonly recognised clinical feature is recurrent infection.
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This question is part of the following fields:
- Clinical Sciences
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Question 2
Correct
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Which one of the following conditions is least likely to be associated with pyoderma gangrenosum?
Your Answer: Syphilis
Explanation:The following are conditions commonly associated with pyoderma gangrenosum:
Inflammatory bowel disease:
– Ulcerative colitis
– Crohn’s disease
Arthritides:
– Rheumatoid arthritis
– Seronegative arthritis
Haematological disease:
– Myelocytic leukaemia[8]
– Hairy cell leukaemia
– Myelofibrosis
– Myeloid metaplasia
– Monoclonal gammopathy
Autoinflammatory disease:
– Pyogenic sterile arthritis, pyoderma gangrenosum, and acne syndrome (PAPA syndrome)
– Granulomatosis with polyangiitis -
This question is part of the following fields:
- Dermatology
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Question 3
Incorrect
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Choose the hormone secreted only by the adrenal medulla:
Your Answer: Cortisol
Correct Answer: Adrenaline
Explanation:The major endocrine functions of adrenal gland are to produce catecholamines and steroids. Catecholamine, synthesized by the adrenal medulla, is responsible for blood pressure and blood flow regulation whereas steroids produced by the cortex control energy and water homeostasis and immune responses. Glucocorticoids, a major group of adrenal steroids, have a stimulatory effect on catecholamine synthesis in the medulla.
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This question is part of the following fields:
- Clinical Sciences
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Question 4
Incorrect
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What are the most common types of transformation seen in patients with polycythaemia vera?
Your Answer: Myelodysplasia + myelofibrosis
Correct Answer: Myelofibrosis + acute myeloid leukaemia
Explanation:5–15% of the cases of polycythaemia vera progress to myelofibrosis or acute myeloid leukaemia (AML).
Polycythaemia vera (PV), also known as polycythaemia rubra vera, is a myeloproliferative disorder caused by clonal proliferation of marrow stem cells leading to an increase in red cell volume, often accompanied by overproduction of neutrophils and platelets. It has peak incidence in the sixth decade of life, with typical features including hyperviscosity, pruritus, splenomegaly, haemorrhage (secondary to abnormal platelet function), and plethoric appearance.
Some management options of PV include lose-dose aspirin, venesection (first-line treatment), hydroxyurea (slightly increased risk of secondary leukaemia), and radioactive phosphorus (P-32) therapy.
In PV, thrombotic events are a significant cause of morbidity and mortality. 5–15% of the cases progress to myelofibrosis or AML. The risk of having AML is increased with chemotherapy treatment.
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This question is part of the following fields:
- Haematology & Oncology
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Question 5
Incorrect
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A 19-year-old woman is diagnosed with acute purulent meningitis after returning from a recent holiday abroad. Which of the following investigations is the least relevant?
Your Answer: Streptococcal antigen testing
Correct Answer: PCR of CSF for Mycobacterium TB
Explanation:Amoebic, bacterial and fungal meningitis may present acutely but is not common in tuberculous meningitis. Amoebic meningitis is caused by Naegleria fowleri as a result of swimming in infected freshwater. The organism may be found in fresh CSF specimens with phase contrast microscopy.
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This question is part of the following fields:
- Infectious Diseases
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Question 6
Incorrect
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An 80 year old female, previously diagnosed with polymyalgia rheumatica 18 months back, presents to the outpatient clinic with bilateral shoulder stiffness and generalized myalgia. The ESR was found to be 60mm/1st hour at the time of presentation. Prednisolone therapy was initiated at a daily dose of 15 mg along with Calcium and Vitamin supplementation. She reported resolution of her symptoms in one week. However the symptoms relapsed when the prednisolone dose was reduced below the current dose of 12.5 mg daily. How should she be ideally managed?
Your Answer: Increase the dose of prednisolone and add a bisphosphonate
Correct Answer: Continue the current dose of prednisolone and start methotrexate
Explanation:Polymyalgia rheumatica, a syndrome characterized by proximal muscle pain and stiffness in older persons, generally is treated with prednisone. Dosages of 15 to 25 mg of prednisone per day can reduce inflammation considerably, although many patients relapse when therapy is tapered. Long-term (18 to 36 months) steroid treatment has been recommended by several studies, but this can result in multiple side effects, including osteoporosis, hypertension, cataracts, and hyperglycaemia. Methotrexate has been used to reduce inflammation in rheumatoid arthritis, systemic vasculitis, and giant cell arteritis, and in some studies has been combined with prednisone to treat polymyalgia rheumatica, decreasing the duration of treatment.
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This question is part of the following fields:
- Rheumatology
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Question 7
Correct
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A 60 yr. old patient with hypertension attended his regular clinic. His compliance was poor. His blood pressure was 180/100 mmHg. His pulse rate was 85 bpm which was irregularly irregular. On examination there was bibasal crepitation. No murmurs were heard. What is the most likely cause for these findings?
Your Answer: Left ventricular hypertrophy
Explanation:Left ventricular hypertrophy due to long standing hypertension is the most probable cause. The irregularly irregular pulse was suggestive of atrial fibrillation, which is due to diastolic dysfunction. Poor ventricular filling causes pulmonary congestion which manifests as bibasal crepitations.
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This question is part of the following fields:
- Cardiology
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Question 8
Correct
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A 28-year-old woman is evaluated in the endocrinology clinic for increased urine output. She weighs 60 kg and has a 24-hour urine output of 3500 ml. Her basal urine osmolality is 210 mOsm/kg. She undergoes a fluid deprivation test and her urine osmolality after fluid deprivation (loss of weight 3 kg) is 650 mOsm/kg. Subsequent injection of subcutaneous DDAVP (desmopressin acetate) did not result in a further significant rise of urine osmolality after 2 hours (655 mOsm/kg). Which of the following is the most likely diagnosis?
Your Answer: Primary polydipsia
Explanation:In central and nephrogenic diabetes insipidus (DI), urinary osmolality will be less than 300 mOsm/kg after water deprivation. After the administration of ADH, the osmolality will rise to more than 750 mOsm/kg in central DI but will not rise at all in nephrogenic DI.
In primary polydipsia, water deprivation results in an increase in urine osmolality, anywhere between 300 – 800 mOsm/Kg (usually up to 600 – 700 mOsm/Kg), without a substantial increase in plasma osmolality, but the increase in urine osmolality is not as substantial as in a normal response.
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This question is part of the following fields:
- Endocrinology
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Question 9
Incorrect
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The chorda tympani of the facial nerve (CN VII) carries:
Your Answer: parasympathetic fibres to the submandibular and sublingual glands and the nerve to stapedius
Correct Answer: parasympathetic fibres to the submandibular and sublingual glands and taste fibres from the anterior two-thirds of the tongue
Explanation:In the petrous temporal bone the facial nerve produces three branches:
1. The greater petrosal nerve, which transmits preganglionic parasympathetic fibres to the sphenopalatine ganglion. These postganglionic fibres supply the lacrimal gland and the glands in the nasal cavity;
2. The nerve to stapedius;
3. Parasympathetic fibres to the submandibular and sublingual glands and taste fibres from the anterior two-thirds of the tongue. -
This question is part of the following fields:
- Neurology
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Question 10
Correct
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Hepatitis C is what kind of virus?
Your Answer: A variable RNA virus
Explanation:Hepatitis C is a single-stranded positive sense RNA virus. It is variable because of the high rate of error of RNA-dependent RNA polymerase and the pressure from the host immune system has caused HCV to evolve and develop seven genetic lineages.
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This question is part of the following fields:
- Gastroenterology
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Question 11
Correct
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A 20-year-old man presents with an acute exacerbation of asthma associated with a chest infection. He is unable to complete a sentence and his peak flow rate was 34% of his normal level. He is treated with high-flow oxygen, nebulised bronchodilators, and oral corticosteroids for three days, but his condition has not improved. Which of the following intravenous treatments would be the best option for this patient?
Your Answer: Magnesium
Explanation:A single dose of intravenous magnesium sulphate is safe and may improve lung function and reduce intubation rates in patients with acute severe asthma. Intravenous magnesium sulphate may also reduce hospital admissions in adults with acute asthma who have had little or no response to standard treatment.
Consider giving a single dose of intravenous magnesium sulphate to patients with acute severe asthma (PEF <50% best or predicted) who have not had a good initial response to inhaled bronchodilator therapy. Magnesium sulphate (1.2–2 g IV infusion over 20 minutes) should only be used following consultation with senior medical staff.
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This question is part of the following fields:
- Respiratory
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Question 12
Correct
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A cohort study is developed to assess the correlation between blood pressure and working long hours. After 10 years of follow-up and for the 1050 individuals working less than 40 hours per week, 1000 patients had normal blood pressure and 50 patients were diagnosed with hypertension. For the 660 patients working more than 40 hours per week, 600 patients had normal blood pressure and 60 patients were diagnosed with hypertension. If you work more than 40 hours per week, what is the odds ratio of developing hypertension compared to the individuals working less than 40 hours per week?
Your Answer: 2
Explanation:An odds ratio (OR) is a measure of the association between an exposure and an outcome. The OR represents the odds that an outcome will occur given a particular exposure, compared to the odds of the outcome occurring in the absence of that exposure. Odds ratios are most commonly used in case-control studies, however they can also be used in cross-sectional and cohort study designs as well (with some modifications and/or assumptions). Where
a = Number of exposed cases
b = Number of exposed non-cases
c = Number of unexposed cases
d = Number of unexposed non-cases
OR=(a/c) / (b/d) = ad/bc
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This question is part of the following fields:
- Clinical Sciences
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Question 13
Incorrect
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In a patient with prostate cancer, what is the mechanism by which goserelin acts?
Your Answer: Androgen receptor antagonist
Correct Answer: GnRH agonist
Explanation:Androgen deprivation therapy (ADT) for prostate cancer:
Goserelin (Zoladex) is a synthetic gonadotropin-releasing hormone (GnRH) analogue; chronic stimulation of goserelin results in suppression of LH, FSH serum levels thereby preventing a rise in testosterone.
Dosage form: 3.6 mg/10.8mg implants.
Adverse effects include flushing, sweating, diarrhoea, erectile dysfunction, less commonly, rash, depression, hypersensitivity, etc.
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This question is part of the following fields:
- Pharmacology
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Question 14
Incorrect
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A 22-year-old woman presents with anxiety and weight loss with increased appetite. Thyrotoxicosis is suspected and various investigations are performed. Which of the following findings is most consistent with Graves’ disease?
Your Answer: Low thyroid uptake of technecium-99m
Correct Answer: High titre of thyroid peroxidase autoantibodies
Explanation:Free T4 levels or the free T4 index is usually elevated, as is the free T3 level or free T3 index
– Assays for thyrotropin-receptor antibodies (particularly TSIs) almost always are positive.
– Detection of TSIs is diagnostic for Graves disease.
– Other markers of thyroid autoimmunity, such as antithyroglobulin antibodies or antithyroid peroxidase antibodies, are usually present.
– Other autoantibodies that may be present include thyrotropin receptor-blocking antibodies and anti–sodium-iodide symporter antibody.
The presence of these antibodies supports the diagnosis of autoimmune thyroid disease.
– The radioactive iodine uptake is increased and the uptake is diffusely distributed over the entire gland. -
This question is part of the following fields:
- Endocrinology
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Question 15
Correct
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A 63-year-old woman visits the diabetes clinic for review. She has had type-2 diabetes for 9 years and is now on insulin therapy. She has diabetic nephropathy, as exemplified by hypertension and proteinuria (urinary PCR 155); a recent creatinine level was 205 μmol/l and eGFR 24 ml/min. Which of the following options best fits her prognosis or management?
Your Answer: Treatment with ARB or ACE-I may slow further deterioration in renal function
Explanation:Treatment with ARB or ACE-I may slow further deterioration in renal function in this patient, as studies have shown that blocking of the RAS in type 2 diabetic patients improve renal function.
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This question is part of the following fields:
- Nephrology
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Question 16
Correct
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Choose the correct statement regarding standard polymerase chain reaction:
Your Answer: A thermostable DNA polymerase is required
Explanation:In the PCR, DNA amplification is performed by thermostable enzymes; invariably either family A DNA polymerases from thermophilic and hyperthermophilic Bacteria or family B DNA polymerases from hyperthermophilic Archaea. Family Y DNA polymerase from the hyperthermophilic archaeon Sulfolobus solfataricus, Sso-polY, is also an enzyme marketed for PCR, but with specialist applications. Each thermostable DNA polymerases has different characteristics and to achieve optimal results, the choice of a PCR enzyme depends on the application itself.
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This question is part of the following fields:
- Clinical Sciences
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Question 17
Incorrect
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A 25-year-old man asks to be referred to a plastic surgeon as he claims that his ears are too big in proportion to his face and he seldom leaves the house because of this. His records show that he was treated for anxiety and depression with fluoxetine previously and has been off work with back pain for the past 4 months. On examination, his ears appear to be normal. What is the most appropriate term of this behaviour?
Your Answer: Hypochondriasis
Correct Answer: Dysmorphophobia
Explanation:The most probable diagnosis in the given scenario would be body dysmorphic disorder or dysmorphophobia
It is a mental disorder where patients have a significantly distorted body image.
Diagnostic and Statistical Manual (DSM) IV criteria:
Preoccupation with an imagined defect in appearance. If a slight physical anomaly is present, the person’s concern is markedly excessive.
The preoccupation causes clinically significant distress or impairment in social, occupational, or other important areas of functioning
The preoccupation is not better accounted for by another mental disorder (e.g., dissatisfaction with body shape and size in Anorexia Nervosa).Treatment:
Cognitive-behavioural therapy (CBT) is the most commonly used and most empirically supported intervention to improve body image.
Several drugs have been targets of study in anorexia nervosa treatment, including selective serotonin reuptake inhibitors, antidepressants, antipsychotics, nutritional supplementation, and hormonal medications. -
This question is part of the following fields:
- Psychiatry
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Question 18
Incorrect
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A 24-year-old male is admitted with worsening shortness of breath with signs of left ventricular failure. He has a known genetic condition. On examination, there is an ejection systolic murmur loudest over the aortic area radiating to the carotids, bibasal crepitations and pitting oedema to the knees bilaterally. On closer inspection of the patient, you note a wide vermillion border, small spaced teeth and a flat nasal bridge. The patient also has a disinhibited friendly demeanour. What is the likely precipitating valvular issue?
Your Answer: Aortic regurgitation
Correct Answer: Supravalvular aortic stenosis
Explanation:Supravalvular aortic stenosis, is associated with a condition called William’s syndrome.
William’s syndrome is an inherited neurodevelopmental disorder caused by a microdeletion on chromosome 7. The most common symptoms of Williams syndrome are heart defects and unusual facial features. Other symptoms include failure to gain weight appropriately in infancy (failure to thrive) and low muscle tone. Individuals with Williams syndrome tend to have widely spaced teeth, a long philtrum, and a flattened nasal bridge.
Most individuals with Williams syndrome are highly verbal relative to their IQ, and are overly sociable, having what has been described as a cocktail party type personality. -
This question is part of the following fields:
- Clinical Sciences
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Question 19
Incorrect
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A 44-year-old hairdresser with a history of myasthenia gravis is admitted to the Emergency Department. She is currently taking pyridostigmine, but there has been a significant worsening of her symptoms following antibiotic treatment for a chest infection. On examination she is dyspnoeic and cyanotic with quiet breath sounds in both lungs. Other than respiratory support, what are the two other treatments of choice?
Your Answer: IV methylprednisolone or plasmapheresis
Correct Answer: Plasmapheresis or intravenous immunoglobulins
Explanation:This patient is having a myasthenic crisis. Opinions vary as to whether plasmapheresis or intravenous immunoglobulins should be given first-line. Plasmapheresis usually works much faster, but is more costly due to equipment.
Myasthenia gravis is an autoimmune disorder resulting in insufficient functioning acetylcholine receptors. Antibodies to acetylcholine receptors are seen in 85-90% of cases. Myasthenia gravis is more common in women (2:1). -
This question is part of the following fields:
- Neurology
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Question 20
Incorrect
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A 60 year old man who has been complaining of increasing shortness of breath had a post-bronchodilator spirometry done. FEV1/FVC 0. 63 FEV1% predicted 63% What is the best interpretation of these results?
Your Answer: Asthma
Correct Answer: COPD (stage 2 - moderate)
Explanation:Chronic obstructive pulmonary disease (COPD) is a complex and progressive chronic lung disease. Typically, COPD includes emphysema and chronic bronchitis. COPD is characterized by the restriction of airflow into and out of the lungs. The obstruction of airflow makes breathing difficult. The causes of COPD include smoking, long-term exposure to air pollutants and a rare genetic disorder.
The Global Initiative for Chronic Obstructive Lung Disease (GOLD) developed the GOLD Staging System. In the GOLD System, the forced expiratory volume in one second (FEV1) measurement from a pulmonary function test is used to place COPD into stages. Often, doctors also consider your COPD symptoms.
COPD has four stages. The stages of COPD range from mild to very severe. COPD affects everyone differently. Because COPD is a progressive lung disease, it will worsen over time.
The Stages of COPD:
Mild COPD or Stage 1—Mild COPD with a FEV1 about 80 percent or more of normal.
Moderate COPD or Stage 2—Moderate COPD with a FEV1 between 50 and 80 percent of normal.
Severe COPD or Stage 3—Severe emphysema with a FEV1 between 30 and 50 percent of normal.
Very Severe COPD or Stage 4—Very severe or End-Stage COPD with a lower FEV1 than Stage 3, or people with low blood oxygen levels and a Stage 3 FEV1.This patient has a FEV1 percent of 63 which falls within the stage 2 or moderate COPD.
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This question is part of the following fields:
- Respiratory
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Question 21
Correct
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A 24-year-old man was hit on the lateral aspect of his head by a high velocity cricket ball and lost consciousness immediately. Paramedics found him to have a Glasgow coma score of 15 but take him to the A&E for further investigation. His Glasgow coma score on examination in the A&E is 13 (M5, V4, E4) and he has anterograde and retrograde amnesia to recent events. The doctors arrange an urgent CT scan. Which clinical sign would be most concerning if present?
Your Answer: Bradycardia
Explanation:Intracranial pressure (ICP) is a complex brain modality that determines cerebral perfusion pressure (CPP), which is the difference between arterial blood pressure (ABP), and ICP. Raised ICP reduces CPP and blood delivery to the brain. This jeopardizes cerebral function and organismal survival in many species. A massive rise in ICP is also known to produce an increase in ABP, bradycardia and respiratory irregularities termed Cushing response. This mechanism is generally considered to be an agonal and terminal event occurring in extreme condition of brainstem ischaemia leading to a sympatho-adrenal response.
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This question is part of the following fields:
- Clinical Sciences
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Question 22
Incorrect
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A woman with severe renal failure undergoes a kidney transplant. However, after a few hours, she develops fever and anuria. The doctors are suspecting hyperacute organ rejection. Which are the cells primarily responsible for hyperacute organ rejection?
Your Answer: Helper T Cells
Correct Answer: B Cells
Explanation:Hyperacute rejection appears in the first minutes following transplantation and occurs only in vascularized grafts. This very fast rejection is characterized by vessel thrombosis leading to graft necrosis. Hyperacute rejection is caused by the presence of antidonor antibodies existing in the recipient before transplantation. These antibodies induce both complement activation and stimulation of endothelial cells to secrete Von Willebrand procoagulant factor, resulting in platelet adhesion and aggregation. The result of these series of reactions is the generation of intravascular thrombosis leading to lesion formation and ultimately to graft loss. Today, this type of rejection is avoided in most cases by checking for ABO compatibility and by excluding the presence of antidonor human leukocyte antigen (HLA) antibodies by cross-match techniques between donor graft cells and recipient sera. This type of rejection is also observed in models of xenotransplantation of vascularized organs between phylogenetically distant species when no immunosuppressive treatment is given to the recipients.
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This question is part of the following fields:
- Clinical Sciences
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Question 23
Correct
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A 65 yr. old male presented with acute ST elevation myocardial infarction and thrombolysis was planned. Which of the following is an absolute contraindication for thrombolysis?
Your Answer: Intracerebral Haemorrhage
Explanation:Absolute contraindications for fibrinolytic use in STEMI
Prior intracranial haemorrhage (ICH)
Known structural cerebral vascular lesion
Known malignant intracranial neoplasm
Ischemic stroke within 3 months
Suspected aortic dissection
Active bleeding or bleeding diathesis (excluding menses)
Significant closed head trauma or facial trauma within 3 months
Intracranial or intraspinal surgery within 2 months
Severe uncontrolled hypertension (unresponsive to emergency therapy)
For streptokinase, prior treatment within the previous 6 months -
This question is part of the following fields:
- Cardiology
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Question 24
Correct
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A 52-year-old woman is diagnosed as having acute myeloid leukaemia. What is the single most important test in determining her prognosis?
Your Answer: Cytogenetics
Explanation:All of the aforementioned options may be important however cytogenetics, for detecting chromosomal abnormalities, is the single most important test to determine her disease prognosis.
Acute myeloid leukaemia (AML) is the acute expansion of the myeloid stem line, which may occur as a primary disease or follow the secondary transformation of a myeloproliferative disorder. It is more common over the age of 45 and is characterized by signs and symptoms largely related to bone marrow failure such as anaemia (pallor, lethargy), frequent infections due to neutropenia (although the total leucocyte count may be very high), thrombocytopaenia (bleeding), ostealgia, and splenomegaly.
The disease has a poor prognosis if:
1. Age of the patient >60 years
2. >20% blasts seen after the first course of chemotherapy
3. Chromosomal aberration with deletion of part of chromosome 5 or 7.Acute promyelocytic leukaemia (APL) is an aggressive form of AML.
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This question is part of the following fields:
- Haematology & Oncology
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Question 25
Correct
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Which of the following parameters is increased as a result of asthma?
Your Answer: Residual volume
Explanation:In asthma, a reversible increase in residual volume (RV), functional residual capacity (FRC), and total lung capacity (TLC) may occur. There is a fall in FEV1, FVC and gas transfer.
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This question is part of the following fields:
- Respiratory
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Question 26
Correct
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A 48-year-old hairdresser presents to the GP with loss of sensation over the lateral three and a half fingers of her right hand, tenderness over her right forearm, and inability to make a tight fist. She complains of pain in her right arm when twisting door handles anticlockwise. Phalen’s and Tinel’s tests are negative. She is otherwise neurologically intact. Which of the following is the most likely diagnosis?
Your Answer: Pronator teres syndrome
Explanation:Entrapment of the median nerve by pronator teres causes a median nerve neuropathy, which is worse during pronation of the forearm. Examination should involve excluding carpal tunnel syndrome and pronation of the affected forearm against resistance, which brings on the pain. Unlike carpal tunnel syndrome, the median nerve proximal to the wrist may be tender to palpation.
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This question is part of the following fields:
- Neurology
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Question 27
Incorrect
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Regarding Giardia Lamblia which one of the following statements is true?
Your Answer: Often causes a bloody diarrhoea
Correct Answer: May cause intestinal malabsorption
Explanation:Giardiasis also known as travellers diarrhoea is caused by Giardia lamblia, which is an anaerobic parasite affecting the small intestine. It can lead to diarrhoea, flatulence, abdominal cramps, malodourous greasy stools and intestinal malabsorption. It can also cause bloody diarrhoea. The investigation of choice is stool examination for trophozoites and cysts. It is treated by metronidazole and tinidazole as first line therapies.
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This question is part of the following fields:
- Infectious Diseases
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Question 28
Correct
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A study is done on 1000 patients to assess the specificity of a new rapid finger-prick blood test developed to help diagnose deep vein thrombosis (DVT). The new test was positive on 200 patients with DVT and on 100 patients without DVT. It was also negative on 20 patients with DVT and 680 without DVT. What is the specificity of the new test?
Your Answer: 680/780
Explanation:Specificity (negative in health)
The ability of a test to correctly classify an individual as disease- free is called the test′s specificity. [Table 2]Specificity = d / b+d
= d (true negative) / b+d (true negative + false positive)
= Probability of being test negative when disease absent.
Example: One hundred persons with normal angles (diagnosed by ′gold standard′: gonioscopy) are examined by peripheral angle chamber depth examination. Eighty-five persons had normal peripheral angle chamber depth [Table 3]. The specificity of the peripheral angle chamber depth examination to PACG is therefore –
85 / 100 = 85%.
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This question is part of the following fields:
- Clinical Sciences
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Question 29
Incorrect
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A 64 year old woman who is of Asian descent and is diabetic (controlled by diet) presents with generalized body aches and difficulty rising from sitting for the last few months. Her blood glucose levels are in the normal range. Lab examination reveals normal blood cell count, low serum phosphate, calcium at the lower range, and raised alkaline phosphatase levels. Radiological examination shows which of the following?
Your Answer: Osteolytic areas with bone destruction
Correct Answer: Linear areas of low density
Explanation:Osteomalacia is a condition due to defective mineralization of osteoid. Occurs as a result of Vitamin D deficiency secondary to poor dietary intake and sun exposure, malabsorption e.g., inflammatory bowel disease and gastrointestinal bypass surgery. Radiological findings include reduced bone mineral density (a non specific finding), inability to radiologically distinguish vertebral body trabeculae (the film appears poor quality), looser pseudo fractures, fissures, or narrow radiolucent lines (these are the characteristic findings). Osteolytic or punched out lesions may be seen with multiple myeloma and bony metastases. Areas of sclerosis may be observed with conditions like osteosclerosis and Paget disease. A Brodie abscess is a subacute osteomyelitis, which may persist for years before progressing to a chronic, frank osteomyelitis.
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This question is part of the following fields:
- Rheumatology
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Question 30
Incorrect
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A 60-year-old woman presents to the oncology clinic with a general feeling of being unwell and temperature of 38.1°C. She is a known case of neuroendocrine cancer of the cervix, treated with carboplatin and etoposide. Her last treatment was eight days ago. Blood cultures are taken and she is started on neutropenic sepsis protocol. What will gram-staining of the blood cultures most likely show?
Your Answer: Gram-negative rods
Correct Answer: Gram-positive cocci
Explanation:Gram-staining of the blood cultures of this patient will show gram-positive cocci. Gram-negative bacilli used to be the most common pathogen isolated in neutropenic sepsis, but currently, the most common pathogens are gram-positive organisms. Staphylococcus epidermidis is the most frequent causative agent, and following this are other staphylococci and streptococci species.
Neutropenic sepsis is a relatively common complication of cancer therapy—usually chemotherapy. It most commonly occurs 7-14 days after the treatment and is usually defined as a neutrophil count of <0.5 x 10^9/L in a patient undergoing anticancer treatment and who has either a temperature higher than 38°C or has other features consistent with clinically significant sepsis. Management approach includes starting empirical antibiotic therapy (piperacillin with tazobactam—Tazocin) immediately. Following this initial treatment, the patient is usually assessed by a specialist and risk-stratified to see if outpatient treatment may be possible. However, if the patient remains febrile and unwell after 48 hours, an alternative antibiotic such as meropenem is often prescribed with or without vancomycin. If patient is still not responding after 4-6 days, then an antifungal, such as amphotericin B, is started after carrying out investigations (e.g. HRCT and Aspergillus PCR) to determine the likelihood of systemic fungal infection.
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This question is part of the following fields:
- Haematology & Oncology
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