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Question 1
Incorrect
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A man presents to the emergency department with a hand laceration that has damaged the opponens digiti minimi muscle.All of the following statements regarding the opponens digiti minimi muscle is considered correct, except:
Your Answer: It draws the fifth metacarpal bone anteriorly and rotates it
Correct Answer: It is innervated by the superficial branch of the ulnar nerve
Explanation:Opponens digiti minimi (ODM) is an intrinsic muscle of the hand. It’s a triangular muscle that extends between the hamate bone (carpal bone) and the 5th metacarpal bone. It forms the hypothenar muscle group together with the abductor digiti minimi and flexor digiti minimi brevis, based on the medial side of the palm (hypothenar eminence). These muscles act together in moving the little finger. The opponens digiti minimi is responsible for flexion, lateral rotation and opposition of the little finger.Its origin is the hook of hamate and flexor retinaculum. It inserts into the medial border of 5th metacarpal bone. It is innervated by the deep branch of the ulnar nerve, which stems from the brachial plexus (C8, T1 spinal nerves).Its blood supply is by the deep palmar branch of ulnar artery and deep palmar arch, which is the terminal branch of the radial artery.
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This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 2
Incorrect
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Which of the following microbes adheres to the genital mucosa using fimbriae:
Your Answer: Treponema pallidum
Correct Answer: Neisseria gonorrhoeae
Explanation:Infection of the genital mucosa by Neisseria gonorrhoeae involves attachment to and invasion of epithelial cells. Initial adherence of gonococci to columnar epithelial cells is mediated by type IV pili assembled from pilin subunit PilE proteins and pilus tip-associated PilC proteins, it then invades the epithelial layer, triggering a local acute inflammatory response.
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This question is part of the following fields:
- Microbiology
- Principles
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Question 3
Incorrect
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Which of the following hormones is dysfunctional in diabetes insipidus:
Your Answer: Insulin
Correct Answer: Antidiuretic hormone
Explanation:Diabetes insipidus (DI) may result from a deficiency of ADH secretion (cranial DI) or from an inappropriate renal response to ADH (nephrogenic DI). As a result, fluid reabsorption at the kidneys is impaired, resulting in large amounts of hypotonic, dilute urine being passed with a profound unquenchable polydipsia.The biochemical hallmarks of DI are:High plasma osmolality (> 295 mOsm/kg)Low urine osmolality (< 300 mOsm/kg)Hypernatraemia (> 145 mmol/L)High urine volume
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This question is part of the following fields:
- Endocrine
- Physiology
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Question 4
Incorrect
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During bedside rounds, an 82-year old female in the Medicine Ward complains of pain and tingling of all fingers of the right hand. The attending physician is considering carpal tunnel syndrome.Which of the following is expected to undergo atrophy in carpal tunnel syndrome?
Your Answer: The hypothenar eminence
Correct Answer: The thenar eminence
Explanation:Carpal tunnel syndrome (CTS) is an entrapment neuropathy caused by compression of the median nerve as it travels through the wrist’s carpal tunnel. It is the most common nerve entrapment neuropathy, accounting for 90% of all neuropathies. Early symptoms of carpal tunnel syndrome include pain, numbness, and paraesthesia’s. These symptoms typically present, with some variability, in the thumb, index finger, middle finger, and the radial half (thumb side) of the ring finger. Pain also can radiate up the affected arm. With further progression, hand weakness, decreased fine motor coordination, clumsiness, and thenar atrophy can occur.The muscles innervated by the median nerve can be remembered using the mnemonic ‘LOAF’:L– lateral two lumbricalsO– Opponens pollicisA– Abductor pollicisF– Flexor pollicis brevisIn the early presentation of the disease, symptoms most often present at night when lying down and are relieved during the day. With further progression of the disease, symptoms will also be present during the day, especially with certain repetitive activities, such as when drawing, typing, or playing video games. In more advanced disease, symptoms can be constant.Typical occupations of patients with carpal tunnel syndrome include those who use computers for extended periods of time, those who use equipment that has vibration such as construction workers, and any other occupation requiring frequent, repetitive movement.
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This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 5
Correct
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In a 7-year-old child with chickenpox, which of the following would you advise the mother NOT to do?
Your Answer: Give ibuprofen for the fever
Explanation:Chickenpox (varicella zoster) is a highly contagious airborne disease and has an incubation period of between 7-21 days. It often has a prodromal phase when there is a fever, aches and headaches, dry cough, and sore throat before onset of rash.Some recognized complications of chickenpox are:OrchitisHepatitisPneumoniaEncephalitisInfected spotsOtitis mediaMyocarditisGlomerulonephritisAppendicitisPancreatitisTreatment is symptomatic and includes using paracetamol to manage fever. There is a link between use of ibuprofen in patients with chicken-pox and necrotizing fasciitis so Ibuprofen should NOT be used. An emollient and antihistamine can be used to ease the itchy rash and oral hydration is encouraged.
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This question is part of the following fields:
- Microbiology
- Specific Pathogen Groups
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Question 6
Incorrect
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Regarding bias, which of the following statements is CORRECT:
Your Answer: Increasing the sample size reduces bias.
Correct Answer: Bias leads to the systematic difference between the results from a study and the true states of affair.
Explanation:Bias is the term used to describe an error at any stage of the study that was not due to chance. Bias leads to the systematic difference between the results from a study and the true states of affair. Bias may be introduced at all stages of the research process, from study design, through to analysis and publication. Bias can create a spurious association or mask a real association.Good research design can reduce the effect of bias (e.g. blinding, randomisation) but they cannot eliminate it completely. Increasing the sample size does not reduce bias.
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This question is part of the following fields:
- Evidence Based Medicine
- Study Methodology
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Question 7
Incorrect
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Which of the following clinical features would you NOT expect to see in a tibial nerve palsy:
Your Answer: Loss of plantarflexion of the foot
Correct Answer: Weakened eversion of the foot
Explanation:Damage to the tibial nerve results in loss of plantarflexion of the ankle and weakness of inversion of the foot resulting in a shuffling gait, clawing of the toes and loss of sensation in its cutaneous distribution.
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This question is part of the following fields:
- Anatomy
- Lower Limb
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Question 8
Correct
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Which of the following statements is correct with regards to heparin-induced thrombocytopaenia (HIT)?
Your Answer: HIT typically develops 5-10 days after starting heparin.
Explanation:Heparin-induced thrombocytopenia (HIT) is a prothrombotic disorder caused by antibodies that recognize complexes of platelet factor 4 (PF4) and heparin. HIT is frequently considered in the differential diagnosis of thrombocytopenia occurring in patients on heparin therapy. HIT is a challenging diagnosis because of routine heparin use in hospitalized patients, the common occurrence of thrombocytopenia. The process of heparin dependent IgG antibodies binding to heparin/platelet factor 4 complexes activates platelets and produces a hypercoagulable state. This syndrome typically develops 5-10 days (range 4-15 days) after heparin is commenced. It can occur with unfractionated heparin, low molecular weight heparin, or, rarely, fondaparinux. The diagnosis of HIT requires the combination of a compatible clinical picture and laboratory confirmation of the presence of heparin dependent platelet activating HIT antibodies. Discontinuation of heparin alone or initiation of a vitamin K antagonist alone like warfarin, is not sufficient to stop the development of thrombosis in patients with acute HIT. If there is moderate clinical suspicion for HIT, all sources of heparin must be discontinued and there must be consideration of anticoagulant treatment with a non-heparin drug.
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This question is part of the following fields:
- Cardiovascular
- Pharmacology
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Question 9
Incorrect
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Which of the following statements about vitamin B12 absorption is TRUE:
Your Answer: Intrinsic factor is produced by gastric chief cells.
Correct Answer: On ingestion, vitamin B12 is bound to R protein which protects it from digestion in the stomach.
Explanation:The substance intrinsic factor,essential for absorption of vitamin B12 in the ileum, issecreted by the parietal cells along with the secretion ofhydrochloric acid. When the acid-producing parietalcells of the stomach are destroyed, which frequentlyoccurs in chronic gastritis, the person develops not onlyachlorhydria (lack of stomach acid secretion) but oftenalso pernicious anaemia because of failure of maturationof the red blood cells in the absence of vitamin B12 stimulation of the bone marrow.
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This question is part of the following fields:
- Gastrointestinal
- Physiology
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Question 10
Correct
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Intrinsic factor is vital for gastrointestinal absorption of which of the following:
Your Answer: Vitamin B12
Explanation:Intrinsic factor is essential for the absorption of the small amounts of vitamin B12 normally present in the diet from the terminal ileum. The parietal cells of the stomach produce intrinsic factor, and following a gastrectomy, the absorption of vitamin B12 will be markedly reduced, and a deficiency state will exist.
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This question is part of the following fields:
- Gastrointestinal
- Physiology
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Question 11
Incorrect
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Which of the following movements is controlled by the pectoralis major muscle?
Your Answer: Extension, abduction and medial rotation of the humerus
Correct Answer: Flexion, adduction and medial rotation of the humerus
Explanation:The pectoralis major is a muscle that runs across the top of the chest and connects to a ridge on the back of the humerus (the bone of the upper arm). Adduction, or lowering, of the arm (opposed to the deltoideus muscle) and rotation of the arm forward around the axis of the body are two of its main functions.
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This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 12
Incorrect
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One of your patients has been infected by an obligate pathogen and presents with features of this condition.Which of these is an example of an obligate pathogen?
Your Answer: Pseudomonas aeruginosa
Correct Answer: Trepenoma pallidum
Explanation:Treponema pallidum is an obligate pathogen. Obligate pathogens are almost always associated with disease and usually cannot survive outside of the body for long periods of time. Examples include and HIV.Staphylococcus aureus and Bacteroides fragilis are conditional pathogens. These are pathogens that usually cause disease only if certain conditions are met.Pneumocystis jiroveci and Pseudomonas aeruginosa, are opportunistic pathogens. These are pathogens that can only cause disease in an immunocompromised host or under unusual circumstances.
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This question is part of the following fields:
- Microbiology
- Principles Of Microbiology
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Question 13
Incorrect
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Which of the following statements is correct with regards to Hodgkin's lymphoma?
Your Answer:
Correct Answer: Most patients present with painless asymmetrical lymphadenopathy, with cervical nodes involved most commonly.
Explanation:Lymphoma is a cancer of the lymphatic system, which is part of the body’s germ-fighting network. They are a group of diseases that are caused by malignant lymphocytes. These malignant cells accumulate in lymph nodes and other lymphoid tissue, giving rise to the characteristic clinical feature of lymphadenopathy. They can be subdivided into Hodgkin lymphoma (HL) which are characterised by the presence of Reed-Sternberg cells, and non-Hodgkin lymphoma (NHL). Characteristics of HL include:1. can present at any age but is rare in children and has a peak incidence in young adults, 2. almost 2:1 male predominance. 3. presents with painless, asymmetrical, firm and discrete enlargement of superficial lymph nodes. 4. cervical node involvement in 60-70% of cases, 5. axillary node involvement in 10-15% 6. inguinal node involvement in 6-12%. 7. modest splenomegaly during the course of the disease in 50% of patients8. may occasionally have liver enlargement9. bone marrow failure involvement is unusual in early disease. Approximately 85% of patients are cured, but the prognosis depends on age, stage and histology. Two well‐known but rare symptoms in HL are alcohol‐induced pain and pruritus.
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This question is part of the following fields:
- Haematology
- Pathology
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Question 14
Incorrect
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A 23-year-old has a known diagnosis of HIV. Blood is sent to the laboratory for tests.AIDS be diagnosed at a CD4 counts below?
Your Answer:
Correct Answer: 200 cells/mm 3
Explanation:A normal CD4 count ranges from 500-1000 cells/mm3.At CD4 count of less than 350 cells/mm3 treatment with anti-retroviral therapy should be considered.At a CD4 count of >200 cells/mm3 AIDS is diagnosed.
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This question is part of the following fields:
- Microbiology
- Specific Pathogen Groups
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Question 15
Incorrect
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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 16
Incorrect
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In the foetus at 4 months gestation, where does haematopoiesis mainly occur?
Your Answer:
Correct Answer: Liver and spleen
Explanation:The first place that haematopoiesis occurs in the foetus is in the yolk sac. Later on, it occurs in the liver and spleen, which are the major hematopoietic organs from about 6 weeks until 6 – 7 months gestation. At this point, the bone marrow becomes the most important site. Haemopoiesis is restricted to the bone marrow in normal childhood and adult life.
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This question is part of the following fields:
- Basic Cellular
- Physiology
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Question 17
Incorrect
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The functional residual capacity (FRC) will be increased in which of the following:
Your Answer:
Correct Answer: Emphysema
Explanation:Factors increasing FRC:EmphysemaAir trapping in asthmaAgeing (due to loss of elastic properties)Increasing height of patient
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This question is part of the following fields:
- Physiology
- Respiratory
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Question 18
Incorrect
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Which of the following acts to inhibit antidiuretic hormone (ADH) release from the posterior pituitary:
Your Answer:
Correct Answer: Atrial natriuretic peptide
Explanation:ADH release is inhibited by low plasma osmolality, alcohol, caffeine, glucocorticoids and atrial natriuretic peptide (ANP).ADH release is stimulated primarily by raised plasma osmolality detected by osmoreceptors in the anterior hypothalamus. Other factors that increase ADH release include: extracellular fluid volume depletion, angiotensin II, nausea, pain, stress, exercise, emotion, hypoglycaemia.
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This question is part of the following fields:
- Endocrine
- Physiology
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Question 19
Incorrect
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A tumour compresses the jugular foramen of a 50-year-old patient. Compression of several nerves in the jugular foramen will result in which of the following complications?
Your Answer:
Correct Answer: Loss of gag reflex
Explanation:The glossopharyngeal nerve, which is responsible for the afferent pathway of the gag reflex, the vagus nerve, which is responsible for the efferent pathway of the gag reflex, and the spinal accessory nerve all exit the skull through the jugular foramen. These nerves are most frequently affected if the jugular foramen is compressed. As a result, the patient’s gag reflex is impaired. The vestibulocochlear nerve is primarily responsible for hearing. The trigeminal nerve provides sensation in the face. The facial nerve innervates the muscles of face expression (including those responsible for closing the eye). Tongue motions are controlled mostly by the hypoglossal nerve.
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This question is part of the following fields:
- Anatomy
- Cranial Nerve Lesions
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Question 20
Incorrect
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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 21
Incorrect
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When a child has mumps, how long should he or she be off from school?
Your Answer:
Correct Answer: 5 days from onset of swelling
Explanation:To avoid the spread of infection, infected patients should be isolated. Patients should avoid going to school, childcare, or job for five days after the swelling has occurred.
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This question is part of the following fields:
- Microbiology
- Pathogens
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Question 22
Incorrect
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A 58-year-old man showing symptoms of increase in weight, proximal muscular weakening and withering, easy bruising, and acne. You notice that he has a full, plethoric aspect to his face, as well as significant supraclavicular fat pads, when you examine him. His blood pressure is 158/942 mmHg, and his glucose tolerance has lately been impaired. His potassium level is 3.2 mmol/L.What is the MOST LIKELY diagnosis?
Your Answer:
Correct Answer: Cushing’s syndrome
Explanation:Cushing’s syndrome is a group of symptoms and signs brought on by long-term exposure to high amounts of endogenous or exogenous glucocorticoids. Cushing’s syndrome affects about 10-15 persons per million, and it is more common in those who have had a history of obesity, hypertension, or diabetes.Cushing’s syndrome has a wide range of clinical manifestations that are dependent on the degree of cortisol overproduction. The appearance might be vague and the diagnosis difficult to detect when cortisol levels are just somewhat elevated. On the other hand, in long-term cases of severely increased cortisol levels, the presentation might be colourful and the diagnosis simple.Cushing’s syndrome has the following clinical features:Obesity and weight growth in the true senseSupraclavicular fat pads are fat pads that are located above the clavicle.Buffalo humpFullness and plethora of the face (‘moon facies’)Muscle atrophy and weakening at the proximal levelDiabetes mellitus, also known as impaired glucose toleranceHypertensionSkin thinning and bruisingDepressionHirsutismAcneOsteoporosisAmenorrhoea or oligomenorrhoeaCortisol 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 during the whole 24-hour period. In the morning, levels may be normal, but they may be high at night-time, when they are generally repressed. As a result, random cortisol testing is not an effective screening technique and is not advised.The following are the two most common first-line screening tests:Cortisol levels in the urine are measured every 24 hours.A diagnosis of Cushing’s syndrome can be made if more than two collections measure cortisol excretion more than three times the upper limit of normal.Physical stress (e.g., excessive exercise, trauma), mental stress (e.g., sadness), alcohol or drug misuse, complex diabetes, and pregnancy can all cause false positives.Renal dysfunction, inadequate collection, and cyclical Cushing’s disease can all cause false negatives.The overnight low-dose dexamethasone suppression test (LDDST) involves giving 1 mg of dexamethasone at 11 p.m. and measuring blood cortisol levels at 8 a.m. the next day.Cushing’s syndrome is diagnosed when cortisol is not suppressed to less than 50 nmol/L.It might be difficult to tell the difference between mild Cushing’s disease and normal cortisol production.False positives can occur as a result of depression, severe systemic sickness, renal failure, prolonged alcohol misuse, old age, and the use of hepatic enzyme-inducing medicines, among other things.False negatives are extremely uncommon in Cushing’s disease patients.A characteristic biochemical picture might also be helpful in confirming the diagnosis of Cushing’s syndrome. The following are the primary characteristics:HypokalaemiaAlkalosis metabolique
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This question is part of the following fields:
- Endocrine Physiology
- Physiology
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Question 23
Incorrect
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Which law describes the rate of diffusion in a solution?
Your Answer:
Correct Answer: Fick’s law
Explanation:Fick’s law describes the rate of diffusion in a solution. Fick’s law states that:Jx = -D A (ΔC / Δx)Where:Jx = The amount of substance transferred per unit timeD = Diffusion coefficient of that particular substanceA = Surface area over which diffusion occursΔC = Concentration difference across the membraneΔx = Distance over which diffusion occursThe negative sign reflects movement down the concentration gradient
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This question is part of the following fields:
- Basic Cellular Physiology
- Physiology
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Question 24
Incorrect
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A 30-year-old woman with type 1 diabetes mellitus is brought in drowsy and confused. Her BM is 2.2 mmol/l and a dose of IM glucagon is administered.What is the principal stimulus for the secretion of glucagon?
Your Answer:
Correct Answer: Hypoglycaemia
Explanation:Glucagon, a peptide hormone, is produced and secreted by alpha cells of the islets of Langerhans, located in the endocrine portion of the pancreas. Its main physiological role is stimulation of hepatic glucose output leading to increase in blood glucose. It is the major counter-regulatory hormone to insulin in maintaining glucose homeostasis.The principal stimulus for the secretion of glucagon is hypoglycaemia. Hypoglycaemia then stimulates:GlycogenolysisGluconeogenesisLipolysis in adipose tissue leading to increased glycaemia.Secretion of glucagon is also stimulated by arginine, alanine, adrenaline, acetylcholine and cholecystokininSecretion of glucagon is inhibited by:InsulinSomatostatinIncreased free fatty acidsIncreased urea production
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This question is part of the following fields:
- Endocrine Physiology
- Physiology
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Question 25
Incorrect
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Which of the following is an ECG change typically associated with hyperkalaemia:
Your Answer:
Correct Answer: Wide QRS complex
Explanation:Hyperkalaemia causes a rapid reduction in resting membrane potential leading to increased cardiac depolarisation and muscle excitability. This in turn results in ECG changes which can rapidly progress to ventricular fibrillation or asystole. Very distinctive ECG changes that progressively change as the K+level increases:K+>5.5 mmol/l – peaked T waves (usually earliest sign of hyperkalaemia), repolarisation abnormalitiesK+>6.5 mmol/l – P waves widen and flatten, PR segment lengthens, P waves eventually disappearK+>7.0 mmol/l – Prolonged QRS interval and bizarre QRS morphology, conduction blocks (bundle branch blocks, fascicular blocks), sinus bradycardia or slow AF, development of a sine wave appearance (a pre-terminal rhythm)K+>9.0 mmol/l – Cardiac arrest due to asystole, VF or PEA with a bizarre, wide complex rhythm.
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This question is part of the following fields:
- Physiology
- Renal
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Question 26
Incorrect
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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 27
Incorrect
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A new blood test is being developed to diagnose DVT. 1000 people presenting to ED with suspected DVT undergo the new blood test and the gold standard doppler ultrasound to confirm the diagnosis. Of the 1000 people, 77 are confirmed to have a DVT. Of the patients diagnosed with DVT, 75 test positive with the new diagnostic test and of the patients not diagnosed with DVT, 125 test positive with the new diagnostic test. What is the negative predictive value of this test:DVT YesDVT NoTotalPositive testa= 75b = 125200Negative testc = 2d = 798800Total779231000
Your Answer:
Correct Answer: 0.99
Explanation:Negative predictive value (NPV) is the proportion of individuals with a negative test result who do not have the disease.Negative predictive value (NPV) = d/(c+d) = 798/800 = 0.99 = 99%This means there is a 99% chance, if the test is negative, that the patient does not have a DVT.
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This question is part of the following fields:
- Evidence Based Medicine
- Statistics
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Question 28
Incorrect
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Regarding skeletal muscle contraction, which of the following statements is CORRECT:
Your Answer:
Correct Answer: The force of contraction of a muscle can be controlled by increasing recruitment of motor units.
Explanation:Each motor unit contracts in an all or nothing fashion, i.e. if a motor unit is excited, it will stimulate all of its muscle fibres to contract. The force of contraction of a muscle is controlled by varying the motor unit recruitment (spatial summation), and by varying the firing rate of the motor units (temporal summation). During a gradual increase in contraction of a muscle, the first units start to discharge and increase their firing rate, and, as the force needs to increase, new units are recruited and, in turn, also increase their firing rate. For most motor units, the firing rate for a steady contraction is between 5 and 8 Hz. Because the unitary firing rates for each motor unit are different and not synchronised, the overall effect is a smooth force profile from the muscle. Increasing the firing rate of motor units is temporal summation where the tension developed by the first action potential has not completely decayed when the second action potential and twitch is grafted onto the first and so on. If the muscle fibres are stimulated repeatedly at a faster frequency, a sustained contraction results where it is not possible to detect individual twitches. This is called tetanus.
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This question is part of the following fields:
- Basic Cellular
- Physiology
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Question 29
Incorrect
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Which of the following is NOT a notifiable disease:
Your Answer:
Correct Answer: HIV
Explanation:HIV mainly infects CD4+ T helper cells. Viral replication results in progressive T-cell depletion and impaired cell-mediated immunity with subsequent secondary opportunistic infections and increased risk of malignancy. B-cell function is also reduced as a result of lack of T-cell stimulation.HIV is not a notifiable disease.
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This question is part of the following fields:
- Infections
- Pharmacology
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Question 30
Incorrect
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A 53-year-old male has presented to your clinic with the complaint of a rash on his right forearm. On examination, you discover small reddish-purple spots on the skin measuring less than 2-3 mm. They do not blanch on applying pressure. Which one of the following best fits the description given above?
Your Answer:
Correct Answer: Petechiae
Explanation:Petechiae are small red or purple spots on the skin measuring less than 3 mm, caused by minor haemorrhages which do not blanch on applying pressure.Purpura measures between 3mm and 1 cm in diameter, while ecchymoses are greater than 1 cm in diameter. Both are caused due to haemorrhage. Erythema is the generalised redness of the skin. A macule is a flat, discoloured area of the skin measuring less than 1 cm in diameter.
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This question is part of the following fields:
- General Pathology
- Pathology
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SESSION STATS - PERFORMANCE PER SPECIALTY
