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Question 1
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: Staphylococcus aureus
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 2
Incorrect
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A 25-year-old man suffers from a shoulder injury that damaged the nerve that innervates the infraspinatus muscle.
Which of the following nerves may most likely be affected?Your Answer: The thoracodorsal nerve
Correct Answer: The suprascapular nerve
Explanation:The suprascapular nerve (C5-C6) innervates the infraspinatus. It originates at the superior trunk of the brachial plexus. It runs laterally across the lateral cervical region to supply the infraspinatus and also the supraspinatus.
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This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 3
Incorrect
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As part of his angina treatment, a 68-year-old man is prescribed a beta blocker. He starts having nightmares and has trouble sleeping soon after starting the beta-blocker.
Which of the beta blockers listed below is the most likely to be in his system?Your Answer: Nadolol
Correct Answer: Propranolol
Explanation:The beta-adrenoceptors in the heart, peripheral vasculature, bronchi, pancreas, and liver are blocked by beta-adrenoceptor blocking drugs (beta blockers).
Beta blockers come in a wide range of strengths, with the choice largely determined by the disease being treated and the patient’s unique circumstances. The intrinsic sympathomimetic activity, lipid solubility, duration of action, and cardioselectivity of beta blockers all differ.
Some beta blockers are lipid (lipophilic) soluble, while others are water soluble (hydrophilic). Drugs that are more lipid-soluble are absorbed faster from the gut, undergo more first-pass metabolism, and are eliminated faster. They’re also more likely to get into the brain and cause central effects like insomnia and nightmares. Propranolol, pindolol, labetalol, and metoprolol are examples of lipid-soluble beta blockers. Beta blockers that are water-soluble are less likely to enter the brain and are more resistant to first-pass metabolism. They are excreted by the kidneys, and in renal impairment, dosage reduction is frequently required. Atenolol, nadolol, celiprolol, and sotalol are examples of water-soluble beta blockers.
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This question is part of the following fields:
- Cardiovascular Pharmacology
- Pharmacology
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Question 4
Incorrect
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Fracture of the medial epicondyle would result to the following, except
Your Answer:
Correct Answer: Weakness of abduction of the thumb
Explanation:Thumb abduction is mediated by the abductor pollicis longus and brevis, which are innervated by the radial and median nerves, respectively.
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This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 5
Incorrect
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Regarding airway resistance, which of the following statements is CORRECT:
Your Answer:
Correct Answer: Airway resistance is predominantly determined by the radius of the airway as described by Poiseuille's law.
Explanation:Flow through airways is described by Darcy’s law which states that flow is directly proportional to the mouth-alveolar pressure gradient and inversely proportional to airway resistance. Airway resistance is primarily determined by the airway radius according to Poiseuille’s law, and whether the flow is laminar or turbulent. Parasympathetic stimulation causes bronchoconstriction and sympathetic stimulation causes bronchodilation, but mediated by beta2-adrenoceptors. Muscarinic antagonists e.g. ipratropium bromide cause bronchodilation.
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This question is part of the following fields:
- Physiology
- Respiratory
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Question 6
Incorrect
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What is the mechanism of action of captopril:
Your Answer:
Correct Answer: Inhibition of the conversion of angiotensin I to angiotensin II
Explanation:Angiotensin-converting enzyme inhibitors (ACE inhibitors) e.g. captopril inhibit the conversion of angiotensin I to angiotensin II, and thus have a vasodilatory effect, lowering both arterial and venous resistance. The cardiac output increases and, because the renovascular resistance falls, there is an increase in renal blood flow. This latter effect, together with reduced aldosterone release, increases Na+ and H2O excretion, contracting the blood volume and reducing venous return to the heart.
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This question is part of the following fields:
- Cardiovascular
- Pharmacology
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Question 7
Incorrect
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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 8
Incorrect
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A 22-year-old presents with acute severe asthma. He takes a drug prescribed by her GP but cannot recall the name and is receiving regular salbutamol nebulisers. His current potassium level is 2.8 mmol/l.
Which drug is least likely to have caused his hypokalaemia?
Your Answer:
Correct Answer: Spironolactone
Explanation:Serious hypokalaemia can occur in severe asthma and the effect can be potentiated by concomitant treatment with theophyllines like aminophylline, corticosteroids, thiazide and loop diuretics, and hypoxia. Plasma-potassium concentration should be monitored in severe asthma.
Spironolactone, a potassium-sparing diuretic, is not likely to have contributed to patients hypokalaemia.
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This question is part of the following fields:
- Pharmacology
- Respiratory Pharmacology
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Question 9
Incorrect
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Which segment of the colon is most likely to be affected in diverticulitis?
Your Answer:
Correct Answer: Sigmoid colon
Explanation:Diverticulitis refers to inflammation and infection associated with a diverticulum and is estimated to occur in 10% to 25% of people with diverticulosis. Peridiverticular and pericolic infection results from a perforation (either macroscopic or microscopic) of a diverticulum, which leads to contamination, inflammation, and infection. The spectrum of disease ranges from mild, uncomplicated diverticulitis that can be treated in the outpatient setting, to free perforation and diffuse peritonitis that requires emergency laparotomy. Most patients present with left sided abdominal pain, with or without fever, and leucocytosis. The most common location for diverticulitis is the sigmoid colon.
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This question is part of the following fields:
- Abdomen And Pelvis
- Anatomy
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Question 10
Incorrect
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Which of the following is NOT a function of antibodies:
Your Answer:
Correct Answer: Act as antigen receptors on T lymphocytes
Explanation:Antibodies:
Neutralise toxins and prevent attachment of pathogens
Target, opsonise or agglutinate (clump together) antigens for phagocytosis
Activate the complement cascade (leading to lysis or opsonisation of the pathogen)
Act as antigen receptors on B lymphocytes
Activate antibody-dependent cell-mediated cytotoxicity by natural killer (NK) cells or T cytotoxic cells
Provide mucosal immunity (IgA-mediated)
Stimulate degranulation of mast cells (IgE and IgG mediated)
Provide passive immunity to the newborn (through transplacental passage of IgG and secretion of IgA in breast milk) -
This question is part of the following fields:
- Immune Responses
- Pathology
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Question 11
Incorrect
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Regarding Legionella species which of the following statements is CORRECT:
Your Answer:
Correct Answer: They are Gram-negative organisms.
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 days
Cough (usually non-productive and occurs in approximately 90%)
Pleuritic chest pain
Haemoptysis
Headache
Nausea, vomiting and diarrhoea
Anorexia
Legionella 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. -
This question is part of the following fields:
- Microbiology
- Pathogens
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Question 12
Incorrect
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Which of the following muscles inserts into the patella?
Your Answer:
Correct Answer: The quadriceps femoris complex
Explanation:The quadriceps femoris muscle translates to “four-headed muscle” from Latin. It bears this name because it consists of four individual muscles; rectus femoris, vastus medialis, vastus lateralis, and vastus intermedius. Out of all four muscles, only the rectus femoris crosses both the hip and knee joints. The others cross only the knee joint. These muscles differ in their origin, but share a common quadriceps femoris tendon which inserts into the patella. The function of the quadriceps femoris muscle is to extend the leg at the knee joint and to flex the thigh at the hip joint.
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This question is part of the following fields:
- Anatomy
- Lower Limb
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Question 13
Incorrect
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An 80-year-old patient with a history of chronic heart failure presents to you. Examination reveals widespread oedema.
Which statement about plasma oncotic pressure (π p ) is true?Your Answer:
Correct Answer: The influence of π p on fluid movement is negligible if the capillary reflection co-efficient is 0.1
Explanation:Plasma oncotic pressure (πp) is typically 25-30 mmHg.
70% of π p is generated by albumin so Hypoalbuminemia will decrease π p
The osmotic power of albumin is enhanced by the Gibbs-Donnan effect.
The influence of π p on fluid movement is negligible if the capillary reflection coefficient is 0.1. Another way of saying a vessel is highly permeable is saying the reflection coefficient is close to 0.
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This question is part of the following fields:
- Cardiovascular Physiology
- Physiology
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Question 14
Incorrect
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A 34-year-old man presented to the emergency room after being involved in a road traffic accident. Upon observation and examination, it was noted that he was hypotensive and has muffled heart sounds. It was suspected that he has pericardial effusion, so an emergency pericardiocentesis was to be performed.
In performing pericardiocentesis for suspected pericardial effusion, which of the following anatomical sites are at risk of being punctured?Your Answer:
Correct Answer: 1 cm below the left xiphocostal angle
Explanation:Pericardiocentesis is a procedure done to remove fluid build-up in the sac around the heart known as the pericardium. The pericardium can be tapped from almost any reasonable location on the chest wall. However, for the usual blind pericardiocentesis, the subxiphoid approach is preferred. Ideally, 2-D echocardiography is used to guide needle insertion and the subsequent path of the needle/catheter.
In the subxiphoid approach, the needle is inserted 1 cm inferior to the left xiphocostal angle with an angle of 30 degrees from the patient’s chest with a direction towards the left mid-clavicle.
The fingers may sense a distinct give when the needle penetrates the parietal pericardium. Successful removal of fluid confirms the needle’s position.
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This question is part of the following fields:
- Abdomen And Pelvis
- Anatomy
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Question 15
Incorrect
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What is nimodipine used predominantly in the treatment of?
Your Answer:
Correct Answer: Prevention and treatment of vascular spasm following subarachnoid haemorrhage
Explanation:Nimodipine is a smooth muscle relaxant that is related to nifedipine, but the effects preferentially act on cerebral arteries. It is exclusively used for the prevention and treatment of vascular spasm after an aneurysmal subarachnoid haemorrhage.
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This question is part of the following fields:
- Cardiovascular
- Pharmacology
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Question 16
Incorrect
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Regarding bicarbonate handling by the proximal tubule, which of the following statements is CORRECT:
Your Answer:
Correct Answer: For each H + secreted into the lumen, one Na + and one HCO 3 - is reabsorbed into the plasma.
Explanation:About 80% of bicarbonate is reabsorbed in the proximal tubule. HCO3-is not transported directly, tubular HCO3-associates with H+secreted by epithelial Na+/H+antiporters to form carbonic acid (H2CO3) which readily dissociates to form carbon dioxide and water in the presence of carbonic anhydrase. CO2and water diffuse into the tubular cells, where they recombine to form carbonic acid which dissociates to H+and HCO3-. This HCO3-is transported into the interstitium largely by Na+/HCO3-symporters on the basolateral membrane (and H+is secreted back into the lumen). For each H+secreted into the lumen, one Na+and one HCO3-are reabsorbed into the plasma. H+is recycled so there is little net secretion of H+at this stage.
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This question is part of the following fields:
- Physiology
- Renal
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Question 17
Incorrect
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Which of the following muscles acts as an extensor of the shoulder joint?
Your Answer:
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 18
Incorrect
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Antinuclear antibodies (ANAs) also referred to as anti-nuclear factors (ANFs) are autoantibodies that bind to contents of the cell nucleus.
Which ONE of these statements about ANAs is true?Your Answer:
Correct Answer: They can be of any immunoglobulin class
Explanation:Anti-nuclear antibodies(ANAs) also referred to as anti-nuclear factors (ANFs) are autoantibodies that bind to contents of the cell nucleus. They can be of any immunoglobulin class.
CREST syndrome is usually associated with anti-centromere antibodies.
ELISA testing is cheaper but not the most accurate means of testing for ANAs. Indirect immunofluorescence testing is the most reliable.
Nucleolar staining is suggestive of scleroderma, while homogenous staining is suggestive of lupus.
Anti-dsDNA antibodies are found in 80 – 90% of patients with SLE
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This question is part of the following fields:
- General Pathology
- Pathology
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Question 19
Incorrect
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An 82 year old man taking warfarin as a maintenance medication comes in to your clinic because of an infection. Which antibiotic is the safest choice for this patient?
Your Answer:
Correct Answer: Cefalexin
Explanation:Alterations in the international normalized ratio (INR) brought about by the concurrent use of antibiotics and warfarin may result in either excessive clotting or excessive bleeding if they are deemed to have a high risk for interaction. As such, there should be careful consideration of the class of antibiotic to be used.
Antibiotics from the following drug classes should generally be avoided as they have a high risk for interaction with warfarin, possible enhancing the anticoagulant effects of warfarin resulting in bleeding: Fluoroquinolones (e.g. ciprofloxacin, levofloxacin), Macrolides (e.g. clarithromycin, erythromycin, azithromycin), Nitroimidazoles (e.g. metronidazole), Sulphonamides (e.g. co-trimoxazole, a combination of trimethoprim and sulfamethoxazole), Trimethoprim, Tetracyclines (e.g. doxycycline).
Low risk antibiotics that have low risk for interaction with warfarin includes cephalexin, from the cephalosporin class, and clindamycin which is a lincomycin.
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This question is part of the following fields:
- Cardiovascular
- Pharmacology
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Question 20
Incorrect
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A patient is found to be anaemic. Which one of the following blood results would favour a diagnosis of anaemia of chronic disease rather than iron deficiency:
Your Answer:
Correct Answer: Low total iron binding capacity (TIBC)
Explanation:Anaemia of chronic disease is one of the most common causes of normocytic anaemia. The anaemia is usually mild (Hb > 90 g/L) and non-progressive. Anaemia of chronic disease is usually associated with low serum iron, low transferrin saturation, and a low total iron binding capacity (TIBC) with normal or raised ferritin which differentiates it from iron deficiency anaemia.
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This question is part of the following fields:
- Haematology
- Pathology
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Question 21
Incorrect
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A 67-year-old woman complains of general malaise, nausea, and vomiting. She is perplexed and declares that everything 'looks yellow.' Her potassium level is 6.8 mmol/l, according to a blood test.
Which of the drugs listed below is most likely to be the cause of her symptoms?Your Answer:
Correct Answer: Digoxin
Explanation:Because digoxin has a narrow therapeutic index, it can cause toxicity both during long-term therapy and after an overdose. Even when the serum digoxin concentration is within the therapeutic range, it can happen.
Acute digoxin toxicity usually manifests itself within 2-4 hours of an overdose, with serum levels peaking around 6 hours after ingestion and life-threatening cardiovascular complications following 8-12 hours.
Chronic digoxin toxicity is most common in the elderly or those with impaired renal function, and it is often caused by a coexisting illness. The clinical signs and symptoms usually appear gradually over days to weeks.
The following are characteristics of digoxin toxicity:
Nausea and vomiting
Diarrhoea
Abdominal pain
Confusion
Tachyarrhythmias or bradyarrhythmias
Xanthopsia (yellow-green vision)
Hyperkalaemia (early sign of significant toxicity)Some precipitating factors are as follows:
Elderly patients
Renal failure
Myocardial ischaemia
Hypokalaemia
Hypomagnesaemia
Hypercalcaemia
Hypernatraemia
Acidosis
Hypothyroidism
Spironolactone
Amiodarone
Quinidine
Verapamil
Diltiazem -
This question is part of the following fields:
- Cardiovascular Pharmacology
- Pharmacology
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Question 22
Incorrect
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Which of the following laboratory findings is NOT typical of Hodgkin lymphoma:
Your Answer:
Correct Answer: Basophilia
Explanation:Features may include:Normochromic normocytic anaemia is most common; bone marrow failure involvement is unusual in early disease, but if it occurs bone marrow failure may develop with leucoerythroblastic anaemiaOne-third of patients have a neutrophilia; eosinophilia is frequentAdvanced disease is associated with lymphopenia and loss of cell-mediated immunityPlatelet count is normal or increased in early disease and reduced in later stagesESR and CRP are usually raised (ESR is useful in monitoring disease progress)Serum LDH is raised initially in 30-40% of casesDiagnosis is made by histological examination of an excised lymph nodeThe distinctive multinucleate polypoid RS cell is central to the diagnosis of the four classic types of HL (95% of cases)
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This question is part of the following fields:
- Haematology
- Pathology
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Question 23
Incorrect
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A 40-year-old man with reduced urine output, nausea, and confusion also has a 150% rise of creatinine from baseline over the past 7 days. A diagnosis of acute kidney injury (AKI) is made after more tests are done.
His AKI stage is?Your Answer:
Correct Answer: Stage 2
Explanation:This patient with a 150% rise of creatinine above baseline within 7 days has stage 2 Acute kidney injury (AKI).
AKI stages are as follows:
Stage 1
Creatinine rise of 26 micromole/L or more within 48 hours, or
Creatinine rise of 50-99% from baseline within 7 days (1.5-1.99 x baseline),or
Urine output <0.5 mL/kg/hour for more than 6 hours Stage 2
Creatinine rise of 100-199% from baseline within 7 days (2.0-2.99 x baseline),or
Urine output <0.5 mL/kg/hour for more than 12 hours Stage 3
Creatinine rise of 200% or more from baseline within 7 days (3.0 or more x baseline), or
Creatinine rise to 354 micromole/L or more with acute rise of 26 micromole/L or more within 48 hours or 50% or more rise within 7 days, or
Urine output <0.3 mL/kg/hour for 24 hours or anuria for 12 hours -
This question is part of the following fields:
- General Pathology
- Pathology
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Question 24
Incorrect
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What is the most common application of Nitrates?
Your Answer:
Correct Answer: Angina
Explanation:In patients with exertional stable angina, nitrates improve exercise tolerance, time to onset of angina, and ST-segment depression during exercise testing. In combination with beta-blockers or calcium channel blockers, nitrates produce greater anti-anginal and anti-ischemic effects.
While they act as vasodilators, coronary vasodilators, and modest arteriolar dilators, the primary anti ischemic effect of nitrates is to decrease myocardial oxygen demand by producing systemic vasodilation more than coronary vasodilation. This systemic vasodilation reduces left ventricular systolic wall stress. -
This question is part of the following fields:
- Cardiovascular
- Pharmacology
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Question 25
Incorrect
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You're called to a cardiac arrest in your Emergency Department resuscitation area. The rhythm strip is shown in the diagram below. Defibrillation has already been attempted three times on the patient. You intended to administer amiodarone, but your department has informed you that it is not available. In these circumstances, if amiodarone is not available, which of the following drugs is recommended by the ALS guidelines?
Your Answer:
Correct Answer: Lidocaine
Explanation:If amiodarone is unavailable in VF/pVT arrests, lidocaine at a dose of 1 mg/kg can be used instead, according to the latest ALS guidelines. If amiodarone has already been given, no lidocaine should be given.
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This question is part of the following fields:
- Cardiovascular Pharmacology
- Pharmacology
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Question 26
Incorrect
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A 35 year old man presents with a deep laceration to the proximal part of the forearm. On further assessment, the patient is unable to flex the metacarpophalangeal joints and interphalangeal joints of the index, middle finger and the thumb.
The ring and little fingers are intact but there is weakness at the proximal interphalangeal joint.
There is also loss of sensation over the lateral palm and the palmar surface of the lateral three and a half fingers.
Which of these nerve(s) has most likely been affected?
Your Answer:
Correct Answer: Median nerve
Explanation:A median nerve injury affecting the extrinsic and intrinsic muscles of the hand will present with:
Loss of sensation to the lateral palm and the lateral three and a half fingers.
Weakness of flexion at the metacarpophalangeal joints of the index and middle finger. This is because of paralysis of the lateral two lumbricals.
Weakness of flexion of the proximal interphalangeal joints of all four fingers due to paralysis of the flexor digitorum superficialis
Weakness of flexion at the distal interphalangeal joints of the index and middle finger following paralysis of the lateral half of the flexor digitorum profundus.
Weakness of thumb flexion, abduction and opposition due to paralysis of the flexor pollicis longus and thenar muscles -
This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 27
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) / R
Resistance 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 fluid
L = The length of the tube
R = The radius of the tube
Therefore, 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. -
This question is part of the following fields:
- Basic Cellular
- Physiology
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Question 28
Incorrect
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Haemophilia B results from a deficiency in:
Your Answer:
Correct Answer: Factor IX
Explanation:Haemophilia B is a bleeding disorder caused by a deficiency of clotting factor IX. It is the second commonest form of haemophilia, and is rarer than haemophilia A. Haemophilia B tends to be similar to haemophilia A but less severe. The two disorders can only be distinguished by specific coagulation factor assays.
The incidence is one-fifth of that of haemophilia A. Laboratory findings demonstrate prolonged APTT, normal PT and low factor IX.
Haemophilia B inherited in an X-linked recessive fashion, affecting males born to carrier mothers.
There is also a variation called Leyden, in which factor IX levels are below 1% until puberty, when they rise, potentially reaching as high as 40-60% of normal. This is thought to be due to the effects of testosterone at puberty. -
This question is part of the following fields:
- Haematology
- Pathology
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Question 29
Incorrect
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At rest, saliva is produced predominantly by which of the following:
Your Answer:
Correct Answer: Submandibular gland
Explanation:At rest, most saliva is produced by the submandibular gland (65%). When stimulated by the autonomic nervous system, about 50% of saliva is produced by the parotid gland with only 30% produced by the submandibular gland.
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This question is part of the following fields:
- Gastrointestinal
- Physiology
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Question 30
Incorrect
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A 30-year-old man presents with piriformis syndrome pain, tingling, and numbness in her buttocks. He noted that the pain gets worse upon sitting down. He was seen by a physiotherapist and a diagnosis of piriformis syndrome was made.
Which of the following nerves becomes irritated in piriformis syndrome?Your Answer:
Correct Answer: Sciatic nerve
Explanation:Piriformis syndrome is a clinical condition of sciatic nerve entrapment at the level of the ischial tuberosity. While there are multiple factors potentially contributing to piriformis syndrome, the clinical presentation is fairly consistent, with patients often reporting pain in the gluteal/buttock region that may shoot, burn or ache down the back of the leg (i.e. sciatic-like pain). In addition, numbness in the buttocks and tingling sensations along the distribution of the sciatic nerve is not uncommon.
The sciatic nerve runs just adjacent to the piriformis muscle, which functions as an external rotator of the hip. Hence, whenever the piriformis muscle is irritated or inflamed, it also affects the sciatic nerve, which then results in sciatica-like pain.
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This question is part of the following fields:
- Anatomy
- Lower Limb
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Question 31
Incorrect
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A 54 year old patient presents with vertigo, ipsilateral hemiataxia, dysarthria, ptosis and miosis.
Which of these blood vessels has most likely been occluded?
Your Answer:
Correct Answer: Posterior inferior cerebellar artery
Explanation:Posterior inferior cerebellar artery (PICA) occlusion is characterised by vertigo, ipsilateral hemiataxia, dysarthria, ptosis and miosis. PICA occlusion causes infarction of the posterior inferior cerebellum, inferior cerebellar vermis and lateral medulla.
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This question is part of the following fields:
- Anatomy
- Central Nervous System
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Question 32
Incorrect
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Which of the following could denote a diagnosis of acquired immunodeficiency syndrome (AIDS) in a patient infected with HIV:
Your Answer:
Correct Answer: CD4 count < 200 cells/uL
Explanation:A diagnosis of AIDS can be made in a patient infected with HIV if the patient has a CD4 count < 200 cells/uL, or an AIDS-defining illness. Antiretroviral treatment should be considered in patients with CD4 counts < 350 cells/uL.
Oral candidiasis is not an AIDS defining illness – candidiasis of the bronchi, trachea, lungs or of the oesophagus is an AIDS defining illness.
A positive p24 antigen test seen in early HIV infection and does not indicate the development of AIDS.
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This question is part of the following fields:
- Microbiology
- Pathogens
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Question 33
Incorrect
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Elevation of the eyeball is primarily produced by which of the following muscles:
Your Answer:
Correct Answer: Superior rectus and inferior oblique
Explanation:Elevation of the eyeball is produced by the superior rectus and the inferior oblique muscles.
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This question is part of the following fields:
- Anatomy
- Head And Neck
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Question 34
Incorrect
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An analytical study is conducted to compare the risk of stroke between Ticagrelor therapy and Warfarin therapy among patients with atrial fibrillation. The following is obtained from the study:
No. of patients who took Ticagrelor: 300
No. of patients who took Ticagrelor and suffered a stroke: 30
No. of patients who took Warfarin: 500
No. of patients who took Warfarin and suffered a stroke: 20
Compute for the absolute risk in the Ticagrelor group.Your Answer:
Correct Answer: 0.1
Explanation:The absolute risk (AR) is the probability or chance of an event. It is computed as the number of events in treated or control groups, divided by the number of people in that group.
AR = 30/300 = 0.1
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This question is part of the following fields:
- Evidence Based Medicine
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Question 35
Incorrect
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Which of the following is NOT a mineralocorticoid effect of corticosteroids:
Your Answer:
Correct Answer: Hyperglycaemia
Explanation:Mineralocorticoid side effects include:hypertensionsodium retentionwater retention and oedemapotassium losscalcium loss
Glucocorticoid side effects include:weight gainhyperglycaemia and diabetesosteoporosis and osteoporotic fracturesmuscle wasting (proximal myopathy)peptic ulceration and perforationpsychiatric reactions -
This question is part of the following fields:
- Endocrine
- Pharmacology
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Question 36
Incorrect
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Which of the following statements is considered correct regarding Klebsiella infections?
Your Answer:
Correct Answer: Klebsiella spp. are non-motile
Explanation:Klebsiella is a Gram-negative, rod-shaped, non-motile bacteria. The absence of motility distinguishes Klebsiella spp. from most other members of the family Enterobacteriaceae.
K. pneumoniae is the most commonly isolated species and has the distinct feature of possessing a large polysaccharide capsule. The capsule offers the organism protection against phagocytosis and antimicrobial absorption,
contributing to its virulence.Colonization of gram-negative bacilli in the respiratory tracts of hospitalized patients, particularly by K. pneumoniae, increases with the length of hospital stay. It is a frequent cause of lower respiratory tract infections among hospitalized patients and in immunocompromised hosts such as newborns,
elderly patients, and seriously ill patients on respirators. -
This question is part of the following fields:
- Microbiology
- Specific Pathogen Groups
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Question 37
Incorrect
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In the treatment of hypertensive episodes in pheochromocytoma, which of the following medication types is administered as first-line management:
Your Answer:
Correct Answer: Alpha-blockers
Explanation:The first line of management in controlling blood pressure and preventing intraoperative hypertensive crises is to use a combination of alpha and beta-adrenergic inhibition. In phaeochromocytoma, alpha-blockers are used to treat hypertensive episodes in the short term. Tachycardia can be managed by the careful addition of a beta-blocker, preferably a cardioselective beta-blocker, once alpha blockade has been established. Long term management of pheochromocytoma involves surgery.
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This question is part of the following fields:
- Cardiovascular
- Pharmacology
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Question 38
Incorrect
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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 virus
Varicella zoster virus
Mycobacterium tuberculosisThe following table summarises the various routes of transmission with example organisms:
Route of transmission
Example organisms
Aerosol (airborne particle < 5 µm)
Mycobacterium tuberculosis
Varicella zoster virus
Measles 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 39
Incorrect
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A 71-year-old man treated with antibiotics for a chest infection returns with a profuse, offensive smelling diarrhoea. A diagnosis of Clostridium difficile diarrhoea is made after investigations.
The action most effective at minimizing spread to other patients is?
Your Answer:
Correct Answer: Hand washing
Explanation:Clostridium difficile, a Gram-positive, anaerobic, spore forming bacteria is present in the gut of approximately 3% of healthy adults (2012 UK HPA estimates). Following use of broad spectrum antibiotics, which alter normal gut flora, Clostridium difficile associated diarrhoea (CDAD) occurs.
Alcohol hand gel is not effective against Clostridium Difficile spores. Hand washing with soap and water is very essential for healthcare workers who come in contact with it.
Wearing an apron and gloves, and isolation to a side room are important contact precautions. They are, however, ineffective if hand washing is neglected.
Although oral vancomycin is the first-line treatment for C. difficile associated diarrhoea, it will not limit patient to patient spread.
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This question is part of the following fields:
- Microbiology
- Specific Pathogen Groups
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Question 40
Incorrect
SESSION STATS - PERFORMANCE PER SPECIALTY
