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Question 1
Correct
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What is the mechanism of action of penicillin antibiotics:
Your Answer: Inhibition of bacterial cell wall synthesis
Explanation:Penicillins and the other ß-lactam antibiotics are bactericidal. They produce their antimicrobial action by preventing cross-linkage between the linear peptidoglycan polymer chains that make up the bacterial cell wall. They, therefore, inhibit cell wall synthesis.
The integrity of the ß-lactam ring is essential for antimicrobial activity. Many bacteria (including most Staphylococci) are resistant to benzylpenicillin and phenoxymethylpenicillin because they produce enzymes (penicillinases, ß-lactamases) that open the ß-lactam ring. -
This question is part of the following fields:
- Infections
- Pharmacology
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Question 2
Incorrect
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Flucloxacillin is used first line for all of the following infections EXCEPT for:
Your Answer:
Correct Answer: Otitis media
Explanation:Flucloxacillin is used first line for treatment of widespread impetigo infection, cellulitis, mastitis, osteomyelitis, septic arthritis, severe erysipelas, severe/spreading otitis externa and infective endocarditis caused by staphylococci. Amoxicillin is first line for acute otitis media.
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This question is part of the following fields:
- Infections
- Pharmacology
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Question 3
Incorrect
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Amoxicillin is used first line for all of the following infections EXCEPT for:
Your Answer:
Correct Answer: Cellulitis
Explanation:Amoxicillin is used first line for low to moderate severity community acquired pneumonia, exacerbations of chronic bronchitis, for acute otitis media, for acute sinusitis, for oral infections/dental abscess, for Listeria meningitis (in combination with another antibiotic), for infective endocarditis (in combination with another antibiotic) and for H. Pylori eradication (in combination with metronidazole/clarithromycin and a PPI). Flucloxacillin is used first line for acute cellulitis.
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This question is part of the following fields:
- Infections
- Pharmacology
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Question 4
Incorrect
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On ambulatory blood pressure monitoring, a 48-year-old Caucasian man has an average BP reading of 152/96 mmHg (ABPM).
Which of the following would be the patient's first-line drug treatment?Your Answer:
Correct Answer: Ramipril
Explanation:An ambulatory blood pressure reading of >150/95 is classified as stage 2 hypertension, according to the NICE care pathway for hypertension, and the patient should be treated with an antihypertensive drug.
A calcium-channel blocker, such as amlodipine, would be the most appropriate medication for a 48-year-old Afro-Caribbean man.
An ACE inhibitor, such as ramipril, or a low-cost angiotensin-II receptor blocker (ARB), such as losartan, would be the most appropriate medication for a 48-year-old Caucasian man.
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This question is part of the following fields:
- Cardiovascular Pharmacology
- Pharmacology
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Question 5
Incorrect
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A 68-year-old female has presented to the Emergency Department with chest pain, palpitations, and breathlessness complaints. On ECG, she is diagnosed with ventricular arrhythmia and is administered lidocaine.
Which of the following is the correct mechanism of action of lidocaine?Your Answer:
Correct Answer: Blocks Na+ channels in the heart
Explanation:Lidocaine is a tertiary amide local anaesthetic and also a class IV antiarrhythmic.
Like other local anaesthetics, lidocaine works on the voltage-gated sodium ion channel on the nerve cell membranes. It works in the following steps:
1. diffuses through neural sheaths and the axonal membrane into the axoplasm
2. binds fast voltage-gated Na+ channels in the neuronal cell membrane and inactivates them
3. With sufficient blockage, the membrane of the postsynaptic neuron will not depolarise and will be unable to transmit an action potential, thereby preventing the transmission of pain signalsThe same principle applies to Lidocaine’s actions in the heart as it blocks the sodium channels in the conduction system and the myocardium. This raises the threshold for depolarizing, making it less likely for the heart to initiate or conduct any action potential that can cause arrhythmia.
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This question is part of the following fields:
- Cardiovascular Pharmacology
- Pharmacology
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Question 6
Incorrect
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Which of the following cytokines is important for the maintenance of granulomatous inflammation:
Your Answer:
Correct Answer: TNF-alpha
Explanation:Granulomatous inflammation is a distinctive pattern of chronic inflammation that is encountered in a limited number of infectious and some non-infectious conditions. Briefly, a granuloma is a cellular attempt to contain an offending agent that is difficult to eradicate. In this attempt, there is often strong activation of T lymphocytes leading to macrophage activation, which can cause injury to normal tissues. IL-1 is important in initiating granuloma formation, IL-2 can cause them to enlarge and TNF-α maintains them.
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This question is part of the following fields:
- Inflammatory Responses
- Pathology
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Question 7
Incorrect
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You are giving a presentation on the immune system as part of your peer-to-peer teaching sessions. Yu are currently discussing phagocytes. Macrophages are derived from which of the following cells:
Your Answer:
Correct Answer: Monocytes
Explanation:Monocytes spend only a short time in the marrow and, after circulating for 20-40 hours, leave the blood to enter the tissues where they become macrophages. Macrophages form the reticuloendothelial system in the liver, spleen and lymph nodes. The lifespan of macrophages may be as long as several months or even years. In tissues the macrophages become self-replicating without replenishment from the blood. They assume specific functions in different tissues e.g. dendritic cells which are involved in antigen presentation to T-cells. Macrophages may be activated by cytokines such as IFN-gamma, contact with complement or direct contact with the target cell through leucocyte adhesion molecules.
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This question is part of the following fields:
- Immune Responses
- Pathology
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Question 8
Incorrect
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Which of these drugs may reduce the efficacy of contraception?
Your Answer:
Correct Answer: Carbamazepine
Explanation:Antiepileptic medications such as carbamazepine (Tegretol), topiramate (Topamax), and phenytoin (Dilantin) are widely known for reducing the contraceptive effectiveness of OCPs.
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This question is part of the following fields:
- Central Nervous System
- Pharmacology
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Question 9
Incorrect
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Funnel plots are typically used to display:
Your Answer:
Correct Answer: The existence of publication bias in meta-analysis
Explanation:Funnel plots are used to demonstrate the existence of publication bias in meta-analysis. Funnel plots are scatter plots of treatment effects estimated from individual studies on the x axis and some measure of study size on the y axis. Each point on the graph represents one of the studies. A symmetrical inverted funnel shape indicates an absence of publication bias. If there is publication bias, there will be asymmetry of the open wide end due to the absence of small negative results.
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This question is part of the following fields:
- Evidence Based Medicine
- Study Methodology
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Question 10
Incorrect
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A 60-year-old patient with a history of hypertension and chronic kidney disease (CKD) walks into the clinic to discuss her most recent blood results indicating an accelerated progression of CKD.
Which of the following is the correct definition for accelerated progression of CKD?
Your Answer:
Correct Answer: A sustained decrease in GFR of 15 ml/minute/1.73 m 2 per year
Explanation:Chronic kidney disease (CKD) is a disorder in which kidney function gradually deteriorates over time. It’s fairly prevalent, and it typically remains unnoticed for years, with only advanced stages of the disease being recognized. There is evidence that medication can slow or stop the progression of CKD, as well as lessen or prevent consequences and the risk of cardiovascular disease (CVD).
CKD is defined as kidney damage (albuminuria) and/or impaired renal function (GFR 60 ml/minute per 1.73 m2) for three months or longer, regardless of clinical diagnosis.
A prolonged decline in GFR of 25% or more with a change in GFR category within 12 months, or a sustained drop in GFR of 15 ml/minute/1.73 m² per year, is considered accelerated CKD progression.
End-stage renal disease (ESRD) is defined as severe irreversible kidney impairment with a GFR of less than 15 ml/minute per 1.73 m² and a GFR of less than 15 ml/minute per 1.73 m². -
This question is part of the following fields:
- Physiology
- Renal Physiology
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Question 11
Incorrect
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Which of the following is the most likely causative organism of acute epiglottitis in a 6 year old?
Your Answer:
Correct Answer: Streptococcus pneumoniae
Explanation:Since the introduction of the HIB vaccine, most cases of acute epiglottitis are now caused by Streptococcus spp. The condition is now rare in children.
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This question is part of the following fields:
- Microbiology
- Specific Pathogen Groups
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Question 12
Incorrect
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A CT pulmonary angiography of a patient with a massive pulmonary embolus will most likely show which of the following signs?
Your Answer:
Correct Answer: Increased alveolar dead space
Explanation:A CT pulmonary angiogram is an angiogram of the blood vessels of the lungs. It is a diagnostic imaging test used to check for pulmonary embolism.
A pulmonary embolism is caused by a blood clot or thrombus that has become lodged in an artery in the lung and blocks blood flow to the lung. A patient with pulmonary embolism may feel an abrupt onset of pleuritic chest pain, shortness of breath, and hypoxia. Also, pulmonary embolism can result in alveolar dead space.
Dead space represents the volume of ventilated air that does not participate in gas exchange. The alveolar dead space is caused by ventilation/perfusion imbalances in the alveoli. It is defined as the sum of the volumes of alveoli that are ventilated but not perfused.
Aside from pulmonary embolism, smoking, bronchitis, emphysema, and asthma are among the other causes of alveolar dead space.
The other types of dead space are the following: Anatomical dead space is the portion of the airways that conducts gas to the alveoli. This is usually around 150 mL, and there is no possibility of gas exchange in these areas. Physiological dead space is the sum of anatomical and alveolar dead spaces.
Physiological dead space can account for up to 30% of the tidal volume.
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This question is part of the following fields:
- Physiology
- Respiratory Physiology
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Question 13
Incorrect
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Which of the following statements is correct about the extensor digitorum muscle?
Your Answer:
Correct Answer: It extends the medial four digits at the metacarpophalangeal joints
Explanation:Extensor digitorum is a long muscle located in the posterior compartment of the forearm. Together with the extensor carpi ulnaris and extensor digiti minimi, extensor carpi radialis longus and brevis as well as the brachioradialis, it belongs to the group of superficial extensors of the forearm. These muscles can be easily palpated in the lateral aspect of the posterior forearm, especially during the extension of hand when they are contracted.
Extensor digitorum runs from the lateral epicondyle of humerus to the medial four phalanges of the hand. In this way, it generates the pull for the extension of the four medial fingers in their metacarpophalangeal and both interphalangeal joints. Extensor digitorum also participates in the extension of the wrist.
Extensor digitorum is innervated by posterior interosseous nerve which is a continuation of a deep branch of radial nerve (root value C7 and C8).
Extensor digitorum is vascularized by the branches of three different arteries: (1) posterior interosseous artery, (2) radial recurrent artery, and (3) anterior interosseous artery. Anterior and posterior interosseous arteries are the branches of the common interosseous artery that arises from the ulnar artery. The radial recurrent artery is a 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 14
Incorrect
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Regarding flucloxacillin, which of the following statements is CORRECT:
Your Answer:
Correct Answer: It is resistant to bacterial beta-lactamases.
Explanation:Flucloxacillin is unique in that it is beta-lactamase stable and it can be used in infections caused by beta-lactamase producing staphylococci e.g. S. aureus. It is acid-stable and can therefore be given by mouth as well as by injection. It is used first line for treatment of widespread impetigo infection, cellulitis, mastitis, osteomyelitis, septic arthritis, severe erysipelas, severe/spreading otitis externa and infective endocarditis caused by staphylococci. The most common adverse effects of flucloxacillin include nausea, vomiting, skin rash, and diarrhoea. Cholestatic jaundice and hepatitis may occur very rarely, up to two months after treatment with flucloxacillin has been stopped. Administration for more than 2 weeks and increasing age are risk factors. First line treatment of animal and human bites is co-amoxiclav.
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This question is part of the following fields:
- Infections
- Pharmacology
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Question 15
Incorrect
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Regarding haemoglobin, which of the following statements is INCORRECT:
Your Answer:
Correct Answer: Haemoglobin synthesis occurs in mature erythrocytes.
Explanation:Haemoglobin is composed of four polypeptide globin chains each with its own iron containing haem molecule. Haem synthesis occurs largely in the mitochondria by a series of biochemical reactions commencing with the condensation of glycine and succinyl coenzyme A under the action of the key rate-limiting enzyme delta-aminolevulinic acid (ALA) synthase. The globin chains are synthesised by ribosomes in the cytosol. Haemoglobin synthesis only occurs in immature red blood cells.
There are three types of haemoglobin in normal adult blood: haemoglobin A, A2 and F:
– Normal adult haemoglobin (HbA) makes up about 96 – 98 % of total adult haemoglobin, and consists of two alpha (α) and two beta (β) globin chains.
– Haemoglobin A2 (HbA2), a normal variant of adult haemoglobin, makes up about 1.5 – 3.5 % of total adult haemoglobin and consists of two α and two delta (δ) globin chains.
– Foetal haemoglobin is the main Hb in the later two-thirds of foetal life and in the newborn until approximately 12 weeks of age. Foetal haemoglobin has a higher affinity for oxygen than adult haemoglobin.
Red cells are destroyed by macrophages in the liver and spleen after , 120 days. The haem group is split from the haemoglobin and converted to biliverdin and then bilirubin. The iron is conserved and recycled to plasma via transferrin or stored in macrophages as ferritin and haemosiderin. An increased rate of haemoglobin breakdown results in excess bilirubin and jaundice. -
This question is part of the following fields:
- Basic Cellular
- Physiology
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Question 16
Incorrect
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An 11-year-old boy was brought to the emergency room due to fever and pain in the ears. Upon physical examination, it was observed that the mastoid area is erythematous and there is a presence of a boggy, tender mass. A diagnosis of acute mastoiditis was made.
Which of the following parts of the temporal bone is most likely involved?Your Answer:
Correct Answer: Petrous part
Explanation:Mastoiditis is the inflammation of a portion of the temporal bone referred to as the mastoid air cells. The mastoid air cells are epithelium lined bone septations that are continuous with the middle ear cavity.
The temporal bone is composed of four parts: the mastoid process, the petrous pyramid, the squamous, and tympanic portions. The mastoid process and the petrous pyramid are the portions of particular interest because of the prevalence of suppurations within these parts of the temporal bone.
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This question is part of the following fields:
- Anatomy
- Head And Neck
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Question 17
Incorrect
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Which one of the listed cells are typically found in a granuloma?
Your Answer:
Correct Answer: Epithelioid cells
Explanation:Typically, a granuloma has Langhan’s cells (large multinucleated cells) surrounded by epithelioid cell aggregates, T lymphocytes and fibroblasts.
Antigen presenting monocytic cells are found in the skin are known as Langerhan’s cells.
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This question is part of the following fields:
- General Pathology
- Pathology
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Question 18
Incorrect
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Ipratropium bromide should be used with caution in patients with which of the following conditions:
Your Answer:
Correct Answer: Prostatic hyperplasia
Explanation:Ipratropium bromide is an antimuscarinic drug used in the management of acute asthma and COPD. It can provide short-term relief in chronic asthma, but short-acting β2agonists act more quickly and are preferred.
The BTS guidelines recommend that nebulised ipratropium bromide (0.5 mg 4-6 hourly) can be added to β2agonist treatment for patients with acute severe or life-threatening asthma or those with a poor initial response to β2 agonist therapy.
The aerosol inhalation of ipratropium can be used for short-term relief in mild chronic obstructive pulmonary disease in patients who are not already using a long-acting antimuscarinic drug (e.g. tiotropium).Its maximum effect occurs 30-60 minutes after use; its duration of action is 3-6 hours, and bronchodilation can usually be maintained with treatment three times per day.
The commonest side effect of ipratropium bromide is dry mouth. It can also trigger acute closed-angle glaucoma in susceptible patients. Tremor is commonly seen with β2agonists but not with antimuscarinics. Ipratropium bromide should be used with caution in: Men with prostatic hyperplasia and bladder-outflow obstruction (worsened urinary retention has been reported in elderly men), People with chronic kidney disease (CKD) stages 3 and above (because of the risk of drug toxicity), People with angle-closure glaucoma (nebulised mist of antimuscarinic drugs can precipitate or worsen acute angle-closure glaucoma) -
This question is part of the following fields:
- Pharmacology
- Respiratory
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Question 19
Incorrect
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A 18 year old student presents to ED with a headache, fever and photophobia. You suspect meningitis and agree to observe your junior performing a lumbar puncture. What is the highest safest vertebral level to perform lumbar puncture in adults:
Your Answer:
Correct Answer: L3/L4
Explanation:In adults, the spinal cord typically ends between L1/L2 whereas the subarachnoid space extends to approximately the lower border of vertebra S2. Lumbar puncture is performed in the intervertebral space L4/L5 or L3/L4.
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This question is part of the following fields:
- Anatomy
- Head And Neck
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Question 20
Incorrect
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On her most recent blood tests, a 55 year-old female with a history of hypertension was discovered to be hypokalaemic. She is diagnosed with primary hyperaldosteronism.
Which of the following is a direct action of aldosterone?
Your Answer:
Correct Answer: Secretion of H + into the distal convoluted tubule
Explanation:Aldosterone is a steroid hormone produced in the adrenal cortex’s zona glomerulosa. It is the most important mineralocorticoid hormone in the control of blood pressure. It does so primarily by promoting the synthesis of Na+/K+ATPases and the insertion of more Na+/K+ATPases into the basolateral membrane of the nephron’s distal tubules and collecting ducts, as well as stimulating apical sodium and potassium channel activity, resulting in increased sodium reabsorption and potassium secretion. This results in sodium conservation, potassium secretion, water retention, and a rise in blood volume and blood pressure.
Aldosterone is produced in response to the following stimuli:
Angiotensin II levels have risen.
Potassium levels have increased.
ACTH levels have risen.
Aldosterone’s principal actions are as follows:
Na+ reabsorption from the convoluted tubule’s distal end
Water resorption from the distal convoluted tubule (followed by Na+)
Cl is reabsorbed from the distal convoluted tubule.
K+ secretion into the convoluted distal tubule’s
H+ secretion into the convoluted distal tubule’s -
This question is part of the following fields:
- Physiology
- Renal Physiology
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Question 21
Incorrect
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Which of the following is not true regarding the structure and function of glomerular filtration membrane?
Your Answer:
Correct Answer: The absence of a basement membrane reduces impedance to filtration
Explanation:The glomerular filtration membrane is composed of fenestrated capillary endothelium, basement membrane, and filtration slits. It is an organized, semipermeable membrane preventing the passage of most of the proteins into the urine.
The anatomical arrangement of the glomerular filtration membrane maximizes the surface area available for filtration. The arrangement of its arterioles results in high hydrostatic pressures and facilitates filtration.
Fenestrated capillary endothelium of the glomerular filtration membrane is with relatively large pores. It allows the free movement of plasma proteins and solutes but still restricts the movement of blood cells.
Filtration slits are the smallest filters and restrict the movement of plasma proteins but still allow free movement of ions and nutrients.
The glomerular basement membrane (GBM) is a critical component of the glomerular filtration membrane. Thus, it is not true that its absence will reduce the resistance of flow. The basement membrane is true to be more selective and contains negatively charged glycoproteins. However, it still allows free passage of water, nutrients, and ions. Severe structural abnormalities of the GBM can result in protein (albumin) leakage.
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This question is part of the following fields:
- Physiology
- Renal Physiology
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Question 22
Incorrect
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You are about to perform a blood test on a patient suspected of having systemic lupus erythematosus. Which antibodies will indicate a positive result of systemic lupus erythematosus?
Your Answer:
Correct Answer: Anti-nuclear antibodies
Explanation:Antinuclear antibodies (ANA) are autoantibodies to the cells’ nucleus.
The ANA test is the most sensitive diagnostic test for verifying the disease’s diagnosis.
Other autoantibodies that may be found in SLE patients include rheumatoid factor, antiphospholipid antibodies, and antimitochondrial antibodies.
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This question is part of the following fields:
- Inflammatory Responses
- Pathology
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Question 23
Incorrect
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All of the following statements regarding Helicobacter pylori is considered true, except:
Your Answer:
Correct Answer: Serum antibody levels should be used to check for successful eradication
Explanation:Helicobacter pylori is a curved, non-spore forming, Gram-negative bacteria that is primarily linked to gastric infections. Once acquired, it colonizes the stomach for a long time and can cause a low-grade inflammatory process, producing a chronic superficial gastritis.
H. pylori can be recovered from gastric biopsy materials. Samples must be transported quickly to the laboratory.
Helicobacter infections usually are identified by nonculture methods. H. pylori can be presumptively identified in a gastric biopsy specimen by testing for the presence of a rapid urease reaction.Serologic testing is an important screening method for the diagnosis of H. pylori infection. It can also be diagnosed by faecal antigen detection, microscopic examination of stained gastric tissue, and DNA amplification tests.
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This question is part of the following fields:
- Microbiology
- Specific Pathogen Groups
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Question 24
Incorrect
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Regarding the penis, which of the following statements is CORRECT:
Your Answer:
Correct Answer: The corpus spongiosum is ventral in the erect penis.
Explanation:Because the anatomical position of the penis is erect, the paired corpora cavernosa are defined as dorsal in the body of the penis and the single corpus spongiosum as ventral. The nerves and vessels lie superficial to the corpus cavernosum. The urethra lies within the corpus spongiosum.
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This question is part of the following fields:
- Abdomen
- Anatomy
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Question 25
Incorrect
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You review a patient with urinary sepsis and decide to start her on gentamicin.
Which statement about gentamicin is true?
Your Answer:
Correct Answer: Ototoxicity is a dose-related effect
Explanation:Gentamicin, an aminoglycoside antibiotic, acts by binding to the 30S subunit of the bacterial ribosome inhibiting the binding of aminoacyl-tRNA, and thus prevents initiation of protein synthesis.
Gentamicin is given by injection because it is NOT absorbed orally.
It is excreted in the kidneys by glomerular filtration
Gentamicin is not to be used for the treatment of Neisseria meningitidis, Neisseria gonorrhoea, or Legionella pneumophila.There is a risk of patient going into shock from lipid A endotoxin release.
Two of its most notable side effects are hearing loss reversible nephrotoxicity and which are both dose-related and levels should be monitored in patients.
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This question is part of the following fields:
- Infections
- Pharmacology
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Question 26
Incorrect
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Which of the following drugs decreases plasma-theophylline levels:
Your Answer:
Correct Answer: Carbamazepine
Explanation:Examples of enzyme-inhibiting drugs (raise plasma theophylline level):
Erythromycin
Clarithromycin
Ciprofloxacin
Fluconazole
Verapamil
Allopurinol
Cimetidine
Examples of enzyme-inducing drugs (lower plasma theophylline level):
Primidone
Phenobarbital
Carbamazepine
Phenytoin
Ritonavir
Rifampicin
St John’s Wort -
This question is part of the following fields:
- Pharmacology
- Respiratory
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Question 27
Incorrect
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Polyuria and polydipsia develop in a patient with a history of affective disorder, who has been on long-term lithium treatment. She has a fluid deprivation test done because she is suspected of having nephrogenic diabetic insipidus. Which of the following urine osmolality findings would be the most reliable in confirming the diagnosis?
Your Answer:
Correct Answer: After fluid deprivation <300 mosmol/kg, after IM desmopressin >800 mosmol/kg
Explanation:The inability to produce concentrated urine is a symptom of diabetes insipidus. Excessive thirst, polyuria, and polydipsia are all symptoms of this condition. There are two forms of diabetes insipidus: Nephrogenic diabetes insipidus and cranial (central) diabetes insipidus.
A lack of ADH causes cranial diabetic insipidus. Patients with cranial diabetes insipidus can have a urine output of up to 10-15 litres per 24 hours, however most patients can maintain normonatraemia with proper fluid consumption. Thirty percent of cases are idiopathic, while another thirty percent are caused by head injuries. Neurosurgery, brain tumours, meningitis, granulomatous disease (e.g. sarcoidosis), and medicines like naloxone and phenytoin are among the other reasons. There is also a very rare hereditary type that is linked to diabetes, optic atrophy, nerve deafness, and bladder atonia.
Renal resistance to the action of ADH causes nephrogenic diabetes insipidus. Urine output is significantly increased, as it is in cranial diabetes insipidus. Secondary polydipsia can keep serum sodium levels stable or raise them. Chronic renal dysfunction, metabolic diseases (e.g., hypercalcaemia and hypokalaemia), and medications, such as long-term lithium use and demeclocycline, are all causes of nephrogenic diabetes insipidus.
The best test to establish if a patient has diabetes insipidus vs another cause of polydipsia is the water deprivation test, commonly known as the fluid deprivation test. It also aids in the distinction between cranial and nephrogenic diabetes insipidus. Weight, urine volume, urine osmolality, and serum osmolality are all measured after patients are denied water for up to 8 hours. At the end of the 8-hour period, 2 micrograms of IM desmopressin is given, and measures are taken again at 16 hours.
The following are the way results are interpreted:
Urine osmolality after fluid deprivation : Urine osmolality after IM desmopressin
Cranial diabetes insipidus: <300 mosmol/kg : >800 mosmol/kg
Nephrogenic diabetes insipidus: <300 mosmol/kg : <300 mosmol/kg
Primary polydipsia: >800 mosmol/kg : >800 mosmol/kg -
This question is part of the following fields:
- Physiology
- Renal Physiology
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Question 28
Incorrect
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A 50-year-old man, known hypertensive on amlodipine has been visiting his GP with symptoms of headache, tiredness, and muscle weakness. His blood test today shows a low potassium level of 2.8 mmol/L, and a slightly raised sodium level at 147 mmol/L.
What is the MOST LIKELY diagnosis?
Your Answer:
Correct Answer: Conn’s syndrome
Explanation:When there are excessive levels of aldosterone independent of the renin-angiotensin aldosterone axis, primary hyperaldosteronism occurs. Secondary hyperaldosteronism occurs due to high renin levels.
Causes of primary hyperaldosteronism include:
Conn’s syndrome
Adrenal hyperplasia
Adrenal cancer
Familial aldosteronismCauses of secondary hyperaldosteronism include:
Renal vasoconstriction
Oedematous disorders
Drugs – diuretics
Obstructive renal artery diseaseAlthough patients are usually asymptomatic, when clinical features are present, classically hyperaldosteronism presents with:
Hypokalaemia
Sodium levels can be normal or slightly raised
Hypertension
Metabolic alkalosis
Less common, clinical features are:
Lethargy
Headaches
Intermittent paraesthesia
Polyuria and polydipsia
Muscle weakness (from persistent hypokalaemia)
Tetany and paralysis (rare) -
This question is part of the following fields:
- Endocrine Physiology
- Physiology
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Question 29
Incorrect
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A blood test of a 7-year-old child with a 6-day history of bloody diarrhoea reveals a low platelet count, anaemia, and impaired kidney function. What bacteria is suspected of causing such a condition?
Your Answer:
Correct Answer: Escherichia coli
Explanation:Escherichia coli produces shiga toxin that causes diarrhoea, hemorrhagic colitis, and haemolytic uremic syndrome.
Haemolytic uremic syndrome is characterized by anaemia, thrombocytopenia, and acute renal failure. Transmission of E. coli is possible after consuming contaminated, undercooked drinks and foods. E. coli enters the body via the faecal-oral pathway.
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This question is part of the following fields:
- Microbiology
- Pathogens
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Question 30
Incorrect
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Which of the following clinical features would you least expect to see in a lesion of the frontal lobe:
Your Answer:
Correct Answer: Contralateral homonymous hemianopia with macular sparing
Explanation:Contralateral homonymous hemianopia with macular sparing results from damage to the primary visual cortex of the occipital lobe. Incontinence may occur due to damage of the cortical micturition centre in the prefrontal cortex. Primitive reflexes and inability to problem solve may occur due to damage to the prefrontal cortex. Motor weakness of the contralateral limb with UMN signs may occur due to damage of the primary motor cortex.
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This question is part of the following fields:
- Anatomy
- Central Nervous System
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SESSION STATS - PERFORMANCE PER SPECIALTY
