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Question 1
Correct
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Regarding acute idiopathic thrombocytopaenic purpura (ITP), which of the following statements is CORRECT:
Your Answer: Over 80% of children recover without treatment.
Explanation:Acute ITP is most common in children. In approximately 75% of cases, the episode follows vaccination or infection such as chicken pox or glandular fever. Most cases are caused by non-specific immune complex attachment to platelets. Acute ITP usually has a very sudden onset and the symptoms usually disappear in less than 6 months (often within a few weeks). It is usually a self-limiting condition and over 80% of children recover without treatment; in 5 – 10% of cases a chronic form of the disease develops.
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This question is part of the following fields:
- Haematology
- Pathology
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Question 2
Correct
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A 25-year old male is brought to the emergency room after a traffic accident. Upon examination, there was tenderness and erythema on the right acromioclavicular joint, with notable step deformity. On radiographic imaging, there is a superior elevation of the clavicle, a twice than normal coracoclavicular distance, and absence of fracture.
Which of the following structure/s is/are likely to have ruptured?Your Answer: Acromioclavicular ligament, coracoclavicular ligament and joint capsule
Explanation:Acromioclavicular joint injuries account for more than forty percent of all shoulder injuries. Mild injuries are not associated with any significant morbidity, but severe injuries can lead to significant loss of strength and function of the shoulder. Acromioclavicular injuries may be associated with a fractured clavicle, impingement syndromes, and more rarely neurovascular insults.
The AC joint is a diarthrodial joint defined by the lateral process of the clavicle articulating with the acromion process as it projects anteriorly off the scapula. The joint is primarily stabilized by the acromioclavicular ligament, which is composed of an anterior, posterior, inferior, and superior component. Of note, the superior portion of the AC ligament is the most important component for the stability of the AC joint. Supporting structures include two coracoclavicular ligaments (trapezoid and conoid ligaments), which provide vertical stability, as well as the coracoacromial ligament.
Patients with an AC joint injury typically present with anterosuperior shoulder pain and will describe a mechanism of injury of blunt trauma to the abducted shoulder or landing on an outstretched arm, suggestive of this type of injury. They may describe pain radiating to the neck or shoulder, which is often worse with movement or when they try to sleep on the affected shoulder. On examination, the clinician may observe swelling, bruising, or a deformity of the AC joint, depending on the degree of injury. The patient will be tender at that location. They may have a restriction in the active and passive range of motion secondary to pain. Piano key sign may be seen, with an elevation of the clavicle that rebounds after inferior compression.
Standard X-rays are adequate to make a diagnosis of acromioclavicular joint injury and should be used to evaluate for other causes of traumatic shoulder pain.
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This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 3
Correct
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Identify the type of graph described below:
A graph that consists of a vertical bar graph in which values are plotted in decreasing order of relative frequency from left to right. The independent variables on the chart are shown on the horizontal axis and the dependent variables are portrayed as the heights of bars.Your Answer: Pareto diagram
Explanation:A pareto diagram, or pareto chart, consists of a vertical bar graph in which values are plotted in decreasing order of relative frequency from left to right. The independent variables on the chart are shown on the horizontal axis and the dependent variables are portrayed as the heights of bars.
A point-to-point graph, which shows the cumulative relative frequency, may be superimposed on the bar.
Because the values of the statistical variables are placed in order of relative frequency, the graph clearly reveals which factors have the greatest impact and where attention is likely to yield the greatest benefit. It is extremely useful for analysing what problems need attention first, because the taller bars on the chart clearly illustrate which variable have the greatest cumulative effect on a given system.
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This question is part of the following fields:
- Evidence Based Medicine
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Question 4
Correct
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For which of the following is micelle formation necessary to facilitate intestinal absorption?
Your Answer: Vitamin D
Explanation:The arrangement of micelles is such that hydrophobic lipid molecules lie in the centre, surrounded by hydrophilic bile acids that are arranged in the outer region. This arrangement allows the entry of micelles into the aqueous layers surrounding the microvilli. As a result, the products of fat digestion (fatty acids and monoglycerides), cholesterol and fat-soluble vitamins (such as vitamin D) can then diffuse passively into the enterocytes. The bile salts are left within the lumen of the gut where they are reabsorbed from the ileum or excreted in faeces.
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This question is part of the following fields:
- Gastrointestinal
- Physiology
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Question 5
Incorrect
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A patient presents to ED complaining of pins and needles over the lateral three and a half digits. You suspect carpal tunnel syndrome. Which of the following clinical features would you most expect to see on examination:
Your Answer: Atrophy of the adductor pollicis muscle
Correct Answer: Inability to touch the pad of the little finger with the thumb
Explanation:Compression of the median nerve in the carpal tunnel will result in weakness and atrophy of the thenar muscles – resulting in weakness of opposition, abduction and flexion of the thumb at the metacarpophalangeal joint and anaesthesia or paraesthesia over the distribution of the palmar digital branch of the median nerve (skin over the palmar surface and fingertips of the lateral three and a half digits). The adductor pollicis muscle is innervated by the ulnar nerve, and abduction of the fingers is produced by the interossei, also innervated by the ulnar nerve. Flexion of the interphalangeal joint of the thumb is produced by the flexor pollicis longus, and flexion of the distal interphalangeal joint of the index finger is produced by the flexor digitorum profundus. Median nerve injury at the wrist will not affect the long flexors of the forearm as these are innervated by the anterior interosseous nerve which arises in the proximal forearm.
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This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 6
Correct
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Which of the following drug classes may cause bronchoconstriction:
Your Answer: Beta-blockers
Explanation:Beta-blockers, including those considered to be cardioselective, should usually be avoided in patients with a history of asthma, bronchospasm or a history of obstructive airways disease. However, when there is no alternative, a cardioselective beta-blocker can be given to these patients with caution and under specialist supervision. In such cases the risk of inducing bronchospasm should be appreciated and appropriate precautions taken.
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This question is part of the following fields:
- Cardiovascular
- Pharmacology
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Question 7
Correct
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A 25-year-old patient requires procedural sedation for reduction of an open fracture of his tibia and fibula. You plan on using ketamine as the sedative agent.
Ketamine works as a result of action on what type of receptor? Select ONE answer only.Your Answer: N-methyl-D-aspartate (NMDA)
Explanation:Ketamine is the only anaesthetic agent available that has analgesic, hypnotic, and amnesic properties. When used correctly it is a very useful and versatile drug.
Ketamine acts by non-competitive antagonism of the NMDA receptor Ca2+ channel pore and also inhibits NMDA receptor activity by interaction with the phencyclidine binding site.
Ketamine can be used intravenously and intramuscularly. The intramuscular dose is 10 mg/kg, and when used by this route, it acts within 2-8 minutes and has a duration of action of 10-20 minutes. The intravenous dose is 1.5-2 mg/kg administered over a period of 60 seconds. When used intravenously, it acts within 30 seconds and has a duration of action of 5-10 minutes. Ketamine is also effective when administered orally, rectally, and nasally.
Ketamine causes tachycardia, an increase in blood pressure, central venous pressure, and cardiac output, secondary to an increase in sympathetic tone. Baroreceptor function is well maintained, and arrhythmias are uncommon.
The main disadvantage to the use of ketamine is the high incidence of hallucinations, nightmares, and other transient psychotic effects. These can be reduced by the co-administration of a benzodiazepine, such as diazepam or midazolam.
The main side effects of ketamine are:
Nausea and vomiting
Hypertension
Nystagmus
Diplopia
Rash -
This question is part of the following fields:
- Anaesthesia
- Pharmacology
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Question 8
Correct
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Which of the following would you NOT expect from a deep fibular nerve palsy:
Your Answer: Loss of sensation over heel
Explanation:Damage to the deep fibular nerve results in loss of dorsiflexion of the ankle, with resultant foot drop with high-stepping gait, loss of toe extension, weakness of foot inversion and loss of sensation over the webspace between the 1st and 2nd toes.
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This question is part of the following fields:
- Anatomy
- Lower Limb
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Question 9
Incorrect
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About case-control studies, one of the following is true.
Your Answer: They provide more evidence for causal inference than a randomised controlled trial
Correct Answer: They are suitable to be used in the study of rare diseases
Explanation:Case-control studies are suitable when investigating a rare disease or in cases where little is known about the disease and the proposed aetiological factor, as a preliminary study. They have the ability to look at multiple risk-factors (exposures) but can only look at a single outcome.
In a case-control study, two groups of patients, one with the disease and one without, are compared on the basis of a proposed causative factor that occurred in the past. They are therefore a retrospective study and useful in hypothesis generation.
Cohort studies are better at identifying rare exposures. One group with an exposure is compared to a control group without that exposure.
Case-control studies are usually less expensive to run and also shorter in duration compared with prospective cohort studies.
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This question is part of the following fields:
- Evidence Based Medicine
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Question 10
Correct
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A 58-year-old woman presents with symptoms of increase in weight, proximal muscular weakening and withering, easy bruising, and acne. You notice that she has a full, plethoric aspect to her face, as well as significant supraclavicular fat pads, when you examine her. She has previously been diagnosed with Cushing's syndrome.
Which of the following biochemical profiles best supports this diagnosis?Your Answer: Hypokalaemic metabolic alkalosis
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.
A typical biochemical profile can help establish a diagnosis of Cushing’s syndrome. The following are the primary characteristics:
Hypokalaemia
Alkalosis metabolique -
This question is part of the following fields:
- Endocrine Physiology
- Physiology
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Question 11
Incorrect
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A 42-year-old woman presents with face swelling prominently affecting her upper lip and hands. She has previously been diagnosed with hereditary angioedema.
Which of these is the most appropriate management option for this acute attack?Your Answer: C1 esterase infusion
Correct Answer: Fresh frozen plasma
Explanation:Hereditary angioedema is inherited as an autosomal dominant disorder and is caused by deficiency of C1 esterase inhibitor, a protein that forms part of the complement system.
Attacks can be precipitated by stress and minor surgical procedures. Clinical features of hereditary angioedema include oedema of the skin and mucous membranes commonly affecting the face, tongue and extremities.
Angioedema and anaphylaxis due to a deficiency of C1 esterase inhibitor are resistant to adrenaline, steroids and antihistamines. Treatment is with fresh frozen plasma or C1 esterase inhibitor concentrate, which contains C1 esterase inhibitor.
Short-term prophylaxis for events that may precipitate angioedema attack is achieved with C1 esterase inhibitor or fresh frozen plasma infusions before the event while long-term prophylaxis can be achieved with antifibrinolytic drugs (tranexamic acid) or androgenic steroids.
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This question is part of the following fields:
- Pharmacology
- Respiratory Pharmacology
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Question 12
Correct
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Gastrin release from antral G-cells is stimulated by all but which one of the following:
Your Answer: Secretin
Explanation:Gastrin secretion is stimulated by:
The presence of small peptides and amino acids in chyme
Gastric distension
Vagal stimulation directly via acetylcholine and indirectly via gastrin-releasing peptide (GRP)
Raised gastric pH -
This question is part of the following fields:
- Gastrointestinal
- Physiology
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Question 13
Incorrect
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A 30-year old male is brought to the emergency room after a terrible fall during a photoshoot. The patient reported falling on his right forearm. There is evident swelling and tenderness on the affected area, with notable weakness of the flexor pollicis longus muscle. Radiographic imaging showed a fracture on the midshaft of the right radius.
Which of the following nerves is most likely injured in the case above?Your Answer: The median nerve
Correct Answer: The anterior interosseous nerve
Explanation:Flexor pollicis longus receives nervous supply from the anterior interosseous branch of median nerve, derived from spinal roots C7 and C8.
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This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 14
Correct
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A 22-year-old with a history of brittle asthma is brought to the ED by her partner. She is wheezing and very short of breath and her condition is deteriorating rapidly. Following a series of nebulisations, hydrocortisone and IV magnesium sulphate, she is taken to resus and the intensive care team is called to review her. She is severely hypoxic and confused and a decision is made to intubate her.
Which of these drugs is ideal as an induction agent in this patient?Your Answer: Ketamine
Explanation:Only about 2% of asthma attacks requires intubation and most severe cases are managed with non-invasive ventilation techniques.
Though life-saving in the crashing asthmatic, intubation in asthmatic patients is associated with significant morbidity and mortality and is risky. Indications for intubation in asthmatic patients include:
Severe hypoxia
Altered mental state
Respiratory or cardiac arrest
Failure to respond to medicationsKetamine (1-2 mg/kg) is the preferred induction agent. It has bronchodilatory properties and does not cause hypotension.
Propofol poses a risk of hypotension but can also be used.
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This question is part of the following fields:
- Pharmacology
- Respiratory Pharmacology
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Question 15
Incorrect
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Regarding transport across a membrane, which of the following statements is CORRECT:
Your Answer: Diffusion is the passive movement of molecules across a membrane from an area of low concentration to an area of high concentration.
Correct Answer: Ion channels may be voltage-gated or ligand-gated.
Explanation:Diffusion is the passive movement of ions across a cell membrane down their electrochemical or concentration gradient through ion channels. Ion channels can be voltage-gated (regulated according to the potential difference across the cell membrane) or ligand-gated (regulated by the presence of a specific signal molecule). Facilitated diffusion is the process of spontaneous passive transport of molecules or ions down their concentration gradient across a cell membrane via specific transmembrane transporter (carrier) proteins. The energy required for conformational changes in the transporter protein is provided by the concentration gradient rather than by metabolic activity. In secondary active transport there is no direct coupling of ATP but the initial Na+ electrochemical gradient that drives the secondary active transport is set up by a process that requires metabolic energy. Examples include the sodium/calcium exchanger, or the sodium/glucose symporter.
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This question is part of the following fields:
- Basic Cellular
- Physiology
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Question 16
Correct
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Which of the following diseases is caused by a build-up of lymphoblasts in the bone marrow?
Your Answer: Acute lymphoblastic leukaemia
Explanation:Acute lymphoblastic leukaemia (ALL) is a clonal (malignant) bone marrow disorder in which early lymphoid precursors multiply and replace the marrow’s normal hematopoietic cells. ALL is most common between the ages of 3 and 7, with 75 percent of cases occurring before the age of 6.
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This question is part of the following fields:
- Haematology
- Pathology
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Question 17
Correct
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Typically, granulomatous inflammation is associated with one of the following infections:
Your Answer: Tuberculosis
Explanation:Granulomatous inflammation is typically seen when an infective agent with a digestion-resistance capsule (e.g. Mycobacterium tuberculosis) or a piece of inert foreign material (such as suture or glass) is introduced into the tissue. A transient acute inflammatory response occurs and when this is ineffective in eradicating the stimulus, chronic inflammation occurs.
Tuberculosis is the prototype of the granulomatous diseases, but sarcoidosis, cat-scratch disease, lymphogranuloma inguinale, leprosy, brucellosis, syphilis, some mycotic infections, berylliosis, reactions of irritant lipids, and some autoimmune diseases are also included
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This question is part of the following fields:
- Inflammatory Responses
- Pathology
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Question 18
Correct
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A 38-year-old woman is investigated for Addison's disease. She had low blood pressure, weakness, weight loss, and skin discoloration. An adrenocorticotropic hormone (ACTH) stimulation test is scheduled as part of her treatment.
Which of the following statements about ACTH is correct?Your Answer: It is released in response to the release of CRH
Explanation:The anterior pituitary gland produces and secretes a peptide hormone called adrenocorticotropic hormone (ACTH) (adenohypophysis). It is secreted in response to the hypothalamus’s secretion of the hormone corticotropin-releasing hormone (CRH).
ACTH promotes cortisol secretion via binding to cell surface ACTH receptors in the zona fasciculata of the adrenal cortex.
ACTH also promotes the production of beta-endorphin, which is a precursor to melanocyte-releasing hormone (MRH).
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This question is part of the following fields:
- Endocrine Physiology
- Physiology
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Question 19
Correct
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A patient diagnosed with cranial nerve palsy exhibits asymmetrical movement of the palate, nasal regurgitation of food, and nasal quality to the voice.
Which of the following cranial nerves is most likely responsible for the aforementioned features?Your Answer: Vagus nerve
Explanation:The vagus nerve, ‘the wanderer’, contains motor fibres (to the palate and vocal cords), sensory components (posterior and floor of external acoustic meatus) and visceral afferent and efferent fibres.
Palatal weakness can cause nasal speech and nasal regurgitation of food. The palate moves asymmetrically when the patient says ‘ahh’. Recurrent nerve palsy results in hoarseness, loss of volume and ‘bovine cough’.
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This question is part of the following fields:
- Anatomy
- Central Nervous System
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Question 20
Correct
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A 50-year-old man has recently been on antibiotics for a chest infection. He suffers from COPD and is currently on Seretide inhalers, salbutamol, and Phyllocontin continus. Since commencing the antibiotics, he has developed nausea, vomiting and abdominal pain.
Which of the following antibiotics has he MOST LIKELY been on for his chest infection?Your Answer: Erythromycin
Explanation:Phyllocontin continues contains aminophylline, a bronchodilator used in the management of asthma and COPD.
The index patient is exhibiting symptoms of theophylline toxicity. This may have been triggered by the antibiotic he took. Macrolide antibiotics, like erythromycin and quinolone antibiotics, like ciprofloxacin and levofloxacin, increases the plasma concentration of theophyllines and can lead to toxicity.
Factors that enhance theophylline clearance include cigarette smoking, carbamazepine, phenobarbital, phenytoin, primidone, and rifampin.
Medications that inhibit clearance include ethanol, ciprofloxacin, erythromycin, verapamil, propranolol, ticlopidine, tacrine, allopurinol, and cimetidine. -
This question is part of the following fields:
- Pharmacology
- Respiratory Pharmacology
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Question 21
Correct
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A 27-year-old female is brought to the Emergency Department by ambulance with extensive bleeding from her upper arm following a fall from a bicycle onto a fence. On inspection her biceps brachii muscle has been lacerated.
How will the muscle heal from this injury? Select ONE answer only.Your Answer: Satellite cells will produce a small number of regenerated myocytes
Explanation:Muscle heals with fibrous tissue to form a scar. Once cut, it will never regain its previous bulk or power. Within the scar a small number of myocytes (muscle cells) may be seen, which are formed from satellite cells but they contribute little to the function of the muscle overall.
In more widespread ischaemic injury, such as critical ischaemic limb due to arterial compromise, or in compartment syndrome, damaged myocytes are replaced diffusely with fibrous tissue. This fibrous tissue contracts and reduces movement, and in extreme cases can pull the limb into abnormal positions such as in Volkmann’s ischaemic contracture of the forearm. -
This question is part of the following fields:
- General Pathology
- Pathology
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Question 22
Correct
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A 29 year old woman is unable to invert her foot after sustaining an injury to her leg playing water-polo. Which of the following nerves are most likely damaged:
Your Answer: Tibial and deep fibular nerve
Explanation:Inversion of the foot is primarily produced by the tibialis anterior and the tibialis posterior muscles, innervated by the deep fibular nerve and the tibial nerve respectively.
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This question is part of the following fields:
- Anatomy
- Lower Limb
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Question 23
Correct
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A 52-year old male comes to the out-patient department for a groin mass that protrudes when standing. The patient notes that it is reducible when lying down. On physical examination, there is presence of a cough impulse. The initial assessment is hernia. Further investigation reveals that the mass lies lateral to the epigastric vessels.
Among the types of hernia, which is the most likely diagnosis of the case above?Your Answer: Indirect inguinal hernia
Explanation:Inguinal hernias can present with an array of different symptoms. Most patients present with a bulge in the groin area, or pain in the groin. Some will describe the pain or bulge that gets worse with physical activity or coughing. Symptoms may include a burning or pinching sensation in the groin. These sensations can radiate into the scrotum or down the leg. It is important to perform a thorough physical and history to rule out other causes of groin pain. At times an inguinal hernia can present with severe pain or obstructive symptoms caused by incarceration or strangulation of the hernia sac contents. A proper physical exam is essential in the diagnosis of an inguinal hernia. Physical examination is the best way to diagnose a hernia. The exam is best performed with the patient standing. Visual inspection of the inguinal area is conducted first to rule out obvious bulges or asymmetry in groin or scrotum. Next, the examiner palpates over the groin and scrotum to detect the presence of a hernia. The palpation of the inguinal canal is completed last. The examiner palpates through the scrotum and towards the external inguinal ring. The patient is then instructed to cough or perform a Valsalva manoeuvre. If a hernia is present, the examiner will be able to palpate a bulge that moves in and out as the patient increases intra abdominal pressure through coughing or Valsalva.
Groin hernias are categorized into 2 main categories: inguinal and femoral.
Inguinal hernias are further subdivided into direct and indirect. An indirect hernia occurs when abdominal contents protrude through the internal inguinal ring and into the inguinal canal. This occurs lateral to the inferior epigastric vessels. The hernia contents may extend into the scrotum, and can be reduced superiorly then superolaterally. A direct inguinal hernia is protrusion of abdominal contents through the transversalis fascia within Hesselbach’s triangle. The borders of Hesselbach’s triangle are the inferior epigastric vessels superolaterally, the rectus sheath medially, and inguinal ligament inferiorly.
A femoral hernia is a protrusion into the femoral ring. The borders of the femoral ring are the femoral vein laterally, Cooper’s ligament posteriorly, the iliopubic tract/inguinal ligament anteriorly and lacunar ligament medially.
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This question is part of the following fields:
- Abdomen And Pelvis
- Anatomy
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Question 24
Correct
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You are giving a teaching session to a group of final year medical students regarding lower limb neurology. Which of the following clinical features would be expected in an obturator nerve palsy:
Your Answer: Weakness of hip adduction
Explanation:Damage to the obturator nerve results in weak adduction of the hip with lateral swinging of the limb during walking due to unopposed abduction.
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This question is part of the following fields:
- Anatomy
- Lower Limb
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Question 25
Correct
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A 44-year-old man with an acute episode of gout presents to you and you discuss treatment plan with him.
Which one of these statements concerning the treatment of acute gout is true?Your Answer: A common first-line treatment is Naproxen as a stat dose of 750 mg followed by 250 mg TDS
Explanation:High-dose NSAIDs are the first-line treatment for acute gout. In the absence of any contraindications, Naproxen 750 mg as a stat dose followed by 250 mg TDS is commonly used.
Aspirin is contraindicated in gout. It reduces the urinary clearance of urate and also interferes with the action of uricosuric agents.
Colchicine is preferred in patients with heart failure or in those who are intolerant of NSAIDs. It is as effective as NSAIDs in relieving acute attacks.
Colchicine acts on the neutrophils, binding to tubulin to prevent neutrophil migration into the joint. Where Allopurinol is not tolerated, it has a role in prophylactic treatment of gout.
Allopurinol should not be started in the acute phase of gout as it increases the severity and duration of symptoms. It is used as a prophylaxis in preventing future attacks and acts by reducing serum uric acid levels.
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This question is part of the following fields:
- Musculoskeletal Pharmacology
- Pharmacology
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Question 26
Correct
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Flumazenil is a reversal agent for which of the following groups of drugs:
Your Answer: Benzodiazepines
Explanation:Flumazenil is a benzodiazepine antagonist used for the reversal of the sedative effects of benzodiazepines after anaesthesia, sedation and similar procedures.
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This question is part of the following fields:
- Anaesthesia
- Pharmacology
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Question 27
Incorrect
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A 35-year-old lady has suffered a serious brain injury. Her uvula has deviated to the right, according to inspection. Which of the following nerves is likely to be affected?
Your Answer: Left glossopharyngeal nerve
Correct Answer: Left vagus nerve
Explanation:When the vagus nerve is damaged, the soft palate is paralyzed and the uvula is shifted away from the affected side. The vagus nerve innervates the uvulae muscle, which forms the uvula’s core. If only one side is innervated, contraction of the active muscle will draw the uvula towards it.
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This question is part of the following fields:
- Anatomy
- Cranial Nerve Lesions
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Question 28
Correct
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All of the following cause bronchoconstriction, EXCEPT for:
Your Answer: Adrenaline
Explanation:Factors causing bronchoconstriction:
- Via muscarinic receptors
- Parasympathetic stimulation
- Stimulation of irritant receptors
- Inflammatory mediators e.g. histamine, prostaglandins, leukotrienes
- Beta-blockers
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This question is part of the following fields:
- Physiology
- Respiratory
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Question 29
Correct
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A patient sustains an injury to the proximal median nerve after falling through a glass door. Which of the following muscles would you not expect to be affected:
Your Answer: Flexor carpi ulnaris
Explanation:All of the muscles in the anterior forearm are innervated by the median nerve, except for the flexor carpi ulnaris and the medial half of the flexor digitorum profundus which are innervated by the ulnar nerve.
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This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 30
Correct
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A patient has a cardiac output of 4.8 L/min and a heart rate of 80 bpm, therefore their stroke volume is:
Your Answer: 60 mL
Explanation:Cardiac output (CO) = Stroke volume (SV) x Heart rate (HR).
Therefore SV = CO/HR
= 4.8/80
= 0.06 L = 60 mL. -
This question is part of the following fields:
- Cardiovascular
- Physiology
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Question 31
Incorrect
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A newborn baby is referred by the community midwife who is concerned the baby is jaundiced because of the yellow appearance of his eyes and skin following a postnatal home visit. The jaundice is visible in the baby’s feet making her worried.
Jaundice are visible in the extremities of neonates at what approximate threshold bilirubin level?Your Answer: 100 μmol/L
Correct Answer: 255 μmol/L
Explanation:Newborn babies have a higher concentration of red blood cells with shorter lifespan leading to higher bilirubin levels than in adults. This condition is short-lived and harmless but with potential serious causes that need to be assessed for if present.
The most obvious physical sign of jaundice is a yellow discolouration of the sclera, skin and mucous membranes. At a bilirubin level of 35 μmol/L or higher, the eye is affected. The bilirubin level will need to be higher than 255 μmol/L for the feet and extremities to be affected.
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This question is part of the following fields:
- General Pathology
- Pathology
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Question 32
Correct
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Which of the following is the most common cause of megaloblastic anaemia:
Your Answer: Vitamin B12 deficiency
Explanation:Megaloblastic anemia results from inhibition of DNA synthesis during red blood cell production. When DNA synthesis is impaired, the cell cycle cannot progress from the growth stage to the mitosis stage. This leads to continuing cell growth without division, which presents as macrocytosis, with an increase in mean corpuscular volume (MCV). The defect in red cell DNA synthesis is most often due to hypovitaminosis, specifically vitamin B12 deficiency or folate deficiency.
Folate is an essential vitamin found in most foods, especially liver, green vegetables and yeast. The normal daily diet contains 200 – 250 μg, of which about 50% is absorbed. Daily adult requirements are about 100 μg. Absorption of folate is principally from the duodenum and jejunum. Stores of folate are normally only adequate for 4 months and so features of deficiency may be apparent after this time. -
This question is part of the following fields:
- Haematology
- Pathology
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Question 33
Correct
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A patient presents with a history of renal problems, generalised weakness and palpitations. Her serum potassium levels are measured and come back at 6.2 mmol/L. An ECG is performed, and it shows some changes that are consistent with hyperkalaemia.
Which of the following ECG changes is usually the earliest sign of hyperkalaemia? Select ONE answer only.Your Answer: Peaked T waves
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 abnormalities
K+>6.5 mmol/l – P waves widen and flatten, PR segment lengthens, P waves eventually disappear
K+>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. -
This question is part of the following fields:
- Physiology
- Renal Physiology
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Question 34
Correct
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A 17-year-old type I diabetic patient presents with abdominal pain and vomiting. Measurement of her blood glucose level is done and found to be grossly elevated. She is diagnosed with diabetic ketoacidosis. A fixed rate insulin infusion is given as part of her treatment.
Which of these is an action of insulin?Your Answer: Stimulates lipogenesis
Explanation:Insulin is an anabolic hormone. Its actions can be broadly divided into:
Lipid metabolism
Protein metabolism and
Carbohydrate metabolismFor lipid metabolism, insulin:
Stimulates lipogenesis
Inhibits lipolysis by lipaseFor carbohydrate metabolism, insulin:
Decreases gluconeogenesis
Stimulates glycolysis
Promotes glucose uptake in muscle and adipose tissue
Promotes glycogen storage
Increases glycogenesis
Decreases glycogenolysisProtein metabolism:
Stimulates protein synthesis
Accelerates net formation of protein
Stimulates amino acid uptake
Inhibits protein degradation
Inhibits amino acid conversion to glucose -
This question is part of the following fields:
- Endocrine Physiology
- Physiology
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Question 35
Correct
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A 62-year-old woman has reduced urine output, nausea, and confusion. Renal function tests and other investigations done leads to a diagnosis of acute kidney injury (AKI). Which one of these is consistent with a diagnosis of AKI?
Your Answer: A rise in serum creatinine of 26 μmol/L within 48 hours
Explanation:AKI is diagnosed based on an acutely rising serum creatinine and/or reduction in urine output.
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AKI can often be non-oliguric.
AKI is present if any one or more of the following criteria is met:
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A rise in serum creatinine of ≥26 micromol/L (≥0.3 mg/dL) within 48 hours
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A rise in serum creatinine to ≥1.5 times baseline, which is known or presumed to have occurred within the past 7 days (in practice you can use the lowest value from the past 3 months as the baseline for the patient)
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Urine volume <0.5 ml/kg/hour for at least 6 hours.
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This question is part of the following fields:
- General Pathology
- Pathology
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Question 36
Correct
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Following a phone call from the microbiology consultant, you evaluate a patient who has been diagnosed with urinary sepsis. Following the results of the blood cultures, he recommends that you add gentamicin to the patient's antibiotic treatment.
Gentamicin produces its pharmacological effect by binding to which of the following?Your Answer: The 30S subunit of the bacterial ribosome
Explanation:Antibiotics with aminoglycosides, such as gentamicin, bind to the 30S subunit of the bacterial ribosome and prevent aminoacyl-tRNA from binding, preventing protein synthesis.
They also cause mRNA misreading, resulting in the production of non-functional proteins. This last mechanism is unique to aminoglycosides, and it may explain why they are bactericidal rather than bacteriostatic, as other protein synthesis inhibitors are.
Patients with myasthenia gravis should avoid aminoglycosides since they can disrupt neuromuscular transmission. They cross the placenta and are linked to poisoning of the 8th cranial nerve in the foetus, as well as permanent bilateral deafness.
It is possible that they will cause deafness, although this is not a contraindication. In individuals with renal impairment, serum aminoglycoside concentrations should be closely monitored, but this is still not considered a contraindication.
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This question is part of the following fields:
- Infections
- Pharmacology
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Question 37
Correct
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A patient suffers a stab wound to the neck. The entry point of the blade is situated within the anterior triangle of the neck.
Which of the following muscles is most likely to be involved? Select ONE answer only.Your Answer: Sternohyoid
Explanation:The anterior triangle is the triangular area of the neck found anteriorly to the sternocleidomastoid muscle. It is formed by the anterior border of sternocleidomastoid laterally, the median line of the neck medially and by the inferior border of the mandible superiorly. The apex of the anterior triangle extends towards the manubrium sterni. The anterior triangle contains:
Muscles: thyrohyoid, sternothyroid, sternohyoid muscles
Organs: thyroid gland, parathyroid glands, larynx, trachea, esophagus, submandibular gland, caudal part of the parotid gland
Arteries: superior and inferior thyroid, common carotid, external carotid, internal carotid artery (and sinus), facial, submental, lingual arteries
Veins: anterior jugular veins, internal jugular, common facial, lingual, superior thyroid, middle thyroid veins, facial vein, submental vein, lingual veins
Nerves: vagus nerve (CN X), hypoglossal nerve (CN XII), part of sympathetic trunk, mylohyoid nerveThe posterior triangle is a triangular area found posteriorly to the sternocleidomastoid muscle. It has three borders; anterior, posterior and inferior borders. The anterior border is the posterior margin of the sternocleidomastoid muscle. The posterior border is the anterior margin of the trapezius muscle, while the inferior border is the middle one-third of the clavicle. The investing layer of deep cervical fascia and integument forms the roof of the space, while the floor is covered with the prevertebral fascia along with levator scapulae, splenius capitis and the scalene muscles. The inferior belly of omohyoid subdivides the posterior triangle into a small supraclavicular, and a large occipital, triangle.
Contents:
Vessels: the third part of the subclavian artery, suprascapular and transverse cervical branches of the thyrocervical trunk, external jugular vein, lymph nodes
Nerves: accessory nerve (CN XI), the trunks of the brachial plexus, fibers of the cervical plexus -
This question is part of the following fields:
- Anatomy
- Head And Neck
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Question 38
Incorrect
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Cardiac myocytes contract by excitation-contraction coupling, very much like skeletal myocytes. On the other hand, calcium-induced calcium release (CICR) is a mechanism that is unique to Cardiac myocytes. The influx of calcium ions (Ca 2+) into the cell causes a 'calcium spark,' which causes more ions to be released into the cytoplasm.
In CICR, which membrane protein in the sarcoplasmic reticulum is involved?Your Answer: Ligand-gated calcium channel
Correct Answer: Ryanodine receptor
Explanation:Cardiac myocytes contract by excitation-contraction coupling, just like skeletal myocytes. Heart myocytes, on the other hand, utilise a calcium-induced calcium release mechanism that is unique to cardiac muscle (CICR). The influx of calcium ions (Ca2+) into the cell causes a ‘calcium spark,’ which causes more ions to be released into the cytoplasm.
An influx of sodium ions induces an initial depolarisation, much as it does in skeletal muscle; however, in cardiac muscle, the inflow of Ca2+ sustains the depolarisation, allowing it to remain longer. Due to potassium ion (K+) inflow, CICR causes a plateau phase in which the cells remain depolarized for a short time before repolarizing. Skeletal muscle, on the other hand, repolarizes almost instantly.
The release of Ca2+ from the sarcoplasmic reticulum is required for calcium-induced calcium release (CICR). This is mostly accomplished by ryanodine receptors (RyR) on the sarcoplasmic reticulum membrane; Ca2+ binds to RyR, causing additional Ca2+ to be released.
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This question is part of the following fields:
- Basic Cellular Physiology
- Physiology
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Question 39
Correct
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Regarding nitrous oxide, which of the following statements is CORRECT:
Your Answer: Nitrous oxide may be used for maintenance of anaesthesia where its use allows reduced dosage of other agents.
Explanation:For anaesthesia, nitrous oxide is commonly used in a concentration of around 50 – 66% in oxygen in association with other inhalation or intravenous agents. Nitrous oxide cannot be used as the sole anaesthetic agent due to lack of potency, but is useful as part of a combination of drugs since it allows reduction in dosage of other agents. Exposure to nitrous oxide for prolonged periods, either by continuous or by intermittent administration, may result in megaloblastic anaemia as a result of interference with the action of vitamin B12. Nitrous oxide increases cerebral blood flow and should be avoided in patients with, or at risk of, raised intracranial pressure. Nitrous oxide may be administered by any trained personnel experienced in its use.
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This question is part of the following fields:
- Anaesthesia
- Pharmacology
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Question 40
Correct
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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: 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 41
Incorrect
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A 30 year old man presents to ED after a road traffic accident. Free intraperitoneal fluid is found on FAST (Focussed assessment for sonography in trauma) done in the supine position.
Which of these is most likely to be affected?
Your Answer: Subphrenic recess
Correct Answer: Hepatorenal recess
Explanation:Fluid accumulates most often in the hepatorenal pouch (of Morrison) in a supine patient. The hepatorenal pouch is located behind the liver and anterior to the right kidney and is the lowest space in the peritoneal cavity in the supine position.
Although the vesicouterine and rectouterine spaces are also potential spaces for fluid accumulation, fluid accumulation in them occur in the erect position.
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This question is part of the following fields:
- Abdomen
- Anatomy
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Question 42
Correct
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A 50-year-old man managed by the renal team for stage 4 chronic kidney disease which appears to be deteriorating presents with a history of shortness of breath and ankle oedema. His most recent blood tests shows low calcium levels.
Which of these increases the renal reabsorption of calcium?Your Answer: Parathyroid hormone
Explanation:Parathyroid hormone (PTH), a polypeptide containing 84 amino acids, is the principal hormone that controls free calcium in the body.
Its main actions are:
Increases osteoclastic activity
Increases plasma calcium concentration
Decreases renal phosphate reabsorption
Decreases plasma phosphate concentration
Increases renal tubular reabsorption of calcium
Increases calcium and phosphate absorption in the small intestine
Increases renal conversion of 25-hydroxycholecalciferol to 1,25-dihydroxycholecalciferol -
This question is part of the following fields:
- Endocrine Physiology
- Physiology
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Question 43
Correct
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Which of the following is NOT an adverse effect associated with statin therapy:
Your Answer: Aplastic anaemia
Explanation:Adverse effects of statins include:, Headache, Epistaxis, Gastrointestinal disorders (such as constipation, flatulence, dyspepsia, nausea, and diarrhoea), Musculoskeletal and connective tissue disorders (such as myalgia, arthralgia, pain in the extremity, muscle spasms, joint swelling, and back pain), Hyperglycaemia and diabetes, Myopathy and rhabdomyolysis, Interstitial lung disease and Hepatotoxicity
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This question is part of the following fields:
- Cardiovascular
- Pharmacology
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Question 44
Correct
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A 32-year-old asthmatic patient on theophylline as part of her asthma management presents to the Emergency Department with an unrelated medical condition.
Which of these drugs should be avoided?Your Answer: Clarithromycin
Explanation:Macrolide antibiotics (e.g. clarithromycin and erythromycin) are cytochrome P450 enzyme inhibitors. They increase blood levels of theophylline leading to hypokalaemia, and potentially increasing the risk of Torsades de pointes when they are prescribed together.
Co-prescription with theophylline should be avoided.
Factors that enhance theophylline clearance include cigarette smoking, carbamazepine, phenobarbital, phenytoin, primidone, and rifampin.
Medications that inhibit clearance include ethanol, ciprofloxacin, erythromycin, verapamil, propranolol, ticlopidine, tacrine, allopurinol, and cimetidine. -
This question is part of the following fields:
- Pharmacology
- Respiratory Pharmacology
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Question 45
Correct
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You examine a resuscitated patient who has been diagnosed with ventricular tachycardia. The patient's hemodynamics are normal. You intended to prescribe amiodarone to him, but you can't because he has a contraindication.
In these circumstances, which of the following is a contraindication to using amiodarone?Your Answer: Sinus node disease
Explanation:Amiodarone is an anti-arrhythmic medication that can be used to treat both ventricular and atrial arrhythmias.
The use of amiodarone is contraindicated in the following situations:
Conduction disturbances that are severe (unless pacemaker fitted)
Sinus node disease is a condition that affects the lymph nodes in (unless pacemaker fitted)
Sensitivity to iodine
Blockage of the Sino-atrial heart valve (except in cardiac arrest)
Bradycardia in the sinuses (except in cardiac arrest)
Thyroid disorders -
This question is part of the following fields:
- Cardiovascular Pharmacology
- Pharmacology
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Question 46
Incorrect
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You suspected typhoid disease in a patient who had recently returned from South America and presented to the emergency department with fever, constipation, and a rose spot rash. Which of the following antibiotics will be administered to this patient?
Your Answer: Metronidazole
Correct Answer: Cefotaxime
Explanation:Typhoid fever, often known as enteric fever, is a potentially fatal multi-systemic sickness caused predominantly by Salmonella enterica serotype typhi and, to a lesser extent, paratyphi A, B, and C.
Cefotaxime is the first-line treatment for typhoid fever (or ceftriaxone). In cases of mild or moderate sickness caused by multiresistant pathogens, azithromycin is an option. If the bacterium is sensitive, ciprofloxacin is an option.
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This question is part of the following fields:
- Microbiology
- Pathogens
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Question 47
Correct
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In a ward round, you come across a patient's treatment chart prescribed an antibiotic to fight his infection. This antibiotic is a protein synthesis inhibitor.
Which of the following antimicrobial drugs is prescribed to this patient?Your Answer: Gentamicin
Explanation:Gentamicin, an aminoglycoside antibiotic, acts by binding to the 30S subunit of the bacterial ribosome inhibiting the binding of aminoacyl-tRNA and thus preventing initiation of protein synthesis.
Vancomycin inhibits cell wall peptidoglycan formation by binding the D-Ala-D-Ala portion of cell wall precursors.
Penicillins and cephalosporins are the major antibiotics that inhibit bacterial cell wall synthesis. They inactivate transpeptidases that help cross-link peptidoglycans in cell walls.
Metronidazole and the other 5-nitroimidazole agents inhibit nucleic acid synthesis by forming toxic free radical metabolites in the bacterial cell that damage DNA.
Ciprofloxacin inhibits prokaryotic enzymes topoisomerase II (DNA gyrase) and topoisomerase IV.
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This question is part of the following fields:
- Infections
- Pharmacology
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Question 48
Correct
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What is nimodipine used predominantly in the treatment of?
Your 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 49
Correct
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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: 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 50
Correct
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You're evaluating a male patient who's having a lung function test done. In calculating the patient’s functional residual capacity, what parameters should you add to derive the functional residual capacity volume?
Your Answer: Expiratory reserve volume + residual volume
Explanation:The volume of air that remains in the lungs after a single breath is known as functional residual capacity (FRC). It is calculated by combining the expiratory reserve volume and residual volume.
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This question is part of the following fields:
- Physiology
- Respiratory Physiology
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Question 51
Incorrect
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A blood transfusion is given to a 52-year-old woman. She develops chills and rigours shortly after the transfusion begins.
The following are her observations: Temperature 40°C, HR 116 bpm, BP 80/48, SaO 2 97 percent on air.
Which of the following treatments is the most appropriate?Your Answer: Stop the transfusion and administer corticosteroids
Correct Answer: Stop the transfusion and administer antibiotics
Explanation:Bacterial infections are common in the following situations:
Platelet transfusions are associated with a higher risk of bacterial infection (as platelets are stored at room temperature)
Immersion in a water bath thawed previously frozen components.
Components of red blood cells that have been stored for several weeks
Gram-positive and Gram-negative bacteria have both been linked to transfusion-transmitted bacterial infection, but Gram-negative bacteria are linked to a higher rate of morbidity and mortality.
Yersinia enterocolitica is the most common bacterial organism linked to transfusion-transmitted bacterial infection. This organism can multiply at low temperatures while also utilising iron as a nutrient. As a result, it’s well-suited to proliferating in blood banks.The following are some of the most common clinical signs and symptoms of a bacterial infection transmitted through a blood transfusion. These symptoms usually appear shortly after the transfusion begins:
Fever is very high.
Rigours and chills
Vomiting and nausea
Tachycardia
Hypotension
Collapse of the circulatory systemIf a bacterial infection from a transfusion is suspected, the transfusion should be stopped right away. Blood cultures and a Gram stain should be requested, as well as broad-spectrum antibiotics. In addition, the blood pack should be returned to the blood bank for an urgent culture and Gram-stain.
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This question is part of the following fields:
- Haematology
- Pathology
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Question 52
Correct
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You are calculating the anion gap on a patient with an acid-base disturbance and you find the anion gap to be low. Which of the following is the most likely cause for the low anion gap:
Your Answer: Hypoalbuminaemia
Explanation:A low anion gap is frequently caused by hypoalbuminemia. Albumin is a negatively charged protein and its loss from the serum results in the retention of other negatively charged ions such as chloride and bicarbonate. As bicarbonate and chloride anions are used to calculate the anion gap, there is a subsequent decrease in the gap. The anion gap is sometimes reduced in multiple myeloma, where there is an increase in plasma IgG (paraproteinaemia).
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This question is part of the following fields:
- Physiology
- Renal
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Question 53
Incorrect
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Which of these statements about experimental studies is true?
Your Answer: Examples include cohort studies
Correct Answer: Randomisation serves to remove potential bias
Explanation:In experimental studies, the researcher introduces an intervention and studies the effect. The study subjects are allocated into different groups by the investigator through the use of randomisation. Randomisation serves to remove any potential bias.
A cohort study is a form of longitudinal, observational study that follows a group of patients (the cohort) over a period of time to monitor the effects of exposure to a proposed aetiological factor upon them.
A case-control study is a type observational study. Here, patients who have developed a disease are identified and compared on the basis of proposed causative factors that occurred in the past, to a control group.
Clinical trials are experimental studies. Examples include: double blind, single blind, and unblinded studies(both patient and researcher are aware of the treatment they receive)
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This question is part of the following fields:
- Evidence Based Medicine
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Question 54
Correct
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A 54-year-old woman has been visiting her GP with symptoms of tiredness, muscle weakness and headaches. She is known to be hypertensive and takes amlodipine to control this. Her blood results today show that her potassium level is low at 3.0 mmol/L, and her sodium level is slightly elevated at 146 mmol/L.
Which of the following is the SINGLE most appropriate INITIAL investigation?Your Answer: Plasma renin and aldosterone levels
Explanation:Primary hyperaldosteronism occurs when there are excessive levels of aldosterone independent of the renin-angiotensin axis. Secondary hyperaldosteronism occurs due to high renin levels.
The causes of primary hyperaldosteronism include:
Adrenal adenoma (Conn’s syndrome) – the most common cause of hyperaldosteronism (,80% of all cases). These are usually unilateral and solitary and are more common in women.
Adrenal hyperplasia – this accounts for ,15% of all cases. Usually, bilateral adrenal hyperplasia (BAH) but can be unilateral rarely. More common in men than women.
Adrenal cancer – a rare diagnosis but essential not to miss
Familial aldosteronism – a rare group of inherited conditions affecting the adrenal glands
The causes of secondary hyperaldosteronism include:
Drugs – diuretics
Obstructive renal artery disease – renal artery stenosis and atheroma
Renal vasoconstriction – occurs in accelerated hypertension
Oedematous disorders – heart failure, cirrhosis and nephrotic syndrome
Patients are often asymptomatic. When clinical features are present, the classically described presentation of hyperaldosteronism is with:
Hypertension
Hypokalaemia
Metabolic alkalosis
Sodium levels can be normal or slightly raised
Other, less common, clinical features include:
Lethargy
Headaches
Muscle weakness (from persistent hypokalaemia)
Polyuria and polydipsia
Intermittent paraesthesia
Tetany and paralysis (rare)
Often the earliest sign of hyperaldosteronism is from aberrant urea and electrolytes showing hypokalaemia and mild hypernatraemia. If the patient is taking diuretics, and the diagnosis is suspected, these should be repeated after the patient has taken off diuretics.
If the diagnosis is suspected, plasma renin and aldosterone levels should be checked. Low renin and high aldosterone levels (with a raised aldosterone: renin ratio) is suggestive of primary aldosteronism.
If the renin: aldosterone ratio is high, then the effect of posture on renin, aldosterone and cortisol can be investigated to provide further information about the underlying cause of primary hyperaldosteronism. Levels should be measured lying at 9 am and standing at noon:
If aldosterone and cortisol levels fall on standing, this is suggestive of an ACTH dependent cause, e.g. adrenal adenoma (Conn’s syndrome)
If aldosterone levels rise and cortisol levels fall on standing, this is suggestive of an angiotensin-II dependent cause, e.g. BAH
Other investigations that can help to distinguish between an adrenal adenoma and adrenal hyperplasia include:
CT scan
MRI scan
Selective adrenal venous sampling -
This question is part of the following fields:
- Endocrine Physiology
- Physiology
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Question 55
Incorrect
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Which of the following statements accurately describes the number needed to harm?
Your Answer: The NNH can be used to calculate the negative predictive value of a test
Correct Answer: The NNH is the number of patients that need to be treated for one to experience the side effect
Explanation:Number needed to harm (NNH) corresponds to the number of individuals that must be treated, so that one of them presents an adverse reaction accountable to the treatment.
Hence, a NNH of 100 means that 100 individuals need to be treated in order to produce an adverse effect of the treatment in one individual.
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This question is part of the following fields:
- Evidence Based Medicine
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Question 56
Correct
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A 30-year-old woman presents with a history of fever and sore throat. On examination, there is tonsillar exudate and cervical lymphadenopathy and a diagnosis of tonsillitis is made. A course of penicillin is prescribed.
What is the mechanism of action of penicillin?
Your Answer: Inhibition of cell wall synthesis
Explanation:Penicillin is bactericidal and produces its antimicrobial action by preventing cross-linkage between the linear peptidoglycan polymer chains that make up the bacterial cell wall. This action inhibits cell wall synthesis.
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This question is part of the following fields:
- Infections
- Pharmacology
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Question 57
Correct
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Streptococcus pyogenes is commonly implicated in all of the following infective diseases EXCEPTÂ for:
Your Answer: Gas gangrene
Explanation:Gas gangrene is a life-threatening infection caused by toxin-producing Clostridium species, primarily Clostridium perfringens, and characterised by rapidly progressive muscle necrosis, gas production and sepsis.
Gas gangrene is not a notifiable disease. -
This question is part of the following fields:
- Microbiology
- Pathogens
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Question 58
Correct
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Which of the following drugs decreases plasma-theophylline levels:
Your 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 59
Correct
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A 62-year-old man complains of chest pain and goes to the emergency room. You diagnose him with an acute coronary syndrome and prescribe enoxaparin as part of his treatment plan.
Enoxaparin inactivates which of the following?Your Answer: Thrombin
Explanation:Enoxaparin is a low molecular weight heparin (LMWH) that works in the same way as heparin by binding to and activating the enzyme inhibitor antithrombin III. Antithrombin III inactivates thrombin by forming a 1:1 complex with it. Factor Xa and a few other clotting proteases are also inhibited by the heparin-antithrombin III complex.
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This question is part of the following fields:
- Cardiovascular Pharmacology
- Pharmacology
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Question 60
Correct
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A 7-year-old girl is admitted to the hospital with a persistently high temperature. To help her reduce her fever, you decide to give her paracetamol and ibuprofen.
What are the effects of paracetamol and ibuprofen on fever?Your Answer: Reduction in prostaglandin synthesis
Explanation:Interleukin-1, which is released by leukocytes and acts on the thermoregulatory centre of the hypothalamus, causes fever. Because prostaglandins mediate this process, antipyretics such as NSAIDs, paracetamol, and aspirin reduce prostaglandin levels by inhibiting cyclooxygenase enzymes. Malignant disease secretes interleukins, which cause the B-symptoms seen in lymphoma, for example. Bacterial toxins can also cause interleukins to be produced.
Pyrexia of unknown origin (PUO) is defined as a fever of greater than 38.3 degrees Celsius that lasts for more than 2-3 weeks with no clear diagnosis despite extensive investigation.
Investigation necessitates a thorough understanding of the conditions that can cause febrile illness, which may be missed during an initial investigation, as well as a thorough history, examination, and investigation centred on that list.
Pyrexia of unknown origin has a wide differential diagnosis, which includes:
Infection
Bacterial
Pyogenic abscess
Tuberculosis
Infective endocarditis
Brucellosis
Lyme disease
Viral
HIV
Epstein Barr Virus
Cytomegalovirus
Parasite
Toxoplasmosis
Malignancy
Leukaemia
Lymphoma
Renal cell carcinoma
Hepatocellular carcinoma
Vasculitides
Still’s disease
Granulomatosis with polyangiitis (formerly Wegener’s)
Systemic lupus erythematosus
Giant cell arteritis
Rheumatoid arthritis
Polymyalgia rheumatica
Miscellaneous
Drug induced fevers
Familial Mediterranean fever
Thyrotoxicosis
Inflammatory bowel disease
Sarcoidosis
Factitious fever
Exaggerated normal circadian fluctuationThe patient might need to be admitted to the hospital for observation and further investigation. Because infection is still a possibility, blood cultures should be repeated on a regular basis, and inflammatory markers should be closely monitored. CT, PET, and MRI imaging have largely replaced diagnostic laparotomy as a diagnostic tool.
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This question is part of the following fields:
- Pathology
- Pathology Of Infections
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Question 61
Correct
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A 34-year-old male presents to the Emergency Department with the complaint of palpitations and difficulty breathing, which started suddenly half an hour ago. His ECG shows findings of supraventricular tachycardia. You attempt vagal manoeuvres but cannot convert them back to sinus rhythm. Therefore, drug therapy is necessary to terminate the arrhythmia. Adenosine cannot be used in this patient because of a contra-indication listed in his medical record.
Which one of the conditions listed below would be a contraindication in this case?Your Answer: Asthma
Explanation:Entonox is a mixture of 50% Oxygen and 50% nitrous oxide and is given in an inhaled form as a quick form of analgesia. Entonox causes non-competitive inhibition of NMDA (N-methyl-D-aspartate) receptors, which are a subtype of the glutamate receptor.
It is stored in blue and white cylinders and administered via a pressure regulator and demand valve. The administration of this medicine reduces pain and anxiety in paediatric and dental procedures ands during labour.
Effects are apparent after 20 seconds, and peak action occurs after 3 to 5 minutes as it is a drug with a rapid onset and the patient will also recover rapidly from its effects. Entonox is widely used as it does not accumulate in the body and does not cause many side effects. However, a notable side effect is the inhibition of Vitamin B12 synthesis.
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This question is part of the following fields:
- Cardiovascular Pharmacology
- Pharmacology
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Question 62
Correct
-
As a result of a cardiovascular drug she was prescribed, a 67-year-old woman develops corneal microdeposits.
Which of the following drugs is the MOST LIKELY cause?Your Answer: Amiodarone
Explanation:Corneal microdeposits are almost universally present (over 90%) in people who have been taking amiodarone for more than six months, especially at doses above 400 mg/day. Although these deposits usually cause no symptoms, about 10% of patients report seeing a ‘bluish halo.’ This goes away once the treatment is stopped, and it rarely causes vision problems.
Other effects of amiodarone on the eye are much rarer, occurring in only 1-2 percent of patients:
Optic neuropathy is a condition that affects the eyes.
Non-arteritic anterior ischaemic optic neuropathy (N-AION)
Swelling of the optic disc -
This question is part of the following fields:
- Cardiovascular Pharmacology
- Pharmacology
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Question 63
Correct
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Which of the following data types does a pain-scoring system represent?
Your Answer: Ordinal
Explanation:Pain scoring systems are processes for assessing pain and the severity of illnesses that have been scientifically designed and tested. An example of ordinal categorical data is a pain scoring system.
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This question is part of the following fields:
- Evidence Based Medicine
- Statistics
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Question 64
Incorrect
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A 31-year-old man with sickle-cell disease receives a blood transfusion for symptomatic anaemia. He presents to the Emergency Department three weeks later with a rash, fever, and diarrhoea. He has pancytopenia and abnormal liver function results on blood tests.
Which of the transfusion reactions is most likely to have happened?Your Answer: Delayed haemolytic reaction
Correct Answer: Graft-vs-host disease
Explanation:Blood transfusion can be a life-saving treatment with significant clinical benefits, but it also comes with a number of risks and potential complications, including:
Immunological side effects
Errors in administration (episodes of ‘wrong blood’)
Viruses and Infections (bacterial, viral, possibly prion)
ImmunodilutionA culture of better safety procedures as well as steps to reduce the use of transfusion has emerged as a result of growing awareness of avoidable risk and improved reporting systems. Transfusion errors, on the other hand, continue to occur, and some serious adverse reactions go unreported.
Transfusion-associated graft-vs-host disease (TA-GVHD) is a rare blood transfusion complication that causes fever, rash, and diarrhoea 1-4 weeks after the transfusion. Pancytopenia and liver function abnormalities are common laboratory findings.
TA-GVHD, unlike GVHD following allogeneic marrow transplantation, causes profound marrow aplasia with a mortality rate of >90%. Survival is uncommon, with death occurring within 1-3 weeks of the onset of symptoms.
Because of immunodeficiency, severe immunosuppression, or shared HLA antigens, viable T lymphocytes in blood components are transfused, engraft, and react against the recipient’s tissues, and the recipient is unable to reject the donor lymphocytes.
The following is a list of the most common transfusion reactions and complications:1) Reaction to a febrile transfusion
The temperature rises by one degree from the baseline. Chills and malaise are also possible symptoms.
The most common response (1 in 8 transfusions).
Cytokines from leukocytes in transfused red cell or platelet components are usually to blame.
Only supportive. The use of paracetamol is beneficial.2) Acute haemolytic reaction is a type of haemolytic reaction that occurs when the
Fever, chills, pain at the transfusion site, nausea, vomiting, and dark urine are all symptoms of a transfusion reaction.
Early on, many people report a sense of ‘impending doom.’
The most serious reaction. ABO incompatibility is frequently caused by a clerical error.
STOP THE TRANSFUSION OF INFORMATION. IV fluids should be given. It’s possible that diuretics will be required.3) Haemolytic reaction that is delayed
It usually happens 4 to 8 days after a blood transfusion.
Fever, anaemia, jaundice, and haemoglobinuria are all symptoms that the patient has.
Positive Coombs test for direct antiglobulin.
Because of the low titre antibody, it is difficult to detect in a cross-match, and it is unable to cause lysis at the time of transfusion.
The majority of delayed haemolytic reactions are harmless and do not require treatment.
Anaemia and renal function should be monitored and treated as needed.4) Reaction to allergens
Foreign plasma proteins are usually to blame, but anti-IgA could also be to blame.
Urticaria, pruritus, and hives are typical allergic reactions. It’s possible that it’s linked to laryngeal oedema or bronchospasm.
Anaphylaxis is a rare occurrence.
Antihistamines can be used to treat allergic reactions symptomatically. It is not necessary to stop transfusions.
If the patient develops anaphylaxis, the transfusion should be stopped and the patient should be given adrenaline and treated according to the ALS protocol.5) TRALI (Transfusion Related Acute Lung Injury)
Within 6 hours of transfusion, there was a sudden onset of non-cardiogenic pulmonary oedema.
It’s linked to the presence of antibodies to recipient leukocyte antigens in the donor blood.
The most common cause of death from transfusion reactions is this.
STOP THE TRANSFUSION OF INFORMATION. Oxygen should be given to the patient. Around 75% of patients will require aggressive respiratory support.
The use of diuretics should be avoided.6) TACO (Transfusion Associated Circulatory Overload)
Acute or worsening respiratory distress within 6 hours of a large blood transfusion. Fluid overload and pulmonary and peripheral oedema can be seen. Rapid blood pressure rises are common. BNP is usually 1.5 times higher than it was before the transfusion. It is most common in the elderly and those who have chronic anaemia.Blood transfusions should be given slowly, over the course of 3-4 hours.
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This question is part of the following fields:
- Haematology
- Pathology
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Question 65
Correct
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Achlorhydria is diagnosed in a 37-year-old individual who has had recurring episodes of gastroenteritis. This is an autoimmune illness of the gastric parietal cells that causes insufficient stomach acid production.
Damage to stomach parietal cells will alter the secretion of which other substance?Your Answer: Intrinsic factor
Explanation:Achlorhydria is an autoimmune illness of the gastric parietal cells that causes insufficient stomach acid production. The parietal cells that have been injured are unable to create the necessary amount of stomach acid. As a result, the pH of the stomach rises, food digestion suffers, and the risk of gastroenteritis rises.
The secretion of hydrochloric acid and intrinsic factor is controlled by the gastric parietal cells, which are epithelial cells in the stomach. These cells can be found in the gastric glands, the fundus lining, and the stomach body.
In response to the following three stimuli, the stomach parietal cells release hydrochloric acid:
H2 Histamine receptors are stimulated by histamine (most significant contribution)
Acetylcholine stimulates M3 Receptors via parasympathetic action.
CCK2 receptors are stimulated by Gastrin.Intrinsic factor, which is essential for vitamin B12 absorption, is also produced by stomach parietal cells.
Omeprazole is a proton pump inhibitor that is both selective and irreversible. It inhibits the H+/K+-ATPase system present on the secretory membrane of gastric parietal cells, which lowers stomach acid secretion.
Ranitidine inhibits histamine H2-receptors in a competitive manner. The reversible inhibition of H2-receptors in gastric parietal cells reduces both the volume and concentration of gastric acid. -
This question is part of the following fields:
- Gastrointestinal Physiology
- Physiology
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Question 66
Correct
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Following the administration of a drug that was started a few months earlier, a patient presents with features of peripheral neuropathy.
Which of the following drugs is most likely to cause peripheral neuropathy?
Your Answer: Isoniazid
Explanation:Isoniazid, a first-line agent for the treatment of tuberculosis, has the commonest side effect of peripheral neuropathy. It occurs in up to 20% of patients taking the drug at a dose > 6 mg/kg daily.
Isoniazid combines with pyridoxine (vitamin B6) to form hydrazone, which is excreted in the urine. This causes a deficiency of biologically active pyridoxine leading to peripheral neuropathy.
Peripheral neuropathy of isoniazid is prevented by the co-administration of pyridoxine at a dose of 10 mg for each 100 mg of isoniazid given.
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This question is part of the following fields:
- Infections
- Pharmacology
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Question 67
Correct
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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: 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 68
Incorrect
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A 41-year-old female patient presents with jaundice. She tells you that she is known to have a chronic hepatitis B infection.
Which of the following hepatitis B serology results is consistent with a patient that is chronically infected? Select ONE answer only.Your Answer: HBsAg positive, anti-HBc positive, IgM anti-HBc positive
Correct Answer: HBsAg positive, anti-HBc positive, IgM anti-HBc negative
Explanation:Hepatitis B surface antigen (HBsAg) is a protein on the surface of the hepatitis B virus, that is the first serologic marker to appear in a new acute infection.It can be detected as early as 1 week and as late as 9 weeks. It can be detected in high levels in serum during acute or chronic hepatitis B virus infection. The presence of HBsAg indicates that the person is infectious. The body normally produces antibodies to HBsAg as part of the normal immune response to infection. HBsAg is the antigen used to make hepatitis B vaccine.
Hepatitis B surface antibody (anti-HBs) indicates recovery and immunity from the hepatitis B virus infection. Anti-HBs also develops in a person who has been successfully vaccinated against hepatitis B.
Total hepatitis B core antibody (anti-HBc): Appears at the onset of symptoms in acute hepatitis B and persists for life. The presence of anti-HBc indicates previous or ongoing infection with hepatitis B virus in an undefined time frame. It is not present following hepatitis B vaccination.
IgM antibody to hepatitis B core antigen (IgM anti-HBc) indicates recent infection with hepatitis B virus (<6 months). Its presence indicates acute infection.
The following table summarises the presence of hepatitis B markers according to each situation:
Susceptible to infection:
HBsAg = Negative
Anti-HBc = Negative
Anti-HBs = NegativeImmune due to natural infection:
HBsAg = Negative
Anti-HBc = Positive
Anti-HBs = PositiveImmune due to vaccination:
HBsAg = Negative
Anti-HBc = Negative
Anti-HBs = PositiveAcute infection:
HBsAg = Positive
Anti-HBc = Positive
Anti-HBs = Negative
IgM anti-HBc = PositiveChronic infection:
HBsAg = Positive
Anti-HBc = Positive
Anti-HBs = Negative
IgM anti-HBc = Negative -
This question is part of the following fields:
- Microbiology
- Specific Pathogen Groups
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Question 69
Incorrect
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On review of a patient's serum and urine osmolality test result, you note that both osmolarities are decreased. There urine osmolality does not increase with fluid ingestion.
What is the most likely cause?Your Answer: Diabetes insipidus
Correct Answer: Hyponatraemia
Explanation:As part of the investigation of hyponatraemia, serum osmolality is commonly requested in combination with urine osmolality to aid diagnosis.
When:
Serum osmolality is decreased and urine osmolality is decreased with no intake of fluid, the causes are
Hyponatraemia
Overhydration
Adrenocortical insufficiency
Sodium loss (diuretic or a low-salt diet)Serum osmolality is normal or increased and urine osmolality is increased the causes include:
Dehydration
Hyperkalaemia
Hyperglycaemia
Hyponatremia
Mannitol therapy
Diabetes mellitus
Alcohol ingestion
Congestive heart failure
Renal disease and uraemiaSerum osmolality is normal or increased and urine osmolality is decreased the usual cause is diabetes insipidus
Serum osmolality is decreased and urine osmolality is increased the usual cause is syndrome of inappropriate antidiuresis (SIAD)
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This question is part of the following fields:
- Basic Cellular Physiology
- Physiology
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Question 70
Correct
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All of the following cause bronchodilation, EXCEPT for:
Your Answer: Stimulation of irritant receptors
Explanation:Factors causing bronchodilation: Via beta2-adrenoceptors
Sympathetic stimulation:
Adrenaline (epinephrine)
Beta2-adrenergic agonists e.g. salbutamol
Anticholinergic and muscarinic antagonists e.g. ipratropium -
This question is part of the following fields:
- Physiology
- Respiratory
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Question 71
Correct
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A 20-year-old asthmatic patient's symptoms is deteriorating and patient is moved to the resuscitation area of the Emergency Department. A loading dose of IV aminophylline is administered and her symptoms begin to improve. You are asked to check her theophylline levels after an appropriate time period.
How long should you wait before taking her blood sample be taken?
Your Answer: 4-6 hours
Explanation:Plasma theophylline concentration is usually measured five days after starting oral treatment and three days after each dose adjustment.
A blood sample to check theophylline concentration should usually be taken after 4-6 hours if an IV dose of aminophylline was given.
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This question is part of the following fields:
- Pharmacology
- Respiratory Pharmacology
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Question 72
Correct
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Herpes simplex virus is transmitted most commonly through which of the following routes:
Your Answer: Direct contact spread
Explanation:Herpes simplex virus is the most common cause of infective encephalitis and has a predilection for the temporal lobes. Herpes simplex is transmitted through direct contact. It invades skin locally producing skin vesicles by its cytolytic activity.
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This question is part of the following fields:
- Microbiology
- Pathogens
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Question 73
Incorrect
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Mast cells play a significant part in which of the following?
Your Answer: Killing virus infected cells
Correct Answer: Allergic disease
Explanation:Mast cells play a central role in the response to allergen challenges. The activation of mast cells results in both an early and a delayed phase of inflammation. Mast cells have been implicated in both physiologic and pathogenic processes. Mast cells are important in defence against some bacteria and viruses and contribute to defence against parasites. They are key effector cells in both innate and acquired immunity and are capable of inducing and amplifying both types of responses. Specifically, mast cells are capable of detecting microbial products through surface pattern recognition receptors, and they are involved in the recruitment of other leukocytes, containment of bacterial infections, and tissue repair.
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This question is part of the following fields:
- Immune Responses
- Pathology
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Question 74
Incorrect
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Identify the type of graph described below:
This graph has been used to create visual representations to communicate the risks and benefits of treatments using 4 face categories.Your Answer: Pareto diagram
Correct Answer: Cates plot
Explanation:Cates Plot, since 1999, has been used to create visual representations to communicate the risks and benefits of treatments. The essence of Cates Plot is the use of 4 face categories to visually indicate the following:
People not affected by a treatment (green faces for those with a good outcome and red for those with a bad outcome)
People for which treatment changes their category from a bad outcome to a good outcome (yellow faces)
People for which treatment causes an adverse event and changes their category from a good outcome to a bad outcome (crossed out green faces) -
This question is part of the following fields:
- Evidence Based Medicine
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Question 75
Incorrect
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You received a patient with a 2-day history of diarrhoea and vomiting. Later, after examination, the patient was found to have progressive symmetric descending flaccid paralysis, initial development of blurred vision, dysphagia, and weakness of the upper limbs. The patient is apyrexial and his observations are all normal. Which of the following pathogens is responsible for the said symptoms?
Your Answer: Clostriodum perfringens
Correct Answer: Clostridium botulinum
Explanation:A botulism infection results in neuroparalysis caused by the neurotoxin generated by Clostridium botulinum.
Food-borne botulism symptoms often appear 12-36 hours after ingestion of the toxin-containing food and may include nausea, vomiting, stomach discomfort, and diarrhoea at first. The most common neurological pattern is an acute onset of bilateral cranial neuropathies with symmetric declining weakening.
Other distinguishing characteristics include the absence of fever, the absence of cognitive abnormalities, the presence of a normal heart rate and blood pressure, and the absence of sensory defects.
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This question is part of the following fields:
- Microbiology
- Pathogens
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Question 76
Correct
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Regarding Clostridium perfringens, which of the following statements is CORRECT:
Your Answer: It can cause exotoxin-mediated food poisoning.
Explanation:Clostridium perfringens is an obligate anaerobe and has exotoxin mediated effects. It is the most common cause of gas gangrene. C. perfringens is also implicated in food poisoning, cellulitis, enteritis necrotican (life-threatening infection involving ischaemic necrosis of the jejunum), and rarely, CNS infections such as meningitis and encephalitis.
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This question is part of the following fields:
- Microbiology
- Pathogens
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Question 77
Correct
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Which of the following is the most abundant immunoglobulin in plasma:
Your Answer: IgG
Explanation:IgA is the major Ig in secretions, particularly from the gastrointestinal tract (but also in saliva, tears, sweat and breast milk).
IgE is important for mast cell degranulation in allergic and antiparasitic response. In the allergic response, the plasma cell produces IgE-antibodies, which, like antibodies of other immunoglobulin isotypes, are capable of binding a specific allergen via its Fab portion.
IgG is the most abundant in plasma (comprising 80% of normal serum immunoglobulin) and the main circulatory Ig for the secondary immune response. -
This question is part of the following fields:
- Immune Responses
- Pathology
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Question 78
Correct
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A 50-year-old man presents with headaches, lethargy, hypertension, and electrolyte disturbance. A diagnosis of primary hyperaldosteronism is made.
Which biochemical pictures would best support this diagnosis?
Your Answer: Hypokalaemic metabolic alkalosis
Explanation:When there are excessive levels of aldosterone outside of the renin-angiotensin axis, primary hyperaldosteronism occurs. High renin levels will lead to secondary hyperaldosteronism.
The classical presentation of hyperaldosteronism when symptoms are present include:
Hypokalaemia
Metabolic alkalosis
Hypertension
Normal or slightly raised sodium levels -
This question is part of the following fields:
- Endocrine Physiology
- Physiology
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Question 79
Correct
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Which of the following is characterised by passive carrier-mediated transport down a chemical concentration gradient:
Your Answer: Facilitated diffusion
Explanation:Facilitated diffusion is the process of spontaneous passive transport of molecules or ions down their concentration gradient across a cell membrane via specific transmembrane transporter (carrier) proteins. The energy required for conformational changes in the transporter protein is provided by the concentration gradient rather than by metabolic activity.
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This question is part of the following fields:
- Basic Cellular
- Physiology
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Question 80
Correct
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The patient is a 78-year-old woman who has recently developed left-sided hemiplegia. A CT head scan is performed, and the diagnosis of an ischaemic stroke is confirmed. Her blood pressure is currently very high, with the most recent measurement being 196/124 mmHg, according to the nurse in charge. While you wait for the stroke team to review her, she asks you to prescribe something to help lower the patient's blood pressure.
Which of the following is the best drug treatment for this patient's BP reduction?Your Answer: Labetalol
Explanation:End-organ damage (e.g. encephalopathy, intracranial haemorrhage, acute myocardial infarction or ischaemia, dissection, pulmonary oedema, nephropathy, eclampsia, papilledema, and/or angiopathic haemolytic anaemia) characterises a hypertensive emergency (also known as ‘accelerated hypertension’ or malignant hypertension’ It’s a life-threatening condition that necessitates rapid blood pressure reduction to avoid end-organ damage and a negative outcome.
In the setting of a stroke syndrome (i.e., in the presence of focal neurological deficits), hypertensive emergencies usually necessitate a slower and more controlled blood pressure reduction than in other situations. Rapid reduction of MAP in the presence of an ischaemic stroke can compromise blood flow, leading to further ischaemia and worsening of the neurological deficit. In this situation, intravenous labetalol is the drug of choice for lowering blood pressure.
Significantly elevated blood pressure (>185/110 mmHg) is a contraindication to thrombolysis, but there is some evidence for controlling blood pressure before thrombolysis in exceptional circumstances, when it is only slightly above this threshold.
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This question is part of the following fields:
- Cardiovascular Pharmacology
- Pharmacology
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Question 81
Correct
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Which of the following does NOT predispose to digoxin toxicity in a patient taking digoxin:
Your Answer: Hyponatraemia
Explanation:Hypoxia, hypercalcaemia, hypokalaemia and hypomagnesaemia predispose to digoxin toxicity. Care should also be taken in the elderly who are particularly susceptible to digoxin toxicity. Hypokalaemia may be precipitated by use of diuretics. Although hyponatremia can result in the development of other pathological disturbances, it does not potentiate digoxin toxicity.
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This question is part of the following fields:
- Cardiovascular
- Pharmacology
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Question 82
Correct
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A 30-year-old man suffers from an open femoral shaft fracture after being involved in a road traffic accident. As a consequence of his injury, the nerve that was damaged innervates the popliteus muscle.
In which of the following nerves is the popliteus muscle innervated by?Your Answer: Tibial nerve
Explanation:The popliteus muscle is innervated by the tibial nerve (L4, 5 and S1).
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This question is part of the following fields:
- Anatomy
- Lower Limb
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Question 83
Incorrect
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A 71-year-old woman is treated with co-amoxiclav for a chest infection but she returns 1 week later. Her chest infection has resolved but she developed a profuse, offensive smelling diarrhoea and abdominal cramps. You suspect Clostridium difficile associated diarrhoea (CDAD).
ONE of these statements is true concerning this diagnosis.Your Answer: A positive stool culture for Clostridium difficile is the most specific test for this diagnosis
Correct Answer: The gold standard for the diagnosis of Clostridium difficile colitis is cytotoxin assay
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.
Currently, the gold standard for the diagnosis of Clostridium difficile colitis is cytotoxin assay. Stool culture to detect Clostridium difficile is not specific for pathogenic strains, is expensive and therefore not specific for a diagnosis of CDAD
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This question is part of the following fields:
- Microbiology
- Specific Pathogen Groups
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Question 84
Incorrect
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Which of the following laboratory findings is NOT typical of Hodgkin lymphoma:
Your Answer: Neutrophilia
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 85
Correct
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An very unwell patient is receiving treatment in your hospital's HDU and is found to have an Escherichia coli O157 infection.
Which one of these statements about Escherichia coli O157 is true?Your Answer: Haemolytic uraemic syndrome develops in approximately 6% of patients
Explanation:Escherichia coli O157 is a serotype of Escherichia coli.
The Escherichia coliO157 strain is ‘enterohaemorrhagic’ and causes severe forms of acute haemorrhagic diarrhoea. It can also cause non-haemorrhagic diarrhoea.Incubation period of Escherichia coli O157 is usually 3-4 days and bloody diarrhoea usually begins on the 3rd or 4th day of the infection.
Infections with Escherichia coliO157 are more common during the warmer months than in winter.
Haemolytic uraemic syndrome develops in approximately 6% of patients. It is commonly seen in children and in the elderly.
Escherichia coli O157 can also cause:
Haemorrhagic colitis
Haemolytic uraemic syndrome
Thrombotic thrombocytopenic purpura but not immune thrombocytopenic purpura. -
This question is part of the following fields:
- Microbiology
- Specific Pathogen Groups
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Question 86
Incorrect
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Regarding fibrinolytics, which of the following statements is INCORRECT:
Your Answer: Further embolism may occur either due to clots that break away from the original thrombus or to cholesterol crystal emboli.
Correct Answer: Fibrinolytic drugs act as thrombolytics by directly degrading the fibrin mesh and so breaking up thrombi.
Explanation:Fibrinolytic drugs act as thrombolytics by activating plasminogen to form plasmin, which degrades fibrin and so breaks up thrombi.
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This question is part of the following fields:
- Cardiovascular
- Pharmacology
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Question 87
Correct
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A 66-year-old male is brought to your clinic by his wife with the complaint of increasing confusion and disorientation over the past three days, along with decreased urination. She reports that he has been complaining of increasing pain in his back and ribs over the past three months.
On examination, the patient looks anaemic, is not oriented in time, place and person and has tenderness on palpation of the lumbar spine and the 10th, 11th and 12th ribs.
Blood tests show anaemia which is normocytic, normochromic, raised urea and creatinine and hypercalcemia.
Which one of the following diagnoses is most likely in this case?Your Answer: Multiple myeloma
Explanation:Multiple myeloma is a clonal abnormality affecting plasma cells in which there is an overproduction of functionless immunoglobulins. The most common patient complaint is bone pain, especially in the back and ribs. Anaemia and renal failure are common, along with hypercalcemia. Hypercalcemia may lead to an altered mental status, as in this case.
Chronic lymphocytic leukaemia occurs due to the overproduction of lymphocytes, usually B cells. CLL may present with an asymptomatic elevation of B cells. Patients are generally more than 50 years old and present with non-specific fatigue and weight loss symptoms.
There is no history of alcohol abuse in this case. Furthermore, patients with a history of alcohol abuse may have signs of liver failure, which are not present here.
Metastatic prostate cancer would most often cause lower backache as it metastasises first to the lumbar spine via the vertebral venous plexus.
A patient with Vitamin B12 deficiency would have anaemia, megaloblastic, hypersegmented neutrophils, and signs of peripheral neuropathy.
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This question is part of the following fields:
- Haematology
- Pathology
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Question 88
Incorrect
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A clinical audit cycle comprises of 5 steps. Each of these processes are listed below:
Which is the correct order that these should occur?
1. Observation of practice and collection of data
2. Identification of the problem
3. Implementation of change
4. Definition of criteria and setting of standards
5. Analysis of data and comparison of performance with the criteria and standardsYour Answer: 1,5,2,4,3
Correct Answer: 2,4,1,5,3
Explanation:An audit assesses if a certain aspect of health care is attaining a recognized standard. This lets care providers and patients know where their service is doing well, and where there could be improvements. The aim is to achieve quality improvement and improve outcomes for patients.
Audits are a quality improvement measure and one of the 7 pillars of clinical governance. It allows organizations to continually work toward improving quality of care by showing them where they are falling short, allows them to implement improvements, and reaudit or close the audit cycle to see if beneficial change has taken place.
Clinical audits are a cycle with several steps:
1. Identification of the problem
2. Definition of criteria and setting of standards
3. Observation of practice and collection of data
4. Analysis of data and comparison of performance with the criteria and standards
5. Implementation of change -
This question is part of the following fields:
- Evidence Based Medicine
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Question 89
Correct
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Which of the following is NOT a common side effect of amiodarone:
Your Answer: Blue/green teeth discolouration
Explanation:Common side effects of amiodarone include: Bradycardia, Nausea and vomiting, Thyroid disorders – hypothyroidism and hyperthyroidism, Persistent slate grey skin discoloration, Photosensitivity, Pulmonary toxicity (including pneumonitis and fibrosis), Hepatotoxicity, Corneal microdeposits (sometimes with night glare), Peripheral neuropathy and Sleep disorders.
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This question is part of the following fields:
- Cardiovascular
- Pharmacology
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Question 90
Incorrect
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One of these statements about cohort studies is true:
Your Answer: They are usually shorter in duration than case-control studies
Correct Answer: They are longitudinal in nature
Explanation:A cohort study is a longitudinal, observational study. It follows a group of patients (the cohort) forward in time and monitors the effects of the aetiological factor under study upon them.
Cohort studies are usually of longer duration and are more expensive than case-control studies. They, however, provide more useful and reliable information.
Cohort studies follow a cohort of patients who don’t have a disease and evaluate the absolute and relative risk of contracting the disease after exposure to the aetiological agent.
Cross-sectional studies are the best way to determine the prevalence of a disease. while Cohort studies are better at determining the incidence of a disease.
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This question is part of the following fields:
- Evidence Based Medicine
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Question 91
Incorrect
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Which one of these infectious diseases typically has an incubation period of between 1 and 3 weeks?
Your Answer: Hepatitis A
Correct Answer: Chickenpox
Explanation:The incubation period for Chickenpox is 7-23 days (usually around 2 weeks).
Incubation period of botulism is 18-36 hours
Incubation period of Meningococcaemia is 1-7 days.
Incubation period of Gonorrhoea is 3-5 days.
Incubation period of Hepatitis A is 3-5 weeks.
Other infectious with an incubation period of between 1 and 3 weeks are:
Whooping cough (7-10 days)
Brucellosis (7-21 days)
Leptospirosis (7-12 days)
Malaria (7-40 days depending on strain)
Typhoid (8-21 days)
Measles (10-18 days)
Mumps (14-18 days)
Rubella (14-21 days) -
This question is part of the following fields:
- Microbiology
- Specific Pathogen Groups
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Question 92
Incorrect
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Which of the following pathogens is most commonly implicated in croup:
Your Answer: Respiratory syncytial virus
Correct Answer: Parainfluenza
Explanation:Parainfluenza virus is the most commonly implicated infectious agent in croup.
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This question is part of the following fields:
- Microbiology
- Pathogens
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Question 93
Correct
-
Depolarisation of a neuron begins with which of the following:
Your Answer: Opening of ligand-gated Na + channels
Explanation:Action potentials are initiated in nerves by activation of ligand-gated Na+channels by neurotransmitters. Opening of these Na+channels results in a small influx of sodium and depolarisation of the negative resting membrane potential (-70 mV). If the stimulus is sufficiently strong, the resting membrane depolarises enough to reach threshold potential (generally around -55 mV), at which point an action potential can occur. Voltage-gated Na+channels open, causing further depolarisation and activating more voltage-gated Na+channels and there is a sudden and massive sodium influx, driving the cell membrane potential to about +40 mV.
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This question is part of the following fields:
- Basic Cellular
- Physiology
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Question 94
Correct
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A young male has presented to the Emergency Department with a sudden onset of severe palpitations, shortness of breath, and chest pain. A 12-lead ECG is recorded, and it shows a narrow complex tachycardia that points to a diagnosis of supraventricular tachycardia.
Vagal manoeuvres are attempted but are unsuccessful in eliminating the arrhythmia. The next action plan is to use a drug to revert to sinus rhythm.
Out of the following, which is the first-line treatment for supraventricular tachycardia?Your Answer: Adenosine
Explanation:Paroxysmal supraventricular tachycardia is an intermittent tachycardia (HR > 100 bpm) and has the following characteristics:
1. Sudden onset/offset (Contrast with sinus tachycardia)
2. Electrical activity originates above the ventricle (Contrast with ventricular tachycardia)
3. Produces narrow QRS complex (<120ms) The most common cause of PSVT is Atrioventricular nodal re-entrant tachycardia (AVNRT), most common in young women with a mean age onset of 32 years old. There are recurrent episodes of palpitations, and most of the episodes spontaneously. Sometimes, some vagal manoeuvres are required:
1. Valsalva manoeuvre
2. immersing the face in ice-cold water
3. carotid sinus massage.If PSVT keeps persisting or is causing severe symptoms, the treatment of choice is intravenous adenosine. The patient’s ECG should be continuously monitored throughout the treatment.
The recommended doses in adults are as follows:
– Initial dose of adenosine is 6 mg by rapid IV bolus
– If unsuccessful, give another dose of adenosine 12 mg by rapid IV bolus
– If unsuccessful, give a further dose of adenosine 12 mg by rapid IV bolus
The latest ALS guidelines advocate 18 mg for the third dose, whereas the BNF/NICE guidelines advocate 12 mg.If adenosine fails or is contraindicated, intravenous verapamil can be used as an alternative, but it should be avoided in patients recently treated with beta-blockers.
Synchronized electrical cardioversion will be necessary with signs of hemodynamic instability or if drug treatment has failed to restore sinus rhythm.
Recurrent episodes of paroxysmal supraventricular tachycardia can be treated by catheter ablation or prevented with drugs such as flecainide, sotalol, diltiazem, or verapamil. -
This question is part of the following fields:
- Cardiovascular Pharmacology
- Pharmacology
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Question 95
Incorrect
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All of the following statements are considered true regarding likelihood ratios, except:
Your Answer: They apply to a piece of diagnostic information
Correct Answer: If less than one, indicates that the information increases the likelihood of the suspected diagnosis
Explanation:The Likelihood Ratio (LR) is the likelihood that a given test result would be expected in a patient with the target disorder compared to the likelihood that that same result would be expected in a patient without the target disorder.
The LR is used to assess how good a diagnostic test is and to help in selecting an appropriate diagnostic tests or sequence of tests. They have advantages over sensitivity and specificity because they are less likely to change with the prevalence of the disorder, they can be calculated for several levels of the symptom/sign or test, they can be used to combine the results of multiple diagnostic test and they can be used to calculate post-test probability for a target disorder.
A LR greater than 1 produces a post-test probability which is higher than the pre-test probability. An LR less than 1 produces a post-test probability which is lower than the pre-test probability. When the pre-test probability lies between 30 and 70 per cent, test results with a very high LR (say, above 10) rule in disease. An LR below 1 produces a post-test probability les than the pre-test probability. A very low LR (say, below 0.1) virtually rules out the chance that the patient has the disease.
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This question is part of the following fields:
- Evidence Based Medicine
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Question 96
Incorrect
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Regarding the accessory nerve, which of the following statements is INCORRECT:
Your Answer: The nerve originates from cervical segments C1 - C5.
Correct Answer: Accessory nerve palsy results in the inability to nod the head
Explanation:Accessory nerve palsy results in inability to shrug the shoulders and to rotate the head to look at the opposite side to the lesion.
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This question is part of the following fields:
- Anatomy
- Cranial Nerve Lesions
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Question 97
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 98
Correct
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A 22 year old male has been stabbed and is brought to the ED with a stab wound to his upper limb. On examination, the patient is unable to flex the distal interphalangeal joints of the ring and little finger. However, the proximal interphalangeal joint is intact. The most likely affected nerve is which of the following, and at which level is this occurring?
Your Answer: Ulnar nerve at elbow
Explanation:The medial half of the flexor digitorum profundus is innervated by the ulnar nerve. Paralysis of this muscle results in loss of flexion at the distal interphalangeal joint of the ring and little finger.
Flexion at the proximal interphalangeal joint is preserved as this is a function of the flexor digitorum superficialis which is innervated by the median nerve.
The ulnar nerve is not correct as ulnar nerve injury at the wrist would not affect the long flexors, and the injury must have been more proximal. -
This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 99
Correct
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You're taking a history of a 59-year-old banker who has had heartburn in the past.
Which of the following information about antacids is correct?Your Answer: Magnesium carbonate can reduce the absorption of drugs taken at the same time
Explanation:Antacids such as aluminium hydroxide and magnesium carbonate are commonly used. They’re both water-insoluble and can reduce the absorption of drugs taken together. Allow at least 1-2 hours between taking these antacids and any other medications.
Because it reduces gastrointestinal phosphate absorption, aluminium hydroxide can also be used to treat hyperphosphatemia in patients with renal failure.
Magnesium carbonate has a laxative effect, whereas aluminium hydroxide has a constipating effect.
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This question is part of the following fields:
- Gastrointestinal Pharmacology
- Pharmacology
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Question 100
Correct
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A 47-year-old woman comes in with palpitations that have been bothering her for the past four days. Her haemodynamics are normal, but her heart rate is currently 150 beats per minute. An ECG is performed, which reveals that she is experiencing atrial flutter. The patient is examined by a cardiology registrar, who recommends starting her on verapamil to control her ventricular rate while she waits for cardioversion.
In these circumstances, which of the following is a contraindication to the use of verapamil?Your Answer: Acute porphyria
Explanation:In most cases of atrial flutter, ventricular rate control is used as a stopgap measure until sinus rhythm is restored. A beta-blocker (e.g. bisoprolol), diltiazem, or verapamil can be used to reduce the rate of contractions in the heart.
Electrical cardioversion, pharmacological cardioversion, and catheter ablation can all be used to return the heart to a normal rhythm. Cardioversion should not be attempted until the patient has been fully anticoagulated for at least three weeks if the duration of atrial flutter is unknown or it has lasted longer than 48 hours. Emergency electrical cardioversion is the treatment of choice when there is a sudden onset of symptoms and haemodynamic compromise. For recurrent atrial flutter, catheter ablation is preferred.Verapamil is a calcium-channel blocker that is non-dihydropyridine phenylalkylamine and can be used to treat supraventricular arrhythmias. It’s a calcium channel blocker with a high negative inotropic effect that lowers cardiac output, slows the heart rate, and may impair atrioventricular conduction. At high doses, it can cause heart failure, exacerbate conduction disorders, and cause hypotension.
Adults should take 240-480 mg of verapamil in 2-3 divided doses. 5-10 mg IV over 30 seconds is the corresponding intravenous (IV) dose. After an IV injection, the peak effect lasts 3-5 minutes, and the action lasts 10-20 minutes.
Verapamil should not be taken with beta-blockers like atenolol or quinidine because the combination of their negatively inotropic and negatively chronotropic effects can result in severe hypotension, bradycardia, impaired atrioventricular conduction, heart failure (due to impaired cardiac contractility), and sinus arrest.
The use of verapamil is contraindicated in the following situations:
Acute porphyrias are a type of porphyria that occurs suddenly.
Accessory conducting pathways are linked to atrial flutter or fibrillation (e.g. Wolff-Parkinson-White-syndrome)
Bradycardia
Shock caused by the heart
Insufficiency of the heart (with reduced ejection fraction)
Left ventricular function has been significantly harmed in the past (even if controlled by therapy)
Hypotension (blood pressure less than 90 mmHg)
AV block in the second and third degrees
Sinusitis is a condition in which the sinuses become
Sino-atrial occlusion -
This question is part of the following fields:
- Cardiovascular Pharmacology
- Pharmacology
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SESSION STATS - PERFORMANCE PER SPECIALTY
