-
Question 1
Incorrect
-
A 74-year-old man who has been diagnosed with atrial fibrillation and heart failure is being started on digoxin. What is the mechanism of action of digoxin?
Your Answer: inhibits the Na+/K+ ATPase pump
Correct Answer:
Explanation:Digoxin acts by inhibiting the Na+/K+ ATPase pump.
Digoxin is a cardiac glycoside now mainly used for rate control in the management of atrial fibrillation. As it has positive inotropic properties it is sometimes used for improving symptoms (but not mortality) in patients with heart failure.Mechanism of action:
It decreases the conduction through the atrioventricular node which slows the ventricular rate in atrial fibrillation and atrial flutter.
It increases the force of cardiac muscle contraction due to inhibition of the Na+/K+ ATPase pump. It also stimulates the vagus nerve.Digoxin toxicity:
Plasma concentration alone does not determine whether a patient has developed digoxin toxicity. The likelihood of toxicity increases progressively from 1.5 to 3 mcg/l.
Clinical feature of digoxin toxicity include a general feeling of unwell, lethargy, nausea & vomiting, anorexia, confusion, xanthopsia, arrhythmias (e.g. AV block, bradycardia), and gynaecomastiaPrecipitating factors:
Hypokalaemia
Increasing age
Renal failure
Myocardial ischemia
Hypomagnesaemia, hypercalcemia, hypernatremia, acidosis
Hypoalbuminemia
Hypothermia
Hypothyroidism
Drugs: amiodarone, quinidine, verapamil, diltiazem, spironolactone (competes for secretion in the distal convoluted tubule, therefore, reduce excretion), ciclosporin. Also, drugs that cause hypokalaemia e.g. thiazides and loop diuretics.Management of digoxin toxicity:
Digibind
Correct arrhythmias
Monitor and maintain potassium levels within the normal limits. -
This question is part of the following fields:
- Pharmacology
-
-
Question 2
Correct
-
A neonate was brought in by her mother, for a skin lesion present over the neonate's back which is bluish in colour, but otherwise asymptomatic. The most appropriate course of action will be?
Your Answer: Reassure
Explanation:A Mongolian spot can be present in new born babies which usually appears over the back and fades with time. There is nothing to worry about.
-
This question is part of the following fields:
- Dermatology
-
-
Question 3
Correct
-
A young man is reviewed for difficulty breathing. Lung function tests showed that his peak expiratory flow rate is 54% below the normal range for his age and height. What is a possible diagnosis?
Your Answer: Asthma
Explanation:Peak Expiratory Flow (PEF), also called Peak Expiratory Flow Rate (PEFR) is a person’s maximum speed of expiration, as measured with a peak flow meter. Measurement of PEFR requires some practise to correctly use a meter and the normal expected value depends on a patient’s gender, age and height.
It is classically reduced in obstructive lung disorders, such as Asthma, COPD or Cystic Fibrosis. -
This question is part of the following fields:
- Respiratory
-
-
Question 4
Correct
-
A 60-year-old male is under treatment with azathioprine after a renal transplant. During his review, he complains of pain and swelling over his left great toe. Investigations reveal hyperuricemia. Suspecting gout, he was started on allopurinol. Subsequently, he develops aplastic anaemia. Which of the following is the most appropriate reason for his bone marrow failure?
Your Answer: Mercaptopurine toxicity
Explanation:The cause for bone marrow suppression in this patient is most probably mercaptopurine toxicity.
Azathioprine is metabolized to 6-mercaptopurine (6-MP), which itself is metabolized by xanthine oxidase.
Xanthine oxidase inhibition by allopurinol leads to the accumulation of 6-MP which then precipitates bone marrow failure.
This may be potentially fatal if unrecognized.
Clinical presentation:
Toxicity symptoms include gastrointestinal symptoms, bradycardia, hepatotoxicity, myelosuppression. -
This question is part of the following fields:
- Pharmacology
-
-
Question 5
Correct
-
A 32-year-old man, originally from Pakistan, was admitted with ascites and weight loss. The protein level on ascitic tap was 9 g/l. Which of the following is the most likely cause of this presentation?
Your Answer: Hepatic cirrhosis
Explanation:This is a low protein level, indicating the fluid is transudative. The only answer choice that is a transudative fluid is in hepatic cirrhosis. Exudative fluid would be seen in tuberculous peritonitis, peritoneal lymphoma, with liver mets, and with intra-abdominal malignancy.
-
This question is part of the following fields:
- Gastroenterology
-
-
Question 6
Incorrect
-
A 70-year-old retired software developer with a history of primary open-angle glaucoma presents with sudden painless loss of vision in his right eye. On examination of the right eye, the optic disc is swollen with multiple flame-shaped and blot haemorrhages. Which of the following is the most likely diagnosis?
Your Answer: Diabetic retinopathy
Correct Answer: Occlusion of central retinal vein
Explanation:Central retinal vein occlusion includes features such as sudden painless loss of vision, but is distinguished from central retinal artery occlusion by the presence of severe retinal haemorrhages on fundoscopy examination.
-
This question is part of the following fields:
- Ophthalmology
-
-
Question 7
Correct
-
An 18 year old girl presents with short history of marked, right hip pain and an associated limp. She has a history of acute lymphoblastic leukaemia for which she completed treatment for last six months.
Your Answer: Avascular necrosis of the femoral head
Explanation:Avascular necrosis (AVN) of the femoral head is a pathological process that results from disruption of the blood supply to the bone and occurs most commonly in the femoral epiphysis. Patients usually present with pain and limited joint motion. The mechanism involves impaired circulation to a specific area that ultimately becomes necrotic. AVN is most frequently associated with high doses of oral and intravenous corticosteroids and prolonged duration of therapy. Cancer patients receiving chemotherapy are usually also treated with corticosteroids.
-
This question is part of the following fields:
- Rheumatology
-
-
Question 8
Incorrect
-
A 51 year-old teacher presents complaining of numerous falls. He states he has difficulty walking up stairs, and he thinks it is because of his weak legs rather than blackouts. He is hypertensive and has suffered chronic back pain for many years. He has smoked for many years as well and has a chronic smokers cough. Upon examination, he has weakness of hip flexion and particularly knee extension. He is unable to keep his fingers flexed against force, with the right being weaker than the left. There are no sensory abnormalities and reflexes are preserved bilaterally. Which of the following is the most likely diagnosis?
Your Answer: Limb-girdle muscular dystrophy
Correct Answer: Inclusion body myositis
Explanation:The pattern of muscle involvement seen with quadriceps and long-finger flexors is characteristic of inclusion body myositis, an inflammatory myopathy. Polymyositis is likely to cause a predominantly proximal weakness, associated with muscle pain. The signs and symptoms are not consistent with upper cord compression, as there would likely be sensory signs, reflex changes, and possible urinary symptoms. Motor neuron disease cannot be ruled out, but there are no findings of upper motor neuron or bulbar features.
-
This question is part of the following fields:
- Neurology
-
-
Question 9
Correct
-
A 41-year-old gentleman undergoes a temporal lobectomy after the discovery of a brain tumour. Which one of the following consequences would be least likely to develop?
Your Answer: Astereognosis
Explanation:Astereognosis is associated with lesions to the parietal lobe, not the temporal lobe, so this symptom would not arise in this patient.
-
This question is part of the following fields:
- Neurology
-
-
Question 10
Incorrect
-
A 70 year old male complained of poor vision at night which has gradually worsened with time. He has changed his glasses several times but there has been no improvement. On examination his pupils and cornea were normal. Which of the following is the most probable diagnosis?
Your Answer:
Correct Answer: Cataract
Explanation:Senile cataract is an age-related, vision-impairing disease characterized by gradual progressive clouding and thickening of the lens of the eye. Patients with senile cataracts often present with a history of gradual progressive visual deterioration and disturbance in night and near vision.
-
This question is part of the following fields:
- Ophthalmology
-
SESSION STATS - PERFORMANCE PER SPECIALTY
