-
Question 1
Correct
-
You review a patient with urinary sepsis and decide to start her on gentamicin.
Which statement about gentamicin is true?
Your Answer: Ototoxicity is a dose-related effect
Explanation:Gentamicin, an aminoglycoside antibiotic, acts by binding to the 30S subunit of the bacterial ribosome inhibiting the binding of aminoacyl-tRNA, and thus prevents initiation of protein synthesis.
Gentamicin is given by injection because it is NOT absorbed orally.
It is excreted in the kidneys by glomerular filtration
Gentamicin is not to be used for the treatment of Neisseria meningitidis, Neisseria gonorrhoea, or Legionella pneumophila.There is a risk of patient going into shock from lipid A endotoxin release.
Two of its most notable side effects are hearing loss reversible nephrotoxicity and which are both dose-related and levels should be monitored in patients.
-
This question is part of the following fields:
- Infections
- Pharmacology
-
-
Question 2
Incorrect
-
A 22-year-old student presents with a painful, red and itchy right eye. On examination, there is mild erythema of palpebral conjunctiva, and follicles are visible on eversion of the eyelid. Lid oedema is evident, and you can also see a few petechial subconjunctival haemorrhages. The eye appears watery, and there is no purulent discharge. He has recently recovered from a mild upper respiratory tract infection.
Which of these is the most likely causative organism?
Your Answer: Streptococcus pneumoniae
Correct Answer: Adenovirus
Explanation:The most frequent cause of red eye is conjunctivitis. It is caused by inflammation of the conjunctiva which can be infective or allergic and accounts for about 35% of all eye problems presenting to general practice.
Viral conjunctivitis is commonly caused by adenoviruses and it is the most common infectious conjunctivitis.
The common bacterial causes of conjunctivitis are Haemophilus influenzae, Streptococcus pneumoniae, and Staphylococcus aureus.
The clinical features of infective conjunctivitis include:
Acute onset of conjunctival erythema
Feeling ‘grittiness’, ‘foreign body’ or ‘burning’ sensation in the eye.
Watering and discharge which may cause transient blurring of visionFeatures of viral conjunctivitis include: watery and non-purulent eye discharge, lid oedema, follicles present on eyelid eversion, petechial subconjunctival haemorrhages and pseudomembranes may be seen on the tarsal conjunctival surfaces.
This patients features are consistent with a viral aetiology, and the most likely causative organism is adenovirus,
-
This question is part of the following fields:
- Microbiology
- Specific Pathogen Groups
-
-
Question 3
Correct
-
A 30-year-old male presents with easy bruising and bleeding gums, feeling very tired lately, and recurrent chest infections over the past few months. He had glandular fever approximately 6 months ago and feels that his symptoms started after that.
His full blood count today is as follows:
Hb 6.3 g/dl (11.5-14 g/dl)
MCV 90 fl (80-100 fl)
WCC 2.0 x 10 9 /l (4-11 x 10 9 /l)
Platelets 15 x 10 9 /l (150-450 x 10 9 /l)
The SINGLE most likely diagnosis is?Your Answer: Aplastic anaemia
Explanation:Aplastic anaemia is a life-threatening failure of haemopoiesis characterised by pancytopenia and hypocellular bone marrow. It is rare and patients present with features of recurrent infections secondary to (leukocytopenia), increased bleeding tendency (secondary to thrombocytopenia) and anaemia. In aplastic anaemia, there is damage to the bone marrow and the haematopoietic stems cells leading to pancytopenia.
-
This question is part of the following fields:
- Haematology
- Pathology
-
-
Question 4
Correct
-
The correct statement about the glomerular filtration barrier is which of the following?
Your Answer: The basement membrane is negatively charged, restricting filtration of negatively charged molecules.
Explanation:The main factor in determining whether a substance is filtered or not is molecular weight. Molecules < 7 kDa in molecular weight e.g. glucose, amino acids, urea, ions are filtered freely, but larger molecules are increasingly restricted up to 70 kDa, and there is very little filtration for anything above this.
There is further restriction of negatively charged molecules because they are repelled by negative charges, particularly in the basement membrane. Albumin, which has a molecular weight of 69 kDa and is negatively charged, is filtered but only in very small amounts. All of the filtered albumin is reabsorbed in the proximal tubule. Small molecules such as ions, glucose, amino acids and urea pass the filter without hindrance. Other than the ultrafiltrate being essentially protein free, it has an otherwise identical composition of plasma. Bowman’s capsule consists of:
– an epithelial lining which consists of a single layer of cells called podocytes
– endothelium which is perforated by pores or fenestrations – this allows plasma components with a molecular weight of < 70 kDa to pass freely. -
This question is part of the following fields:
- Physiology
- Renal
-
-
Question 5
Incorrect
-
Which of the following best describes an intention to treat analysis:
Your Answer: Only patients who were not lost to follow-up are included in the analysis.
Correct Answer: All patients are included in the analysis according to the group into which they were randomised even if they are withdrawn from the study.
Explanation:An intention to treat (ITT) analysis is one in which all patients are included in the analysis, classified according to the group into which they were randomised, even if they were withdrawn from the study and did not actually receive the treatment, did not comply with treatment or drop-out. Intention to treat analysis is a more reliable estimate of true treatment effectiveness by replicating what happens in the ‘real world’ (e.g. noncompliance and protocol violations commonly affect therapies).
-
This question is part of the following fields:
- Evidence Based Medicine
- Study Methodology
-
-
Question 6
Incorrect
-
Which of the following muscles is least likely to be involved in forceful expiration:
Your Answer: Transversus thoracis
Correct Answer: External intercostal muscles
Explanation:Forceful expiration is primarily produced by the deeper thoracic muscles (internal and innermost intercostal muscles, subcostals and transversus thoracis) aided by contraction of the abdominal wall muscles which increase intra-abdominal pressure thus further reducing the volume of the thorax.
-
This question is part of the following fields:
- Anatomy
- Thorax
-
-
Question 7
Incorrect
-
A 24-year-old waiter cuts his hand on a dropped plate that smashed and damages the nerve that innervates opponens digiti minimi.
The opponens digiti minimi muscle is innervated by which of the following nerves? Select ONE answer only.Your Answer: The superficial branch of the ulnar nerve
Correct Answer: The deep branch of the ulnar nerve
Explanation:Opponens digiti minimi is a triangular-shaped muscle in the hand that forms part of the hypothenar eminence. It originates from the hook of the hamate bone and the flexor retinaculum and inserts into the medial border of the 5thmetacarpal.
Opponens digiti minimi is innervated by the deep branch of the ulnar nerve and receives its blood supply from the ulnar artery.
Opponens digiti minimi draws the fifth metacarpal bone anteriorly and rotates it, bringing the fifth digiti into opposition with the thumb. -
This question is part of the following fields:
- Anatomy
- Upper Limb
-
-
Question 8
Correct
-
You evaluate a 80-year-old man who has a history of persistent heart failure and discover that he has generalised oedema.
Which of the following claims regarding capillary hydrostatic pressure (P c) is false?Your Answer: P c increases along the length of the capillary, from arteriole to venule
Explanation:The capillary hydrostatic pressure (Pc) is normally between 15 and 30 millimetres of mercury. Pc Decreases along the capillary’s length, mirroring the arteriolar and venule pressures proximally and distally.
Pc is determined by the ratio of arteriolar resistance (RA) to venular resistance (RV).When the RA/RV ratio is high, the pressure drop across the capillary is modest, and Pcis is close to venule pressure.
When the ratio of RA/RV is low, the pressure drop across the capillary is considerable, and Pcis is close to arteriolar pressure.
Pcis closer to the venule pressure and thus more responsive to changes in venous pressure than arteriolar pressure when RA/RV is high.
Pcis the major force behind fluid pushing out of the capillary bed and into the interstitium.
It is also the most variable of the forces affecting fluid transport at the capillary, partly because sympathetic-mediated arteriolar vasoconstriction varies. -
This question is part of the following fields:
- Cardiovascular Physiology
- Physiology
-
-
Question 9
Incorrect
-
Epigastric pain and haematemesis present in a 67-year-old man. In the emergency room, he is stabilised and referred to the on-call medical team. He has been scheduled for an endoscopy in the morning due to a suspected peptic ulcer. Before transferring him to the ward, you consider giving him a proton pump inhibitor (PPI).
Which of the following doses and routes are the best?Your Answer: Omeprazole 80 mg intravenously
Correct Answer: A PPI should not be prescribed
Explanation:PPIs should not be used prior to endoscopic therapy when an early endoscopic examination is performed within 24 hours of admission, according to current recommendations.
High-dose PPI therapy reduces the risk of rebleeding and surgery after endoscopic treatment of severe peptic ulcer bleeding. Both oral and intravenous PPIs produce similar results, and there is no discernible benefit to using the intravenous formulation in patients who can tolerate oral medication. -
This question is part of the following fields:
- Gastrointestinal Pharmacology
- Pharmacology
-
-
Question 10
Correct
-
A 45-year-old businessman returns from a trip to West Africa with headaches and intermittent fevers. Thick and thin films are sent to the lab and a diagnosis is made of malaria. The patient is started on treatment but his condition deteriorates and he develops jaundice, renal failure and haemoglobinuria.
Which of the following is the MOST likely causative organism? Select ONE answer only.Your Answer: Plasmodium falciparum
Explanation:Malaria is an infectious disease transmitted by female of theAnophelesgenus of mosquito. It is a parasitic infection caused by the genusPlasmodium. Five species are recognized as causing disease in humans;Plasmodium falciparum,Plasmodium ovale,Plasmodium vivax,Plasmodium malariaeandPlasmodium knowlesi.
The classic symptom of malaria is the malarial paroxysm, a cyclical occurrence of a cold phase, where the patient experiences intense chills, a hot stage, where the patient feels extremely hot and finally a sweating stage, where the fever declines and the patient sweats profusely. On examination the patient may show signs of anaemia, jaundice and have hepatosplenomegaly without evidence of lymphadenopathy.Plasmodium falciparum is the most serious form and is responsible for most deaths. Severe or complicated malaria is suggested by the presence of impaired consciousness, seizures, hypoglycaemia, anaemia, renal impairment, respiratory distress and spontaneous bleeding.
Plasmodium falciparum is the most likely type in this case in view of the presentation.
Haemoglobinuria and renal failure following treatment is suggestive of blackwater fever, which is caused byPlasmodium falciparum. An autoimmune reaction between the parasite and quinine causes haemolysis, haemoglobinuria, jaundice and renal failure. This can be fatal.
The benign malarias: P.vivax, P. malariae and P.ovale are usually treated with chloroquine. A course of primaquine is also required in P.vivax and P.ovale infection. Artesunate is the drug treatment of choice for Plasmodium falciparum malaria. Quinine can still be used where artesunate is not available. Often combination therapy with drugs such as doxycycline or fansidar is also required. -
This question is part of the following fields:
- Microbiology
- Specific Pathogen Groups
-
-
Question 11
Incorrect
-
Superficial fibular nerve palsy results in which of the following clinical features:
Your Answer: Loss of dorsiflexion of the great toe
Correct Answer: Loss of eversion of the foot
Explanation:Damage to the superficial fibular nerve results in loss of eversion of the foot and loss of sensation over the lower anterolateral leg and the dorsum of the foot.
-
This question is part of the following fields:
- Anatomy
- Lower Limb
-
-
Question 12
Incorrect
-
Antispasmodic drugs are primarily indicated in which of the following conditions:
Your Answer: Gastroenteritis
Correct Answer: Irritable bowel syndrome
Explanation:Antispasmodics, such as antimuscarinics, may be used in the management of irritable bowel syndrome. Other antispasmodics used include direct-acting smooth muscle relaxants such as mebeverine, alverine, and peppermint oil. Antispasmodics are contraindicated in bowel obstruction and severe inflammatory bowel disease. Antispasmodics are occasionally of value in treating abdominal cramp associated with diarrhoea but they should not be used for primary treatment. Antispasmodics should be avoided in young children with gastroenteritis because they are rarely effective and have troublesome side effects. Antimuscarinics are contraindicated in urinary retention.
-
This question is part of the following fields:
- Gastrointestinal
- Pharmacology
-
-
Question 13
Incorrect
-
Which of the following is NOT a characteristic of megaloblastic anaemia?
Your Answer: Decreased platelet count
Correct Answer: Raised reticulocyte count
Explanation:The LDH level is usually markedly increased in severe megaloblastic anaemia. Reticulocyte counts are inappropriately low, representing a lack of production of RBCs due to massive intramedullary haemolysis. These findings are characteristics of ineffective haematopoiesis that occurs in megaloblastic anaemia as well as in other disorders such as thalassemia major.
The common feature in megaloblastosis is a defect in DNA synthesis in rapidly dividing cells. To a lesser extent, RNA and protein synthesis are impaired. Unbalanced cell growth and impaired cell division occur since nuclear maturation is arrested. More mature RBC precursors are destroyed in the bone marrow prior to entering the bloodstream (intramedullary haemolysis). -
This question is part of the following fields:
- Haematology
- Pathology
-
-
Question 14
Incorrect
-
Regarding probability distribution, which of the following statements is CORRECT:
Your Answer: In a normal distribution the mean > median.
Correct Answer: In a negative skew, the mass of distribution is concentrated on the right.
Explanation:Distribution of data is usually unimodal (one peak) but may be bimodal (two peaks) or uniform (no peaks, each value equally likely). The normal distribution is a symmetrical bell-shaped curve. The mean, median, and mode of a normal distribution are equal. In a positive skew, the right tail is longer and the mass of distribution is concentrated on the left; mean > median > mode. In a negative skew, the left tail is longer and the mass of distribution is concentrated on the right; mean < median < mode.
-
This question is part of the following fields:
- Evidence Based Medicine
- Statistics
-
-
Question 15
Incorrect
-
In adults, the conus medullaris of the spinal cord lies at which of the following vertebral levels:
Your Answer: L4/L5
Correct Answer: L1/L2
Explanation:At birth, the conus medullaris lies at L3. By the age of 21, it sits at L1/L2.
-
This question is part of the following fields:
- Anatomy
- Head And Neck
-
-
Question 16
Correct
-
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.
-
This question is part of the following fields:
- Inflammatory Responses
- Pathology
-
-
Question 17
Correct
-
A 70-year-old man presents with right-sided hemiplegia and loss of joint position sense, vibratory sense, and discriminatory touch. Upon further physical examination, it was observed that her tongue deviates to the left-hand side. An MRI and CT scan was ordered and results showed that he was suffering a left-sided stroke.
Branches of which of the following arteries are most likely implicated in the case?Your Answer: Anterior spinal artery
Explanation:Medial medullary syndrome is a form of stroke that affects the medial medulla of the brain. It is caused by a lesion in the medial part of the medulla, which is due to an infraction of vertebral arteries and/or paramedian branches of the anterior spinal artery.
It is characterized by contralateral paralysis of the upper and lower limb of the body, a contralateral decrease in proprioception, vibration, and/or fine touch sensation, paresthesias or less commonly dysesthesias in the contralateral trunk and lower limb, and loss of position and vibration sense with proprioceptive dysfunction. Ipsilateral deviation of the tongue due to ipsilateral hypoglossal nerve damage can also be seen.
-
This question is part of the following fields:
- Anatomy
- Central Nervous System
-
-
Question 18
Incorrect
-
A patient suffers an injury to the nerve that innervates gluteus medius.​
The gluteus medius muscle is innervated by which of the following nerves? Select ONE answer only.Your Answer: Sciatic nerve
Correct Answer: Superior gluteal nerve
Explanation:Gluteus minimus is innervated by the superior gluteal nerve.
Gluteus medius is innervated by the superior gluteal nerve.
Gluteus maximus is innervated by the inferior gluteal nerve. -
This question is part of the following fields:
- Anatomy
- Lower Limb
-
-
Question 19
Incorrect
-
How does dipyridamole mediate its antiplatelet effect:
Your Answer: It is a GPIIb/IIIa inhibitor.
Correct Answer: It is a phosphodiesterase inhibitor.
Explanation:Dipyridamole inhibits both the reuptake of adenosine and phosphodiesterase, preventing the degradation of cAMP and thus blocking the platelet aggregation response to ADP.
-
This question is part of the following fields:
- Haematology
- Pathology
-
-
Question 20
Incorrect
-
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: Sternocleidomastoid
Correct Answer: Sternothyroid
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
-
SESSION STATS - PERFORMANCE PER SPECIALTY
