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Question 1
Correct
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Which of the following causes the first heart sound?
Your Answer: Closing of the atrioventricular valves
Explanation:The heart sounds are as a result of the various parts of the cardiac cycle.
Heart Sound – Phase of Cardiac Cycle – Mechanical Event:
1st heart sound – Systole starts – there is closure of the atrioventricular (mitral & tricuspid) valves
2nd heart sound – Systole ends – there is closure of the semilunar (aortic and pulmonary) valves
3rd heart sound – Early diastole – this is caused by rapid flow of blood from the atria into the ventricles during the ventricular filling phase
4th heart sound – Late diastole – this is caused by filling of an abnormally stiff ventricle in atrial systole -
This question is part of the following fields:
- Cardiovascular
- Physiology
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Question 2
Incorrect
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Coagulative necrosis is typically seen in which of the following:
Your Answer: Acute pancreatitis
Correct Answer: Myocardial infarction
Explanation:Coagulative necrosis is the most common form of necrosis characterised by the loss of cell nuclei, but with general preservation of the underlying architecture. Dead tissue is macroscopically pale and firm. This is the classic pattern seen in myocardial infarction.Liquefactive necrosis leads to complete loss of cellular structure and conversion into a soft, semi-solid mass. This is typically seen in the brain following cerebral infarction.Caseous necrosis is most commonly seen in tuberculosis. Histologically, the complete loss of normal tissue architecture is replaced by amorphous, granular and eosinophilic tissue with a variable amount of fat and an appearance reminiscent of cottage cheese.Gangrenous necrosis is necrosis with putrefaction of tissues due to exposure to air (dry gangrene) or infection (wet gangrene).
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This question is part of the following fields:
- Inflammatory Responses
- Pathology
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Question 3
Incorrect
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Which of the following is NOT a typical clinical feature of sickle cell disease:
Your Answer: Pigment gallstones
Correct Answer: Neutropaenia
Explanation:Features of sickle cell disease include:
Anaemia (symptoms are usually mild because the O2 dissociation curve of Hb S is shifted to the right)
Vaso-occlusive crisis
Visceral sequestration crisis
Aplastic crisisIncreased susceptibility to infection
Other clinical features: Pigment gallstones with cholecystitis
Chronic leg ulcers
Avascular necrosis of the femoral and humeral heads or other bones
Cardiomyopathy
Pulmonary hypertension
Proliferative retinopathy
Priapism
Renal papillary necrosis
Stroke -
This question is part of the following fields:
- Haematology
- Pathology
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Question 4
Correct
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A 6 year old boy is brought into the ED by his mom with a rash that is associated with Koplik's spots and a diagnosis of measles is made. What advice should be given about returning to school?
Your Answer: 4 days from the onset of the rash
Explanation:Prevention of spread of measles is extremely important and infected patients should be isolated. The infectious stage is from 3 days before the rash emerges and patients are advised to stay away from school/nursery/work for 4 days from onset of the rash.
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This question is part of the following fields:
- Microbiology
- Pathogens
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Question 5
Correct
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A 35 year old patient presents to ED having sustained an injury to his right hand whilst playing cricket. He is unable to fully straighten his right middle finger as the distal phalanx remains flexed. Which of the following structures within the digit was most likely injured:
Your Answer: Insertion of terminal extensor digitorum tendon
Explanation:Damage to the insertion of the terminal extensor digitorum tendon would result in loss of extension at the distal interphalangeal joint causing a fixed flexion deformity, called the Mallet deformity.
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This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 6
Incorrect
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A patient presents to your clinic with fever of unknown origin. His blood results shows a markedly elevated C-Reactive Protein (CRP) level.
Which of these is responsible for mediating the release of CRP?
Your Answer: IL-2
Correct Answer: IL-6
Explanation:C-reactive protein (CRP) is an acute phase protein produced by the liver hepatocytes. Its production is regulated by cytokines, particularly interleukin 6 (IL-6) and it can be measured in the serum as a nonspecific marker of inflammation.
Although a high CRP suggest an acute infection or inflammation, it does not identify the cause or location of infection.
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This question is part of the following fields:
- General Pathology
- Pathology
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Question 7
Correct
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Which of the following is NOT an effect of gastrin:
Your Answer: Stimulation of insulin release
Explanation:Gastrin acts to:
Stimulate acid secretion from parietal cells (both directly and indirectly by stimulating release of histamine from ECL cells)
Stimulate pepsinogen secretion from chief cells
Increase gastric motility
Stimulate growth of gastric mucosa -
This question is part of the following fields:
- Gastrointestinal
- Physiology
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Question 8
Correct
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A 34-year-old man presented to the emergency room after being involved in a road traffic accident. Upon observation and examination, it was noted that he was hypotensive and has muffled heart sounds. It was suspected that he has pericardial effusion, so an emergency pericardiocentesis was to be performed.
In performing pericardiocentesis for suspected pericardial effusion, which of the following anatomical sites are at risk of being punctured?Your Answer: 1 cm below the left xiphocostal angle
Explanation:Pericardiocentesis is a procedure done to remove fluid build-up in the sac around the heart known as the pericardium. The pericardium can be tapped from almost any reasonable location on the chest wall. However, for the usual blind pericardiocentesis, the subxiphoid approach is preferred. Ideally, 2-D echocardiography is used to guide needle insertion and the subsequent path of the needle/catheter.
In the subxiphoid approach, the needle is inserted 1 cm inferior to the left xiphocostal angle with an angle of 30 degrees from the patient’s chest with a direction towards the left mid-clavicle.
The fingers may sense a distinct give when the needle penetrates the parietal pericardium. Successful removal of fluid confirms the needle’s position.
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This question is part of the following fields:
- Abdomen And Pelvis
- Anatomy
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Question 9
Correct
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An analytical cohort study is done to compare the relationship between omega 3 intake and occurrence of myocardial infarction (MI) among males aged over 65 years. The following are the data from the study:
No. of subjects taking placebo: 100 men
No. of subjects taking placebo who suffered an MI: 15 men
No. of subjects taking omega 3: 100 men
No. of subjects taking omega 3 who suffered an MI: 5 men
Compute for the relative risk of the study.Your Answer: 0.33
Explanation:Relative risk (RR) is a ratio of the probability of an event occurring in the exposed group versus the probability of the event occurring in the non-exposed group.
RR can be computed as the absolute risk of events in the treatment group (ART), divided by the absolute risk of events in the control group (ARC).
RR = ART/ARC
RR = (5/100) / (15/100)
RR = 0.33 -
This question is part of the following fields:
- Evidence Based Medicine
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Question 10
Incorrect
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You've been summoned to a young man in the resus area who has an SVT. You decide to use adenosine after trying several vagal manoeuvres without success.
The use of adenosine is not contraindicated in which of the following situations?Your Answer: Long QT syndrome
Correct Answer: Concurrent use of a beta-blocker
Explanation:The use of a beta-blocker at the same time increases the risk of myocardial depression, but it is not a contraindication.
The use of adenosine is contraindicated in the following situations:
Asthma
COPD (chronic obstructive pulmonary disease)
Decompensated heart failure
Long QT syndrome
AV block in the second or third degree
Sinusitis is a condition in which the sinuses become (unless pacemaker fitted)
Hypotension that is severe -
This question is part of the following fields:
- Cardiovascular Pharmacology
- Pharmacology
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Question 11
Correct
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A patient is referred to the Medicine Department for complaints of unilateral hearing loss, tinnitus and facial numbness. Upon further investigation, an acoustic neuroma is given as the final diagnosis.
Which of the following nerves is least likely to be affected in acoustic neuroma?Your Answer: Trochlear nerve
Explanation:Acoustic neuroma is also called vestibular schwannoma (VS), acoustic neuroma, vestibular neuroma or acoustic neurofibroma. These are tumours that evolve from the Schwann cell sheath and can be either intracranial or extra-axial. They usually occur adjacent to the cochlear and vestibular nerves and most often arise from the inferior division of the latter. Anatomically, acoustic neuroma tends to occupy the cerebellopontine angle. About 5-10% of cerebellopontine angle (CPA) tumours are meningiomas and may occur elsewhere in the brain. Bilateral acoustic neuromas tend to be exclusively found in individuals with type 2 neurofibromatosis.
The following nerves may be affected due to nerve compression:
Facial nerve: usually minimal with late presentation except for very large tumours. Depending on the degree of engagement of the nerve, the symptoms may include twitching, increased lacrimation and facial weakness.
Trigeminal Nerve: paraesthesia in the trigeminal distribution, tingling of the tongue, impairment of the corneal reflex, and less commonly pain which may mimic typical trigeminal neuralgia.
Glossopharyngeal and Vagus nerves: palatal paresis, hoarseness of voice and dysphagia
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This question is part of the following fields:
- Anatomy
- Central Nervous System
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Question 12
Correct
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The patients listed below have had wounds or injuries and were treated as described in a local walk-in clinic.
Which of the following patients has had adequate tetanus protection?Your Answer: 80-year-old diabetic, a rusty nail went through his shoe and into his foot when walking in the woods, uncertain of vaccination history - receives vaccination and immunoglobulin
Explanation:25-year-old receives immunoglobulin and vaccination after cutting her hand on a drinking glass and not knowing her vaccination history.
Because this is not a tetanus-prone wound, immunoglobulin is not recommended. Because you can’t be sure about her vaccination history, now is the best time to start a tetanus vaccination course to ensure coverage later in life. The first vaccination should be administered at the time of presentation; the patient’s own GP should then review the patient’s vaccination history and schedule the rest of the course as needed.
8-year-old whose hand was cut with a kitchen knife, received her first round of vaccinations as a baby and a booster at the age of four – receives vaccination:
The tetanus vaccinations for this child are up to date, and the next booster should not be given too soon. Immunoglobulin is not required because this is not a tetanus-prone wound.80-year-old diabetic, a rusty nail went through his shoe and into his foot while walking in the woods, and he was uncertain of his vaccination history – he received vaccination and immunoglobulin:
A tetanus vaccination course may not have been completed by an 80-year-old UK resident (the vaccination was introduced in 1961). The vaccination should be given at a walk-in clinic, and the patient’s own GP should be contacted to confirm vaccination history and to schedule the rest of the course as needed. Because this is a tetanus-prone wound (puncture wound and potential soil contact), immunoglobulin would be recommended in a patient with incomplete tetanus vaccinations.A 28-year-old Polish man cuts his leg while working in the garden, the wound is heavily contaminated with soil, and his vaccination history is unknown – he receives vaccination:
In a patient with an unknown vaccination history, this is a tetanus-prone wound. In this case, the best course of action would be to administer both the vaccination and immunoglobulin at the walk-in clinic, then contact the patient’s own GP to check his or her vaccination history and schedule the rest of the course as needed.30-year-old with a large amount of devitalized tissue in the torso from an electrical burn – has had all vaccinations, so no need for vaccination or immunoglobulin:
Because this is a high-risk tetanus wound (with a lot of devitalized tissue), even if the patient has had a full course of vaccinations in the past, immunoglobulin is recommended. There is no need for any additional vaccinations. -
This question is part of the following fields:
- Immunological Products & Vaccines
- Pharmacology
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Question 13
Correct
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Regarding fat digestion, which of the following statements is CORRECT:
Your Answer: Chylomicrons are exocytosed from enterocytes to enter lacteals and thus the lymphatic system.
Explanation:Dietary fat is chiefly composed of triglycerides (esters of free fatty acids and glycerol which may be saturated or unsaturated). The essential fatty acids are linoleic acid and alpha-linoleic acid, which cannot be manufactured in the body. Dietary fat provides 37 kJ (9 kcal) of energy per gram. Fats are digested almost entirely in the small intestine and are only released from the stomach into the duodenum at the rate at which they can be digested.
Pancreatic lipase is the most significant enzyme for fat digestion. In the duodenum fat is emulsified by bile acids, a process where larger lipid droplets are broken down into much smaller droplets providing a greater surface area for enzymatic digestion. Micelles are arranged so that hydrophobic lipid molecules lie in the centre, surrounded by bile acids arranged such the outer region is hydrophilic. Dietary and synthesised lipids are incorporated into chylomicrons in the Golgi body, which are exocytosed from the basolateral membrane to enter lacteals and thus the lymphatic system. -
This question is part of the following fields:
- Gastrointestinal
- Physiology
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Question 14
Correct
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Which of the following microbes binds strongly to CD4 antigen:
Your Answer: HIV
Explanation:HIV mainly infects CD4+ T helper cells. Viral replication results in progressive T-cell depletion and impaired cell-mediated immunity with subsequent secondary opportunistic infections and increased risk of malignancy. B-cell function is also reduced as a result of lack of T-cell stimulation.
HIV is not a notifiable disease. -
This question is part of the following fields:
- Microbiology
- Principles
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Question 15
Correct
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A 29 year old patient with known inflammatory bowel disease presents to ED with surgical complications following his recent ileocaecal resection. Removal of the terminal ileum may result in the malabsorption of which of the following:
Your Answer: Vitamin B12
Explanation:On ingestion, vitamin B12 is bound to R protein found in saliva and gastric secretions, which protects it from digestion in the stomach. Intrinsic factor is secreted by gastric parietal cells. Receptors for the IF-B12 complex are present in the membrane of epithelial cells of the terminal ileum, which bind the complex and allow uptake of vitamin B12 across the apical membrane by endocytosis. Vitamin B12 is then transported across the basal membrane into the portal blood where it is bound to transcobalamin II and processed by the liver. In pernicious anaemia, there are autoantibodies against gastric parietal cells and intrinsic factor, resulting in vitamin B12 deficiency anaemia.
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This question is part of the following fields:
- Gastrointestinal
- Physiology
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Question 16
Correct
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Which among the following antibacterial regimens is considered the most appropriate to prescribe in a patient presenting with clinical signs and symptoms consistent with a diagnosis of pelvic inflammatory disease?
Your Answer: Ceftriaxone plus doxycycline plus metronidazole
Explanation:The endocervix is the most common site of Neisseria gonorrhoeae infection in women. Symptoms of infection, when present, include dysuria, cervical discharge, and lower abdominal pain. However, 50% of cases in women may be asymptomatic leading to complications such as pelvic inflammatory disease (PID), which may cause sterility, ectopic pregnancy, or perihepatitis.
PID is also known as Fitz-Hugh-Curtis syndrome is defined as an inflammation of the upper genital tract due to an infection in women. The disease affects the uterus, fallopian tubes, and ovaries. It is typically an ascending infection, spreading from the lower genital tract.
The recommended intramuscular or oral regimens for PID are as follows:
Ceftriaxone at 500 mg IM in a single dose (for persons weighing ≥150 kg, administer 1 g of ceftriaxone); plus doxycycline at 100 mg PO BID for 14 days with metronidazole at 500 mg PO BID for 14 days.
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This question is part of the following fields:
- Microbiology
- Specific Pathogen Groups
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Question 17
Correct
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Regarding carbon dioxide transport in the blood, which of the following statements is CORRECT:
Your Answer: Deoxygenated haemoglobin acts as a buffer for H+ ions.
Explanation:CO2generated in the tissues and water combine to form carbonic acid which readily dissociates to form HCO3-and H+. The first part of this reaction is very slow in plasma, but is accelerated dramatically by the enzyme carbonic anhydrase present in red blood cells. Bicarbonate is therefore formed preferentially in red cells, from which it freely diffuses down its concentration gradient into plasma where it is transported to the lungs. The red cell membrane is impermeable to H+ions which remain in the cell. To maintain electroneutrality, Cl-ions diffuse into the cell to replace HCO3-, an effect known as the chloride shift. Deoxygenated haemoglobin acts as a buffer for H+, allowing the reaction to continue.
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This question is part of the following fields:
- Physiology
- Respiratory
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Question 18
Correct
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Which of the following increases the tendency for oedema to occur?
Your Answer: Increased venous pressure
Explanation:When more fluid is filtered out of the capillaries than can be returned to the circulation by the lymphatics, oedema occurs. Changes that increase capillary hydrostatic pressure or decrease plasma oncotic pressure will increase filtration.
Arteriolar constriction reduces hydrostatic capillary pressure and transiently increase absorption of fluid.
Dehydration increases plasma protein concentration and therefore increases plasma oncotic pressure and absorption. Capillary hydrostatic pressure and filtration are increased when there is increased venous pressure. -
This question is part of the following fields:
- Cardiovascular
- Physiology
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Question 19
Correct
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Which of the following is an ECG change typically associated with hyperkalaemia:
Your Answer: Wide QRS complex
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
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Question 20
Correct
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Elevation of the mandible is produced primarily by which of the following muscles:
Your Answer: Temporalis, masseter and medial pterygoid
Explanation:Elevation of the mandible is generated by the temporalis, masseter and medial pterygoid muscles.
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This question is part of the following fields:
- Anatomy
- Head And Neck
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Question 21
Correct
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Liquefactive necrosis is most commonly seen in which of the following conditions:
Your Answer: Ischaemic stroke
Explanation:Liquefactive necrosis results in the loss of all cellular structure and the formation of a soft, semi-solid mass. This is commonly seen in the brain after a cerebral infarction.
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This question is part of the following fields:
- Inflammatory Responses
- Pathology
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Question 22
Correct
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An analytical study is conducted to compare the risk of stroke between Ticagrelor therapy and Warfarin therapy among patients with atrial fibrillation. The following is obtained from the study:
No. of patients who took Ticagrelor: 300
No. of patients who took Ticagrelor and suffered a stroke: 30
No. of patients who took Warfarin: 500
No. of patients who took Warfarin and suffered a stroke: 20
Compute for the risk ratio of a stroke.Your Answer: 2.5
Explanation:Relative risk (RR) is a ratio of the probability of an event occurring in the exposed group versus the probability of the event occurring in the non-exposed group.
RR can be computed as the absolute risk of events in the treatment group (ART), divided by the absolute risk of events in the control group (ARC).
RR = ART/ARC
RR = (30/300) / (20/500)
RR = 2.5Recall that:
If RR < 1, then the intervention reduces the risk of the outcome.
If RR = 1, then the treatment has no effect on the outcome.
If RR > 1, then the intervention increases the risk of the outcome. -
This question is part of the following fields:
- Evidence Based Medicine
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Question 23
Correct
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A 45-year-old African American male presents to your clinic complaining of swelling of his feet for the past six months. On examination, there is periorbital and pedal oedema. A 24-hour urine collection is ordered, which shows 8 g of protein. The serum cholesterol is ten mmol/L. You order a renal biopsy to confirm the diagnosis.
Which one of the following findings are you most likely to see in this patient's biopsy?Your Answer: Focal segmental glomerulosclerosis
Explanation:This patient has Nephrotic Syndrome confirmed by the presence of 1. Heavy proteinuria (greater than 3-3.5 g/24 hours)
2. Hypoalbuminemia (serum albumin < 25 g/L)
3. Generalised oedema (often with periorbital involvement)
4. Severe hyperlipidaemia (total cholesterol is often > 10 mmol/L).Focal Segmental Glomerulosclerosis will be the most likely answer as it is the most common cause of Nephrotic Syndrome in African American adults.
Minimal change disease is the most common cause of nephrotic syndrome in children.
Membranous glomerulonephritis is the most common cause of Nephrotic Syndrome in Caucasian adults.
In IgA nephropathy, patients will complain of cola-coloured urine.
Mesangiocapillary glomerulonephritis presents with features of Nephritic Syndrome.
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This question is part of the following fields:
- General Pathology
- Pathology
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Question 24
Incorrect
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What is the interquartile range of the following data set: 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 60, 70
Your Answer: 20
Correct Answer: 30
Explanation:5, 10, 15 /20, 25, 30 /35, 40, 45 /50, 60, 70
Sample size (n) = 12
Median = [(n+1)/2]th value
= (12+1)/2 = 6.5
= halfway between 6th and 7th value
= (30 +35)/2 = 32.5
The lower (first) quartile = halfway between 15 and 20
= 17.5
The upper (third) quartile = halfway between 45 and 50
= 47.5
The interquartile range is the difference between the upper quartile and lower quartile
= 47.5 – 17.5 = 30 -
This question is part of the following fields:
- Evidence Based Medicine
- Statistics
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Question 25
Incorrect
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What kind of function loss do you anticipate in a 22-year-old guy who had a laceration to his arm, resulting in nerve damage in the antecubital fossa?
Your Answer: Adduction of thumb
Correct Answer: Opposition of thumb
Explanation:The symptoms of median nerve injury include tingling or numbness in the forearm, thumb, and three adjacent fingers, as well as gripping weakness and the inability to move the thumb across the palm.
Because the thenar muscles and the flexor pollicis longus are paralyzed, flexion, abduction, and opposition of the thumb at the MCPJ and IPJ are gone.
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This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 26
Correct
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You see a 30-year-old man who has come to the department with a very tender right elbow. On examination, the elbow is very hot and red, and appears to be acutely inflamed.
Which SINGLE statement regarding acute inflammation is FALSE?Your Answer: Reduced extravascular osmotic pressure leads to oedema
Explanation:Inflammation can be divided intoacute inflammation, which occurs over seconds, minutes, hours, and days, andchronic inflammation, which occurs over longer periods.
Acute inflammationcommences within seconds or minutes following the injury of tissues. There are numerous potential stimuli for an acute inflammatory response including infections (bacterial, viral, fungal, parasitic), tissue necrosis, foreign bodies, and Immune reactions (hypersensitivity reactions). The chief cell type of acute inflammation is the neutrophil.
There are three main processesthat occur in the acute inflammatory response:
Increased blood flow
Increased capillary permeability
Neutrophil migration
1. Increased blood flow:
Vasoactive mediators are released, such as nitric oxide, histamine, bradykinins, and prostaglandin E2. These mediators cause vasodilatation and increased blood flow to the area (causing redness and heat).
2. Increased capillary permeability:
The vasoactive mediators also cause increased capillary permeability by causing endothelial cell contraction that widens the intercellular gaps of venules. This allows an outpouring of protein-rich fluid (exudate) into the extracellular tissues that results in a reduction of intravascular osmotic pressure and an increase in extravascular/interstitial pressure. The increased interstitial osmotic pressure leads to oedema.
3. Neutrophil migration:
Neutrophils leave the vasculature through the following sequence of events:
Margination and rolling: neutrophils flow nearer the vessel wall, rather than in the axial stream, which is referred to as margination. Following margination the neutrophils begin rolling along the surface of the vascular endothelium.
Activation and adhesion: then as a result of interaction with endothelial cell adhesion molecules (CAMs) that is mediated by selectins, the neutrophils are activated and adhere to the endothelium.
Transmigration: once bound to the endothelium, neutrophils squeeze through gaps between adjacent endothelial cells into the interstitial fluid, in a process calleddiapedesis. -
This question is part of the following fields:
- General Pathology
- Pathology
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Question 27
Incorrect
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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: Angina
Correct 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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Question 28
Incorrect
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You want to give colchicine to a patient who has acute gout. Which of the following is a contraindication to the use of colchicine?
Your Answer: Anticoagulant therapy
Correct Answer: Blood dyscrasias
Explanation:Colchicine is used to prevent or treat gout attacks (flares). It works by reducing swelling and the development of uric acid crystals, which cause pain in the affected joint(s).
Colchicine should be avoided by patients who have blood dyscrasias or bone marrow disorders.
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This question is part of the following fields:
- Musculoskeletal
- Pharmacology
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Question 29
Incorrect
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A 25-year-old footballer develops pain and stiffness in his thigh. A diagnosis of iliopsoas syndrome is made.
Iliacus is innervated by which of the following nerves? Select ONE answer only.Your Answer: Superior gluteal nerve
Correct Answer: Femoral nerve
Explanation:Iliacus is innervated by the femoral nerve.
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This question is part of the following fields:
- Anatomy
- Lower Limb
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Question 30
Incorrect
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By what mechanism does Vibrio cholerae causes diarrhoea?
Your Answer: Increases HCO3- secretory channels in intestinal epithelial cells
Correct Answer: Increases Cl- secretory channels in crypt cells
Explanation:Cholera is a severe diarrheal illness caused by the Vibrio cholerae bacteria infecting the bowel. Ingesting cholera-infected food or drink is the a way to contract the disease. In the intestinal crypt cells, the toxigenic bacterium Vibrio cholera activates adenylate cyclase and raises cyclic adenosine monophosphate (cAMP).
cAMP stimulates the Cl-secretory channels in crypt cells, resulting in the secretion of chloride with sodium ions and water. The toxin it produces causes the body to secrete massive amounts of water, resulting in diarrhoea and significant fluid and electrolyte loss.
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This question is part of the following fields:
- Gastrointestinal
- Physiology
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Question 31
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 32
Incorrect
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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: Posterior spinal artery
Correct 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.
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This question is part of the following fields:
- Anatomy
- Central Nervous System
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Question 33
Incorrect
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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 abduction
Correct 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 34
Incorrect
-
Which of the following is required for vitamin B12 absorption:
Your Answer: Pancreatic polypeptide
Correct Answer: Intrinsic factor
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 35
Incorrect
-
A 39-year-old woman's son with meningococcal meningitis was recently admitted to the Paediatric Intensive Care Unit. She is currently 22 weeks pregnant and is concerned about the possibility of her also contracting the disease as she cared closely for her son during his admission.
Which antibiotic would be the MOST appropriate choice for chemoprophylaxis in this case?
Your Answer: Chloramphenicol
Correct Answer: Ciprofloxacin
Explanation:Ciprofloxacin is recommended for use as meningococcal chemoprophylaxis in all age groups and in pregnancy, and is the most appropriate for this patient.
However, rifampicin is the drug of choice for meningococcal chemoprophylaxis because it is licensed for chemoprophylaxis, but multiple doses are necessary and it is not readily available in community pharmacies. It also interacts with oral contraceptives.
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This question is part of the following fields:
- Microbiology
- Specific Pathogen Groups
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Question 36
Correct
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A patient is referred for lung function tests on account of a history of breathlessness and cough.
Which statement about lung volumes is correct?
Your Answer: The tidal volume is the volume of air drawn in and out of the lungs during normal breathing
Explanation:The tidal volume(TV) is the amount of air that moves in and out of the lungs with each respiratory cycle. In a healthy male, the usual volume is 0.5 L (,7 ml/kg body mass).
The vital capacity(VC) is the maximum amount of air that can be exhaled following maximal inspiration. The usual volume in a healthy male is 4.5 L.
The residual volume(RV) is the amount of air remaining in the lungs after maximum expiration. The usual volume in a healthy male is 1.0 L.
The inspiratory reserve volume(IRV) is the maximum amount of air that can be breathed in forcibly after normal inspiration. The usual volume in a healthy male is 3.0 L.
The expiratory reserve volume(ERV) is the volume of air that can be breathed out forcibly after normal expiration. The usual volume in a healthy male is 1.0 L.
Total lung capacity(TLC) is the volume of air the lungs can accommodate. TLC = RV+VC. The usual volume in a healthy male is 5.5 L.
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This question is part of the following fields:
- Physiology
- Respiratory Physiology
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Question 37
Incorrect
-
A 40-year-old man who has a history of asthma arrives at the emergency department complaining of palpitations that have been going on for 5 days. Which of the following beta-blockers is the safest for an asthmatic patient?
Your Answer: Propranolol
Correct Answer: Atenolol
Explanation:Atenolol is a beta blocker, which is a type of medication that works by preventing certain natural substances in the body, such as epinephrine, from acting on the heart and blood vessels.
This effect reduces heart rate, blood pressure, and cardiac strain. Atenolol, bisoprolol fumarate, metoprolol tartrate, nebivolol, and (to a lesser extent) acebutolol have a lower action on beta2 (bronchial) receptors and are thus cardio selective but not cardiac specific.
They have a lower effect on airway resistance, although they are not without this adverse effect.
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This question is part of the following fields:
- Cardiovascular
- Pharmacology
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Question 38
Incorrect
-
A 50-year-old woman has an anaphylactic reaction following accidental ingestion peanuts at a restaurant. She is a known hypertensive on atenolol 50 mg daily and BP is well controlled. She is also on amlodipine 5 mg daily. Two doses of IM adrenaline has been given without improvement.
Which medication may prove helpful in this patient?
Your Answer: PO Tranexamic acid
Correct Answer: IM Glucagon
Explanation:Resistant to the effects of adrenaline in anaphylaxis is seen in patients taking beta-blockers.
Glucagon can be used to overcome the effects of the beta-blockade if initial doses of adrenaline are unsuccessful in patients taking beta-blockers.
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This question is part of the following fields:
- Pharmacology
- Respiratory Pharmacology
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Question 39
Incorrect
-
A 60-year-old female with a past history of rheumatic fever and a prosthetic mitral valve presents to you with fever and an episode of expressive dysphasia that lasted around 30 minutes. There is no history of known drug allergies On examination you note a systolic murmur and you suspect it is infective endocarditis.
Which antibacterial agents would be the most appropriate to prescribe in this case?
Your Answer: Flucloxacillin and gentamicin
Correct Answer: Vancomycin, rifampicin and gentamicin
Explanation:Endocarditis is infective or non infective inflammation (marantic endocarditis) of the inner layer of the heart and it often involves the heart valves.
Risk factors include:
Prosthetic heart valves
Congenital heart defects
Prior history of endocarditis
Rheumatic fever
Illicit intravenous drug useIn the presentation of endocarditis, the following triad is often quoted:
Persistent fever
Embolic phenomena
New or changing murmurA combination of vancomycin, rifampicin and gentamicin is advised if the patient has a cardiac prostheses, is penicillin allergic, or if methicillin-resistant Staphylococcus aureus (MRSA) is suspected. In this case the patient has a prosthetic valve making this the most appropriate initial treatment regimen.
Flucloxacillin and gentamicin are current recommended by NICE and the BNF for the initial ‘blind’ therapy in endocarditis. This patient has prostheses and this is not the most appropriate initial treatment regimen.
Other features that may be present include heart failure, splenomegaly, finger clubbing, renal features (haematuria, proteinuria, nephritis), and vasculitic features (splinter haemorrhages, Osler’s nodes, Janeway lesions, Roth’s spots).
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This question is part of the following fields:
- Microbiology
- Specific Pathogen Groups
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Question 40
Correct
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Which of the following statements is correct with regards to immunoglobulin?
Your Answer: The isotype of immunoglobulin is determined by the heavy chain.
Explanation:The composition of immunoglobulin molecules is two identical heavy and two identical light chains. These chains are linked by disulphide bridges and are each have highly variable regions which give the immunoglobulin its specificity. In addition, they have constant regions and there is virtual complete correspondence in amino acid sequence in all antibodies of a given isotype.
Five isotypes of immunoglobulin exist – these are IgG, IgA, IgM, IgE and IgD. They are determined by the heavy chain (gamma, alpha, mu, epsilon or delta respectively). The light chains are either kappa or lambda. -
This question is part of the following fields:
- Immune Responses
- Pathology
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Question 41
Incorrect
-
One of the following pathogens is a conditional pathogen:
Your Answer: Mycobacterium tuberculosis
Correct Answer: Neisseria meningitidis
Explanation:Obligate pathogens include Mycobacterium TB, HIV, Treponema pallidum, and Neisseria gonorrhoeae. Neisseria meningitidis, on the other hand, is a conditional pathogen.
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This question is part of the following fields:
- Microbiology
- Principles
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Question 42
Incorrect
-
During anaerobic respiration, what is the net generation of ATP molecules:
Your Answer: 8
Correct Answer: 2
Explanation:In anaerobic respiration, two ATP molecules are produced for every glucose molecule, as opposed to the 38 molecules of ATP produced in aerobic respiration.
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This question is part of the following fields:
- Basic Cellular
- Physiology
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Question 43
Incorrect
-
A novel anti-tuberculosis medicine was compared to standard treatment and shown to cut the risk of death from 30 to 10 per 1000 people. How many patients would need to be treated (number need to treat (NNT)) in order to prevent 10 additional tuberculosis deaths:
Your Answer: 100
Correct Answer: 500
Explanation:The risk of mortality in the control group (usual therapy) minus the risk of death in the treatment group equals the absolute risk reduction (ARR) of treatment.
30/1000 minus 10/1000 = 20/1000 = 0.02NNT = 1/ARR = 1/0.02 = 50
As a result, 50 people would need to be treated in order to prevent one additional fatality, and 500 people would need to be treated in order to avoid 10 additional deaths. -
This question is part of the following fields:
- Evidence Based Medicine
- Statistics
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Question 44
Incorrect
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A 7-days-old neonate is taken to the emergency department. She's pyretic, lethargic, and unresponsive, and her fontanelle has bulged. Antibiotics are started, and a lumbar puncture reveals Gram-negative rods. Which pathogen is most likely to be the cause:
Your Answer: Neisseria meningitidis
Correct Answer: Escherichia coli
Explanation:Among neonates, group B streptococci (GBS) are the most commonly identified causes of bacterial meningitis, implicated in roughly 50% of all cases. Escherichia coli(Gram-negative rods) accounts for another 20%. Thus, the identification and treatment of maternal genitourinary infections is an important prevention strategy.
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This question is part of the following fields:
- Infections
- Microbiology
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Question 45
Incorrect
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When a person changes from a supine to an upright position, which of the followingcompensatory mechanismsoccurs:
Your Answer: Decreased total peripheral resistance (TPR)
Correct Answer: Increased contractility
Explanation:On standing from a prone position, gravity causes blood to pool in veins in the legs. Central venous pressure (CVP) falls, causing a fall in stroke volume and cardiac output (due to Starling’s law) and thus a fall in blood pressure. Normally this fall in BP is rapidly corrected by the baroreceptor reflex which causes venoconstriction (partially restoring CVP), and an increase in heart rate and contractility, so restoring cardiac output and blood pressure. Impaired autonomic nervous activity in the elderly accounts for the greater likelihood of postural hypotension. Any symptoms of dizziness, blurred vision or syncope is due to a transient fall in cerebral perfusion that occurs before cardiac output and mean arterial pressure (MAP) can be corrected.
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This question is part of the following fields:
- Cardiovascular
- Physiology
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Question 46
Incorrect
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Regarding the management of gout, which of the following statements is CORRECT:
Your Answer: Colchicine is used as a long term therapy for prevention of gout.
Correct Answer: Allopurinol may cause an acute attack of gout when first started.
Explanation:Allopurinol is a treatment for the prevention of gout. The initiation of treatment may precipitate an acute attack, and should be covered with an NSAID or colchicine, continued for at least one month after the hyperuricaemia has been corrected. Colchicine is not indicated for long term prevention of gout. NSAIDs are first line for acute gout; colchicine is an alternative in whom NSAIDs are contraindicated, not tolerated or ineffective (including in people taking anticoagulants). Ibuprofen is not recommended for acute gout, given it has only weak anti-inflammatory properties; naproxen, diclofenac or indometacin are indicated instead.
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This question is part of the following fields:
- Musculoskeletal
- Pharmacology
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Question 47
Incorrect
-
C3 deficiency leads to particular susceptibility of infection with which of the following:
Your Answer: Intracellular bacteria
Correct Answer: Encapsulated bacteria
Explanation:Macrophages and neutrophils have C3b receptors and they phagocytose C3b-coated cells. C3 deficiency thus leads to increased susceptibility of infection with encapsulated organisms (e.g. S. pneumoniae, H. influenzae).The early stages of the complement cascade leading to coating of the cells with C3b can occur by two different pathways:The classical pathway usually activated by IgG or IgM coating of cellsThe alternative pathway which is more rapid and activated by IgA, endotoxin and other factors
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This question is part of the following fields:
- Immune Responses
- Pathology
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Question 48
Correct
-
Reed-Sternberg cells are characteristic of which of the following malignancies:
Your Answer: Hodgkin lymphoma
Explanation:Lymphomas are a group of diseases caused by malignant lymphocytes that accumulate in lymph nodes and other lymphoid tissue and cause the characteristic clinical feature of lymphadenopathy. The major subdivision of lymphomas is into Hodgkin lymphoma (HL) and non-Hodgkin lymphoma (NHL) and this is based on the histological presence of Reed-Sternberg cells present in HL. Hodgkin lymphoma can present at any age but is rare in children and has a peak incidence in young adults. There is an almost 2 : 1 male predominance. Most patients present with painless, asymmetrical, firm and discrete enlargement of superficial lymph nodes. Cervical nodes are involved in 60-70% of cases, axillary nodes in 10-15% and inguinal nodes in 6-12%. Modest splenomegaly occurs during the course of the disease in 50% of patients; the liver may also be enlarged. Bone marrow failure involvement is unusual in early disease. The prognosis depends on age, stage and histology, but overall approximately 85% of patients are cured. Alcohol‐induced pain and pruritus are two well‐known but rare symptoms in HL.
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This question is part of the following fields:
- Haematology
- Pathology
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Question 49
Incorrect
-
Blood flows from the left atrium into the left ventricle via:
Your Answer: The tricuspid valve
Correct Answer: The mitral valve
Explanation:Blood flows from the right atrium into the right ventricle via the tricuspid atrioventricular valve and from the left atrium into the left ventricle via the mitral atrioventricular valve. Blood is ejected from the right ventricle through the pulmonary semilunar valve into the pulmonary artery and from the left ventricle via the aortic semilunar valve into the aorta.
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This question is part of the following fields:
- Cardiovascular
- Physiology
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Question 50
Incorrect
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All of the following statements are correct regarding the management of acute asthma in adults except:
Your Answer: Nebulised magnesium is not recommended for treatment in adults with acute asthma.
Correct Answer: Intravenous aminophylline has been shown to result in significant additional bronchodilation compared to standard care.
Explanation:There usually isn’t any additional bronchodilation with intravenous (IV) aminophylline compared to standard care with inhaled bronchodilators and steroids. IV aminophylline may cause side effects such as arrhythmias and vomiting. However, some additional benefit may be gained in patients with near-fatal asthma or life-threatening asthma with a poor response to initial therapy (5 mg/kg loading dose over 20 minutes unless on maintenance oral therapy, then continuous infusion of 0.5 – 0.7 mg/kg/hr).
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This question is part of the following fields:
- Pharmacology
- Respiratory
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Question 51
Incorrect
-
A 39-year-old man with a long history of depression presents after intentionally overdoing his heart medication. Verapamil immediate-release 240 mg is the tablet he takes for this condition, he says. He took the pills about 30 minutes ago, but his wife discovered him right away and rushed him to the emergency room.
At the moment, he is completely symptom-free. When it comes to this type of overdose, how long does it usually take for symptoms to appear?Your Answer: 12-16 hours
Correct Answer: 1-2 hours
Explanation:Overdosing on calcium-channel blockers should always be taken seriously and regarded as potentially fatal. Verapamil and diltiazem are the two most lethal calcium channel blockers in overdose. These work by binding the alpha-1 subunit of L-type calcium channels, preventing calcium from entering the cell. In cardiac myocytes, vascular smooth muscle cells, and islet beta-cells, these channels play an important role.
>10 tablets of verapamil (160 mg or 240 mg immediate or sustained-release capsules) or diltiazem can cause serious toxicity (180 mg, 240 mg or 360 mg immediate or sustained-release capsules)
In children, 1-2 tablets of verapamil or diltiazem (immediate or sustained-release)
Symptoms usually appear within 1-2 hours of ingestion with standard preparations. However, with slow-release preparations, significant toxicity may take 12-16 hours to manifest, with peak effects occurring after 24 hours.
The following are the main clinical features of calcium-channel blocker overdose:
Nausea and vomiting
Hypotension
Bradycardia and first-degree heart block
Myocardial ischaemia and stroke
Renal failure
Pulmonary oedema
HyperglycaemiaThe following are some of the most important bedside investigations to conduct:
Blood glucose
ECG
Arterial blood gas
Other investigations that can be helpful include
Urea & electrolytes
Chest X-ray (pulmonary oedema)
Echocardiography -
This question is part of the following fields:
- Cardiovascular Pharmacology
- Pharmacology
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Question 52
Incorrect
-
A 62-year-old woman presents with a 3-month history of lethargy and tiredness. She states that she has also felt very itchy, particularly after a hot bath and that she is often dizzy and sweaty. On examination she appears plethoric and you note the presence of splenomegaly. Her blood tests today show that her haemoglobin level is 16.9 g/dl.
What is the most likely diagnosis in this case? Select ONE answer only.Your Answer: Essential thrombocytosis
Correct Answer: Polycythaemia vera
Explanation:Polycythaemia vera (PCV), which is also referred to as polycythaemia rubra vera, is a clonal haematological malignancy in which the bone marrow produces too many red blood cells. It may also result in the overproduction of white blood cells and platelets. It is most commonly seen in the elderly and the mean age at diagnosis is 65-74 years.
Patients can be completely asymptomatic and it is often discovered as an incidental finding on a routine blood count. Approximately 1/3 of patients present with symptoms due to thrombosis, of these 3/4 have arterial thrombosis and 1/4 venous thrombosis. Features include stroke, myocardial infarction, deep vein thrombosis and pulmonary embolism.
The other clinical features of PCV include:
Plethoric appearance
Lethargy and tiredness
Splenomegaly (common)
Pruritis (in 40% – particularly after exposure to hot water)
Headaches, dizziness and sweating (in 30%)
Gouty arthritis (in 20%)
Budd-Chiari syndrome (in 5-10%)
Erythromyalgia (in <5% – burning pain and red/blue discolouration of hands and feet)
Increased incidence of peptic ulcer disease (possibly related to increased histamine release from mast cells)
The diagnosis of PCV requires two major criteria and one minor criterion, or the first major criterion and two minor criteria:
Major criteria:
HB > 18.5 g/dl in men, 16.5 g/dl in women
Elevated red cell mass > 25% above mean normal predicted value
Presence of JAK2 mutationMinor criteria:
Bone marrow biopsy showing hypercellularity with prominent erythroid, granulocytic and megakaryocytic proliferation
Serum erythropoietin level below normal range
Endogenous erythroid colony formation in vitro
The main aim of treatment is to normalize the full blood count and prevent complications such as thrombosis. Venesection is the treatment of choice but hydroxyurea can also be used to help control thrombocytosis. -
This question is part of the following fields:
- Haematology
- Pathology
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Question 53
Incorrect
-
Gastrin release from antral G-cells is stimulated by all but which one of the following:
Your Answer: Raised gastric pH
Correct 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 54
Correct
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Many of the chemical digestion and absorption takes place in the small intestine. Most digestive enzymes in the small intestine are secreted by the pancreas and enter the small intestine through the pancreatic duct.
Which of these digestive enzymes is responsible for breaking down carbohydrates into monosaccharides?Your Answer: Glucoamylase
Explanation:Majority of carbohydrates are broken down into monosaccharides (glucose, fructose galactose) and are absorbed by the small intestine. Enzymes released from the brush border break down carbohydrate. Some carbohydrates, such as cellulose, are not digested at all, despite being made of multiple glucose units. This is because the cellulose is made out of beta-glucose that makes the inter-monosaccharide bindings different from the ones present in starch, which consists of alpha-glucose. Humans lack the enzyme for splitting the beta-glucose-bond.
The principal brush border enzymes are dextranase and glucoamylase. Other brush border enzymes are maltase, sucrase, and lactase.
Pancreatic amylase breaks down some carbohydrates (notably starch) into oligosaccharides. Dextranase and glucoamylase, then further break down oligosaccharides.
Trypsin aids in digestion of protein.
Chymotrypsin is a proteolytic enzyme that digests protein
Carboxypeptidase hydrolyses the first peptide or amide bond at the carboxyl or C-terminal end of proteins and peptides
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This question is part of the following fields:
- Gastrointestinal Physiology
- Physiology
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Question 55
Incorrect
-
A 27-year-old man was sent to the emergency department by ambulance with suspected anaphylaxis. What is the best first-line treatment for this patient?
Your Answer: 0.5 mg of adrenaline intravenously if access has been achieved
Correct Answer: 500 micrograms of adrenaline intramuscularly
Explanation:Anaphylaxis is the sudden onset of systemic hypersensitivity due to IgE-mediated chemical release from mast cells and basophils.
If anaphylaxis is suspected, 500 micrograms of adrenaline should be administered promptly (0.5 ml of 1:1000 solution).
In anaphylaxis, the intramuscular route is the most immediate approach; the optimal site is the anterolateral aspect of the middle part of the thigh.
Intravenous adrenaline should only be given by people who are well-versed in the use and titration of vasopressors in their routine clinical practice.
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This question is part of the following fields:
- Pharmacology
- Respiratory
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Question 56
Incorrect
-
In a ward round, you come across a patient's treatment chart prescribed an antibiotic to fight his infection. This antibiotic disrupts cell membrane function.
Which of the following antimicrobial drugs is prescribed to this patient?Your Answer: Trimethoprim
Correct Answer: Nystatin
Explanation:Nystatin binds ergosterol (unique to the fungi cell membrane) and forms membrane pores that allow K+ leakage, acidification, and subsequent death of the fungus.
Vancomycin inhibits cell wall peptidoglycan formation by binding the D-Ala-D-Ala portion of cell wall precursors.
Flucloxacillin inhibits the synthesis of bacterial cell walls. It inhibits cross-linkage between the linear peptidoglycan polymer chains that make up a major component of the cell wall of Gram-positive bacteria.
Trimethoprim inhibits bacterial dihydrofolate reductase.
Isoniazid decreases the synthesis of mycolic acids in mycobacteria.
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This question is part of the following fields:
- Infections
- Pharmacology
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Question 57
Incorrect
-
Which of the following acts to inhibit antidiuretic hormone (ADH) release from the posterior pituitary:
Your Answer: Adrenaline
Correct Answer: Atrial natriuretic peptide
Explanation:ADH release is inhibited by low plasma osmolality, alcohol, caffeine, glucocorticoids and atrial natriuretic peptide (ANP).
ADH release is stimulated primarily by raised plasma osmolality detected by osmoreceptors in the anterior hypothalamus. Other factors that increase ADH release include: extracellular fluid volume depletion, angiotensin II, nausea, pain, stress, exercise, emotion, hypoglycaemia.
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This question is part of the following fields:
- Endocrine
- Physiology
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Question 58
Incorrect
-
When treating diabetic ketoacidosis (DKA), glucose should be given together with insulin as soon as the blood glucose concentration falls below 14 mmol/L in the form of:
Your Answer: 5% glucose intravenous infusion at a rate of 125 mL/hour
Correct Answer: 10% glucose intravenous infusion at a rate of 125 mL/hour
Explanation:In addition to the sodium chloride 0.9 percent infusion, glucose 10% should be given intravenously (into a large vein with a large-gauge needle) at a rate of 125 mL/hour once blood glucose concentration falls below 14 mmol/litre.
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This question is part of the following fields:
- Endocrine
- Pharmacology
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Question 59
Incorrect
-
The neurotransmitter in the synaptic cleft is either eliminated or deactivated after the postsynaptic cell responds to the neurotransmitter.
Which of the following enzymes catalyses the breakdown of noradrenaline?Your Answer: Acetylcholinesterase (ACh)
Correct Answer: Catechol-O-methyltransferase (COMT)
Explanation:The neurotransmitter in the synaptic cleft is either eliminated or deactivated after the post-synaptic cell responds to the neurotransmitter.
This can be accomplished in a variety of ways:
Re-uptake
Breakdown
DiffusionSerotonin is an example of a neurotransmitter that is uptake. Serotonin is absorbed back into the presynaptic neuron via the serotonin transporter (SERT), which is found in the presynaptic membrane. Re-uptake neurotransmitters are either recycled by repackaging into vesicles or broken down by enzymes.
Specific enzymes found in the synaptic cleft can also break down neurotransmitters. The following enzymes are examples of these enzymes:
Acetylcholinesterase (AChE) catalyses the acetylcholine breakdown (ACh)
The enzyme catechol-O-methyltransferase (COMT) catalyses the breakdown of catecholamines like adrenaline , dopamine and noradrenaline.The breakdown of catecholamines, as well as other monoamines like serotonin, tyramine, and tryptamine, is catalysed by monoamine oxidases (MOA).
Diffusion of neurotransmitters into nearby locations can also be used to eliminate them. -
This question is part of the following fields:
- Basic Cellular Physiology
- Physiology
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Question 60
Incorrect
-
You are about to give an antimuscarinic agent to a 55 year-old male patient. Which of the following conditions will make you with stop the administration, since it is a contraindication to antimuscarinic agents?
Your Answer: Parkinson disease
Correct Answer: Prostatic enlargement
Explanation:Antimuscarinic medications may impair the contractility of bladder smooth muscle, resulting in acute urine retention in men with BPH, and should be avoided or used with caution.
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This question is part of the following fields:
- Gastrointestinal
- Pharmacology
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Question 61
Incorrect
-
Regarding conduction of nerve impulses, which of the following statements is CORRECT:
Your Answer: Action potentials travel faster in unmyelinated fibres than in myelinated nerve fibres.
Correct Answer: The action potential in myelinated axons is propagated only at the nodes of Ranvier.
Explanation:An action potential is a self-propagating response, successive depolarisation moving along each segment of an unmyelinated nerve until it reaches the end. It is all-or-nothing and does not decrease in size. Conduction in myelinated fibres is much faster, up to 50 times that of the fastest unmyelinated nerve. Myelinated fibres are insulated except at areas devoid of myelin called nodes of Ranvier. The depolarisation jumps from one node of Ranvier to another by a process called saltatory conduction. Saltatory conduction not only increases the velocity of impulse transmission but also conserves energy for the axon because depolarisation only occurs at the nodes and not along the whole length of the nerve fibre. Larger diameter myelinated nerve fibres conduct nerve impulses faster than small unmyelinated nerve fibres.
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This question is part of the following fields:
- Basic Cellular
- Physiology
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Question 62
Incorrect
-
A 24-year-old male presents to the Emergency Department with a three-day history of high-grade fever, headache and rash along with neck stiffness. On examination, Kernig's sign is positive, and you note a petechial rash over the trunk and limbs. Her vital signs show tachycardia and hypotension. Based on these findings, you diagnose sepsis secondary to meningitis.
Which one of the following definitions of sepsis is currently accepted?Your Answer: The presence of > 3 SIRS criteria in the presence of a suspected source of infection
Correct Answer: Life-threatening organ dysfunction caused by a dysregulated host response to infection
Explanation:In 2016 the SOFA guideline was introduced, also called the Sepsis-related Organ Failure Assessment, to make a sepsis diagnosis easier and prevent mortality.
According to this guideline, sepsis was defined as a life-threatening organ dysfunction due to a dysregulated host response to infection.
Septic shock was defined as a subset of sepsis in which the circulatory and metabolic abnormalities would lead to a greater risk of mortality than sepsis alone. Patients with septic shock would be clinically identified by a need for vasopressors to maintain MAP greater than 65 mmHg and serum lactate greater than two mmol/L.
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This question is part of the following fields:
- Pathology
- Pathology Of Infections
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Question 63
Correct
-
Molecules with a molecular weight of less than which of the following are filtered freely at the glomerular filtration barrier:
Your Answer: 7000 Da
Explanation:Molecular weight is the main factor in determining whether a substance is filtered or not – molecules < 7 kDa in molecular weight are filtered freely e.g. glucose, amino acids, urea, ions but larger molecules are increasingly restricted up to 70 kDa, above which filtration is insignificant. Negatively charged molecules are further restricted, as they are repelled by negative charges, particularly in the basement membrane. Albumin has a molecular weight of 69 kDa and is negatively charged, thus only very small amounts are filtered (and all of the filtered albumin is reabsorbed in the proximal tubule), whereas small molecules such as ions, glucose, amino acids and urea pass the filter without hindrance. This means that ultrafiltrate is virtually protein free, but otherwise has an identical composition of that of plasma. The epithelial lining of the Bowman's capsule consists of a single layer of cells called podocytes. The glomerular capillary endothelium is perforated by pores (fenestrations) which allow plasma components with a molecular weight of < 70 kDa to pass freely.
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This question is part of the following fields:
- Physiology
- Renal
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Question 64
Incorrect
-
Alpha cells of the endocrine pancreas produce which of the following hormones:
Your Answer: Pancreatic polypeptide
Correct Answer: Glucagon
Explanation:Glucagon is a peptide hormone that is produced and secreted by alpha cells of the islets of Langerhans, which are located in the endocrine portion of the pancreas. The main physiological role of glucagon is to stimulate hepatic glucose output, thereby leading to increases in glycaemia. It provides the major counter-regulatory mechanism to insulin in maintaining glucose homeostasis.
Hypoglycaemia is the principal stimulus for the secretion of glucagon but may also be used as an antidote in beta-blocker overdose and in anaphylaxis in patients on beta-blockers that fail to respond to adrenaline.
Glucagon then causes:
Glycogenolysis
Gluconeogenesis
Lipolysis in adipose tissue
The secretion of glucagon is also stimulated by:
Adrenaline
Cholecystokinin
Arginine
Alanine
Acetylcholine
The secretion of glucagon is inhibited by:
Insulin
Somatostatin
Increased free fatty acids
Increased urea productionGlycolysis is the metabolic pathway that converts glucose into pyruvate. The free energy released by this process is used to form ATP and NADH. Glycolysis is inhibited by glucagon, and glycolysis and gluconeogenesis are reciprocally regulated so that when one cell pathway is activated, the other is inactive and vice versa.
Glucagon has a minor effect of enhancing lipolysis in adipose tissue. Lipolysis is the breakdown of lipids and involves the hydrolysis of triglycerides into glycerol and free fatty acids. It makes fatty acids available for oxidation.
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This question is part of the following fields:
- Endocrine
- Physiology
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Question 65
Incorrect
-
All of the muscles of the tongue (other than the palatoglossus) are innervated by which of the following nerves:
Your Answer: Glossopharyngeal nerve
Correct Answer: Hypoglossal nerve
Explanation:All of the muscles of the tongue are innervated by the hypoglossal nerve, except for the palatoglossus, which is innervated by the vagus nerve.
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This question is part of the following fields:
- Anatomy
- Head And Neck
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Question 66
Incorrect
-
A 20-year-old male patient lives in a travelling community and has never received any vaccinations. He presents to you with fever.
Which of these statements concerning indications and contraindications for vaccination is TRUE?
Your Answer: Premature infants should not be vaccinated according to the usual immunisation schedule
Correct Answer: Inactivated vaccines are safe in pregnancy
Explanation:All vaccines are contraindicated in individuals with: A confirmed anaphylactic reaction to a previous dose of the vaccine or a vaccine containing the same antigens.
A confirmed anaphylactic reaction to a component in the vaccine e.g. neomycinThere is no evidence that vaccinating pregnant women with inactivated vaccine or toxoids harms the woman or foetus.
The current protocol is that a child with history of egg allergy can be safely vaccinated with Fluenz tetra. However, if they had a previous severe anaphylaxis to egg requiring intensive care, then Flenz tetra is contraindicated.
BCG, yellow fever or oral typhoid vaccinations are not safe in HIV positive patients.
The normal times recommended for immunization of full-term babies should also be applied to premature infants and correction for gestational age should not be implemented.
Concurrent antibiotic therapy is not a contraindication to vaccination.
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This question is part of the following fields:
- Microbiology
- Principles Of Microbiology
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Question 67
Incorrect
-
Red cell protein expression is induced by which of the following pathogens:
Your Answer: HIV
Correct Answer: Plasmodium falciparum
Explanation:Plasmodium falciparum induces the expression of red cell protein, making cerebral malaria more severe. Bacteria may invade a host passively through micro traumata or macro traumata in the skin or mucosa. On the other hand, bacteria that invade
through intact mucosa first, adhere to this anatomical barrier, then actively
breach it. -
This question is part of the following fields:
- Microbiology
- Principles
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Question 68
Incorrect
-
In which part of the gastrointestinal tract is Meckel's diverticulum commonly located?
Your Answer: Jejunum
Correct Answer: Ileum
Explanation:Meckel’s diverticulum is the most prevalent congenital anomaly of the gastrointestinal tract, affecting approximately 2% of the general population. Meckel’s diverticulum are designated true diverticula because their walls contain all the layers found in normal small intestine. Their location varies among individual patients, but they are usually found in the ileum within 100 cm of the ileocecal valve.
Approximately 60% of Meckel’s diverticulum contain heterotopic mucosa, of which over 60% consist of gastric mucosa. Pancreatic acini are the next most common; others include Brunner’s glands, pancreatic islets, colonic mucosa, endometriosis, and hepatobiliary tissues.
A useful, although crude, mnemonic describing Meckel’s diverticulum is the “rule of twos”: 2% prevalence, 2:1 male predominance, location 2 feet proximal to the ileocecal valve in adults, and half of those who are symptomatic are under 2 years of age.
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This question is part of the following fields:
- Abdomen And Pelvis
- Anatomy
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Question 69
Incorrect
-
Excessive gastric acid output is detected in a patient with a history of recurrent stomach ulcers. It's possible that the patient has Zollinger-Ellison syndrome.
Which of the following statements about stomach acid is correct?Your Answer: It is secreted by chief cells
Correct Answer: The proton pump located in the canalicular membrane is vital to its secretion
Explanation:The stomach produces gastric acid, which is a digesting fluid. The stomach secretes about 2-3 litres every day. It is involved in tissue breakdown, the conversion of pepsinogen to active pepsin, and the creation of soluble salts with calcium and iron, and has a pH range of 1.5-3.5. It also serves as an immune system by destroying microbes.
The following substances are found in gastric acid:
Water
Acid hydrochloride
Pepsinogen
mucous
Intrinsic factorThe parietal cells in the proximal 2/3 (body) of the stomach release gastric acid. The concentration of hydrogen ions in parietal cell secretions is 1-2 million times that of blood. Chloride is released against both a concentration and an electric gradient, and active transport is required for the parietal cell to produce acid.
The following is how stomach acid is secreted:
1. Gastric acid secretion is dependent on the H+/K+ ATPase (proton pump) situated in the canalicular membrane. The breakdown of water produces hydrogen ions within the parietal cell. The hydroxyl ions produced in this reaction mix quickly with carbon dioxide to generate bicarbonate ions. Carbonic anhydrase is the enzyme that catalyses this process.
2. In return for chloride, bicarbonate is carried out of the basolateral membrane. The ‘alkaline tide’ occurs when bicarbonate is released into the bloodstream, resulting in a modest rise in blood pH. The parietal cell’s intracellular pH is maintained by this procedure. Conductance channels carry chloride and potassium ions into the lumen of canaliculi.
3. Through the action of the proton pump, hydrogen ions are pushed out of the cell and into the lumen in exchange for potassium; potassium is thus efficiently recycled.
4. The canaliculi accumulate osmotically active hydrogen ions, which creates an osmotic gradient across the membrane, allowing water to diffuse outward.
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This question is part of the following fields:
- Gastrointestinal Physiology
- Physiology
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Question 70
Incorrect
-
Pancreatic acinar digestive enzyme secretion is mainly stimulated by which of the following hormones:
Your Answer: Glucagon
Correct Answer: Cholecystokinin
Explanation:Exocrine pancreatic secretion is controlled by:
Parasympathetic stimulation which enhances secretion of both the enzyme and aqueous components
Sympathetic stimulation which inhibits pancreatic secretion
Secretin which stimulates secretion of the alkaline-rich fluid from ductal cells
Cholecystokinin which stimulates secretion of the enzyme-rich fluid from acinar cells
Somatostatin which inhibits secretion from both acinar and ductal cells
Gastrin which stimulates pancreatic acinar cells to secrete digestive enzymes -
This question is part of the following fields:
- Gastrointestinal
- Physiology
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Question 71
Incorrect
-
A 78-year-old man complains of lumps in his neck. Several large, non-tender cervical lymph nodes are discovered during your examination.
You arrange for some blood tests, and the results reveal that he has lymphocytosis with a count of 16 x 10 9 /l.
In this case, what is the most likely diagnosis?Your Answer: Hodgkin’s lymphoma
Correct Answer: Chronic lymphocytic leukaemia
Explanation:The most common type of adult leukaemia is chronic lymphocytic leukaemia (CLL). It develops as a result of relatively mature lymphocytes clonally proliferating. The B-cell lineage accounts for approximately 95% of cases. CLL is primarily a disease of adult men, with men over the age of 50 accounting for more than 75% of CLL patients.
It is the most indolent form of chronic leukaemia, and it is frequently discovered by chance when blood counts are taken for other reasons, such as ‘well man’ screening tests. The patient may develop lymphadenopathy, hepatosplenomegaly, anaemia, and infections as the disease progresses.
The following are examples of CLL laboratory findings:
Clonal B cell lymphocytosis (diagnosed at greater than 5 x 109/l, but can reach 300 x 109/l)
In advanced disease, normocytic, normochromic anaemia is present.Patients with autoimmune-related haemolytic anaemias have a positive direct antiglobulin test (DAT).
Although bone marrow aspiration is not always required, it can aid in the diagnosis of CLL. If there has been rapid lymph node enlargement, a lymph node biopsy is required to rule out Richter’s syndrome. This is the transition from low-grade lymphoma to high-grade lymphoma, which is characterised by fever, weight loss, and pain.
Although there is no cure for CLL, it can be managed with chemotherapy regimens that help patients live longer. Early treatment has no benefit, and the standard treatment for early disease is to watch and wait, with examinations and blood counts every 3 to 12 months. Chemotherapy is usually reserved for patients who have a disease that is active and causing symptoms.
The following is the overall prognosis for CLL:
1/3 will not require treatment and will live a long time.
1/3 will go through an indolent phase before the disease progresses.
1/3 of patients will have an aggressive disease that requires immediate treatment. -
This question is part of the following fields:
- Haematology
- Pathology
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Question 72
Correct
-
Regarding cortical areas, which one is found in the posterior part of the inferior frontal gyrus?
Your Answer: Broca’s area
Explanation:Broca’s area is involved in the expressive aspects of spoken and written language (production of sentences constrained by the rules of grammar and syntax). It corresponds to the opercular and triangular parts of the inferior frontal gyrus (BA 44 and 45). These areas are defined by two rami (branches) of the lateral sulcus (one ascending, one horizontal) which ‘slice into’ the inferior frontal gyrus. In keeping with its role in speech and language, Broca’s area is immediately anterior to the motor and premotor representations of the face, tongue and larynx. A homologous area in the opposite hemisphere is involved in non-verbal communication such as facial expression, gesticulation and modulation of the rate, rhythm and intonation of speech.
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This question is part of the following fields:
- Anatomy
- Central Nervous System
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Question 73
Incorrect
-
You are about to perform an emergency pericardiocentesis on a 26-year-old male who was involved in a car accident and is suspected of having cardiac tamponade due to signs of hypotension, muffled heart sounds, and distended neck veins. Where should you insert the needle to relieve tamponade?
Your Answer: Right fifth intercostal space midclavicular line
Correct Answer: Inferior and to the left of the xiphochondral junction
Explanation:Pericardiocentesis is a procedure that removes excess fluid from the pericardium. As a result, it’s used in cases of cardiac tamponade, which occurs when there’s too much fluid in the space around the heart.
During the procedure, a needle and a small catheter are inserted 1 to 2 cm inferior and to the left of the xiphochondral junction into the pericardial cavity.
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This question is part of the following fields:
- Anatomy
- Thorax
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Question 74
Incorrect
-
A 61-year-old patient experiences a spontaneous rupture of his Achilles tendon following a course of antibiotics
Which of the antibiotics listed below is MOST likely to be the cause?Your Answer: Co-amoxiclav
Correct Answer: Ciprofloxacin
Explanation:Tendinopathy and spontaneous tendon rupture are caused by fluoroquinolones, which are an uncommon but well-known cause. Tendon problems caused by fluoroquinolones are expected to affect 15 to 20 people per 100,000. Patients over the age of 60 are most likely to develop them.
It usually affects the Achilles tendon, but it has also been described in cases involving the quadriceps, peroneus brevis, extensor pollicis longus, long head of biceps brachii, and rotator cuff tendons. The exact aetiology is uncertain, although the fluoroquinolone medication is thought to obstruct collagen activity and/or cut off blood supply to the tendon.
Other factors linked to tendon rupture spontaneously include:
Gout
Treatment with corticosteroids
Hypercholesterolaemia
Long-term dialysis
Kidney transplant
Rheumatoid arthritis -
This question is part of the following fields:
- Infections
- Pharmacology
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Question 75
Incorrect
-
You examine a 79-year-old woman who has had hypertension and atrial fibrillation in the past. Her most recent blood tests show that she has severe renal impairment.
Which medication adjustments should you make in this patient's case?Your Answer: Stop aspirin
Correct Answer: Reduce dose of digoxin
Explanation:Digoxin is excreted through the kidneys, and impaired renal function can lead to elevated digoxin levels and toxicity.
The patient’s digoxin dose should be reduced in this case, and their digoxin level and electrolytes should be closely monitored. -
This question is part of the following fields:
- Cardiovascular Pharmacology
- Pharmacology
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Question 76
Incorrect
-
For the treatment of his atrial fibrillation, a 59-year-old man is about to begin taking warfarin. He also takes a number of other medications.
Which of the following medications will enhance warfarin's effects?Your Answer: Carbamazepine
Correct Answer: Erythromycin
Explanation:Many medications, including warfarin, require cytochrome P450 enzymes for their metabolism. When co-prescribing cytochrome p450 enzyme inducers and inhibitors with warfarin, it’s critical to be cautious.
Inhibitors of the cytochrome p450 enzyme potentiate the effects of warfarin, resulting in a higher INR. To remember the most commonly encountered cytochrome p450 enzyme inhibitors, use the mnemonic O DEVICES:
O– Omeprazole
D– Disulfiram
E– Erythromycin (And other macrolide antibiotics)
V– Valproate (sodium valproate)
I– Isoniazid
C– Ciprofloxacin
E– Ethanol (acute ingestion)
S- Sulphonamides -
This question is part of the following fields:
- Cardiovascular Pharmacology
- Pharmacology
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Question 77
Incorrect
-
Which of the following drugs used in the management of hyperkalaemia does not affect serum potassium levels:
Your Answer: Salbutamol
Correct Answer: Calcium gluconate
Explanation:Calcium gluconate is given to antagonise cardiac cell membrane excitability to reduce the risk of arrhythmias. It has no effect on serum potassium levels unlike the alternative drugs listed above.
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This question is part of the following fields:
- Fluids And Electrolytes
- Pharmacology
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Question 78
Correct
-
A 78-year-old male presents to the Orthopaedic clinic with lower back pain for the past month. His past medical history reveals a history of cancer. After examination, you diagnose Metastatic Spinal Cord Compression (MSCC).
Which one of the following cancers is this patient most likely to have had?Your Answer: Prostate cancer
Explanation:Compression of the thecal sac causes metastatic Spinal Cord Compression (MSCC) due to a Metastatic tumour and its components. It can cause symptoms of limb weakness, sensory disturbances and back pain depending on the extent and level of Compression.
The most common source of a tumour causing MSCC is a prostate carcinoma that metastasized to the spinal cord via the vertebral venous plexus.
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This question is part of the following fields:
- General Pathology
- Pathology
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Question 79
Incorrect
-
Regarding ACE inhibitors, which of the following statements is CORRECT:
Your Answer: They are recommended first line treatment for hypertension in patients of Afro-Caribbean descent.
Correct Answer: Angiotensin-II receptor blockers are a useful alternative in patients who cannot tolerate ACE-inhibitors due a persistent cough.
Explanation:ACE inhibitors should be used with caution in patients of Afro-Caribbean descent who may respond less well; calcium channel blockers are first line for hypertension in these patients. ACE inhibitors have a role in the management of diabetic nephropathy. ACE inhibitors are contraindicated in pregnant women. ACE inhibitors inhibit the breakdown of bradykinin; this is the cause of the persistent dry cough. Blocking ACE also diminishes the breakdown of the potent vasodilator bradykinin which is the cause of the persistent dry cough. Angiotensin-II receptor blockers do not have this effect, therefore they are useful alternative for patients who have to discontinue an ACE inhibitor because of persistent cough.
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This question is part of the following fields:
- Cardiovascular
- Pharmacology
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Question 80
Incorrect
-
Question 81
Incorrect
-
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: Midazolam
Correct 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 82
Incorrect
-
Which of the following is NOT a typical effect of cortisol:
Your Answer: Increased glycolysis
Correct Answer: Decreased protein catabolism
Explanation:Cortisol is a steroid hormone produced in the zona fasciculata of the adrenal cortex. It is released in response to stress and low blood glucose concentrations.
Cortisol acts to: raise plasma glucose by stimulating glycolysis and gluconeogenesis in the liver and inhibiting peripheral glucose uptake into storage tissues, increase protein breakdown in skeletal muscle, skin and bone to release amino acids, increase lipolysis from adipose tissues to release fatty acidsand at higher levels and mimic the actions of aldosterone on the kidney to retain Na+ and water and lose K+ ionssuppress the action of immune cells -
This question is part of the following fields:
- Endocrine
- Physiology
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Question 83
Incorrect
-
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 84
Incorrect
-
A 70-year-old patient is diagnosed with Cushing's disease. She has a history of weight gain, hypertension, and easy bruising.
In this patient, which of the following is the MOST LIKELY UNDERLYING CAUSE?Your Answer: Ectopic corticotropin syndrome
Correct Answer: Pituitary adenoma
Explanation:Cushing’s syndrome is a collection of symptoms and signs caused by prolonged exposure to elevated levels of either endogenous or exogenous glucocorticoids.
The most common cause of Cushing’s syndrome is the iatrogenic administration of corticosteroids. The second most common cause of Cushing’s syndrome is Cushing’s disease.
Cushing’s disease should be distinguished from Cushing’s syndrome and refers to one specific cause of the syndrome, an adenoma of the pituitary gland that secretes large amounts of ACTH and, in turn, elevates cortisol levels. This patient has a diagnosis of Cushing’s disease, and this is, therefore, the underlying cause in this case.
The endogenous causes of Cushing’s syndrome include:
Pituitary adenoma (Cushing’s disease)
Ectopic corticotropin syndrome, e.g. small cell carcinoma of the lung
Adrenal hyperplasia
Adrenal adenoma
Adrenal carcinoma -
This question is part of the following fields:
- Endocrine Physiology
- Physiology
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Question 85
Incorrect
-
A 27-year-old man has been diagnosed with testicular cancer and has spread to the regional lymph nodes.
The lymph from the testes will drain to which of the following nodes?Your Answer: Retro-aortic lymph nodes
Correct Answer: Para-aortic lymph nodes
Explanation:Testes are retroperitoneal organs and its lymphatic drainage is to the lumbar and para-aortic nodes along the lumbar vertebrae.
The scrotum is the one which drains into the nearby superficial inguinal nodes.
The glans penis and clitoris drains into the deep inguinal lymph nodes.
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This question is part of the following fields:
- Abdomen And Pelvis
- Anatomy
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Question 86
Incorrect
-
A 44 year old woman sustains an injury to the median nerve at the elbow after falling awkwardly. Which of the following clinical features are you LEAST likely to see on examination:
Your Answer: Hand of Benediction appearance when the patient is asked to make a fist
Correct Answer: Loss of flexion of the medial two digits
Explanation:Flexion of the index and middle fingers at the IPJs is lost due to paralysis of the flexor digitorum superficialis and the lateral half of the flexor digitorum profundus. Flexion of the MCPJs of the index and middle fingers are lost due to paralysis of the lateral two lumbrical muscles. Flexion of the ring and little fingers are preserved as these are supported by the medial half of the flexor digitorum profundus and the medial two lumbrical muscles, 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 87
Incorrect
-
In the emergency room, a 28-year-old woman complains of wobbly and slurred speech, is unable to do the heel-shin test, and has nystagmus. The following signs are most likely related to damage to which of the following areas:
Your Answer: Occipital lobe
Correct Answer: Cerebellum
Explanation:Cerebellar injury causes delayed and disorganized motions. When walking, people with cerebellar abnormalities sway and stagger.
Damage to the cerebellum can cause asynergia, the inability to judge distance and when to stop, dysmetria, the inability to perform rapid alternating movements or adiadochokinesia, movement tremors, staggering, wide-based walking or ataxic gait, a proclivity to fall, weak muscles or hypotonia, slurred speech or ataxic dysarthria, and abnormal eye movements or nystagmus.
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This question is part of the following fields:
- Anatomy
- Central Nervous System
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Question 88
Correct
-
A 25-year-old girl just got back from a trip to Northern India. She complains of headaches and intermittent fever. The fever starts with intense chills, then feels very hot, followed by profuse sweating. She is drowsy and is running a fever of 39.0°C. On examination, there are no palpable lymph nodes or rash seen. She has hepatosplenomegaly.
Which one of the following is the most likely diagnosis?Your Answer: Malaria
Explanation:Malaria is a protozoal infection of red blood cells and the liver. It is caused by the parasite belonging to the genus Plasmodium. It is transmitted by the female mosquito Anopheles.
Several species with distinct features:
P. vivax/P. ovale
P. malariae
P. falciparumThe common symptoms of malaria are:
Paroxysms of fever – a cyclical occurrence of:
1) a cold phase – the patient experiences intense chills
2) a hot stage – the patient feels extremely hot
3) a sweating stage – the fever declines and the patient sweats profusely
– Fever recurs at regular intervals (48hrs, 72hrs): Variable by species of PlasmodiumAnaemia (RBC infection)
– Severity varies by species of Plasmodium
– Haemolytic: sometimes jaundiceSplenomegaly
Also nonspecific symptoms:
– Sweating
– fatigue
– malaise
– arthralgias
– headache
– Sometimes cough, vomiting, diarrhoea -
This question is part of the following fields:
- Microbiology
- Specific Pathogen Groups
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Question 89
Incorrect
-
A 60-year-old female has a past medical history of diverticular disease. She now presents in the clinic with crampy abdominal pain. The nurse at the triage suggests prescribing hyoscine butyl bromide to help relieve the abdominal pain. However, after administering this treatment, the patient develops a side-effect to the medication.
What side-effect of using hyoscine butyl bromide is she MOST likely to develop out of the following?Your Answer: Anaphylaxis
Correct Answer: Dry mouth
Explanation:Hyoscine butylbromide is an antispasmodic drug that blocks muscarinic receptors and reduces intestinal motility. It is used for gastrointestinal and genitourinary smooth muscle spasms and symptomatic relief of IBS.
It has the following side-effects:
1. Constipation
2. Dizziness
3. Drowsiness
4. Dry mouth
5. Dyspepsia
6. Flushing
7. Headache
8. Nausea and vomiting
9. Palpitations
10. Skin reactions
11. Tachycardia
12. Urinary disorders
13. Disorders of vision -
This question is part of the following fields:
- Gastrointestinal Pharmacology
- Pharmacology
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Question 90
Incorrect
-
Despite taking the oral contraceptive pill, a 29-year-old woman becomes pregnant. During a medication review, you discover that she is epileptic and that her antiepileptic therapy has recently been changed.
Which of the following antiepileptics is most likely to impair the oral contraceptive pill's effectiveness?Your Answer: Levetiracetam
Correct Answer: Carbamazepine
Explanation:The metabolism of ethinyl oestradiol and progestogens has been shown to be increased by enzyme-inducing antiepileptics. The oral contraceptive pill (OCP) is less effective in preventing pregnancy as a result of this increased breakdown.
Antiepileptic drugs that induce enzymes include:
Carbamazepine
Phenytoin
Phenobarbital
TopiramateAntiepileptics that do not induce enzymes are unlikely to affect contraception. Non-enzyme-inducing anticonvulsants include the following:
Clonazepam
Gabapentin
Levetiracetam
Piracetam
Sodium valproate is a type of valproate that is used toLamotrigine is an antiepileptic drug that does not cause the production of enzymes. It does, however, require special consideration, unlike other non-enzyme-inducing antiepileptics. The OCP does not appear to affect epilepsy directly, but it does appear to lower lamotrigine levels in the blood. This could result in a loss of seizure control and the occurrence of seizures.
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This question is part of the following fields:
- CNS Pharmacology
- Pharmacology
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Question 91
Incorrect
-
Among the following infectious diseases, which is typically considered to have an incubation period of 3 weeks and longer?
Your Answer: Rubella
Correct Answer: Infectious mononucleosis
Explanation:Infectious mononucleosis is caused by Epstein-Barr virus (EBV). The incubation period for EBV varies from 2 weeks to 2 months.
The usual incubation period for rubella is 14 days; with a range of 12 to 23 days.
Gonorrhoea has a short incubation period of approximately 2 to 7 days.
The mumps virus can be isolated from infected saliva and swabs rubbed over the Stensen’s duct from 9 days before onset of symptoms until 8 days after parotitis appears.
Scarlet fever, which appears within 1 to 2 days after bacterial infection, is characterized by a diffuse red rash that appears on the upper chest and spreads to the trunk and extremities. The rash disappears over the next 5 to
7 days and is followed by desquamation. -
This question is part of the following fields:
- Microbiology
- Specific Pathogen Groups
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Question 92
Correct
-
A patient presents with an adducted eye at rest which cannot abduct past the midline, which of the following cranial nerves is most likely to be affected:
Your Answer: Abducens nerve
Explanation:Abducens nerve palsies result in a convergent squint at rest (eye turned inwards) with inability to abduct the eye because of unopposed action of the rectus medialis. The patient complains of horizontal diplopia when looking towards the affected side. With complete paralysis, the eye cannot abduct past the midline.
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This question is part of the following fields:
- Anatomy
- Cranial Nerve Lesions
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Question 93
Correct
-
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 94
Incorrect
-
An X-ray of a 24-year-old female hockey player who arrives at the hospital with a left foot injury reveals an avulsion fracture of the fifth metatarsal tuberosity. Which of the following muscles is most likely responsible for the movement of the fractured fragment?
Your Answer: Fibularis tertius
Correct Answer: Fibularis brevis
Explanation:An avulsion fracture of the base of the fifth metatarsal happens when the ankle is twisted inwards.
When the ankle is twisted inwards a muscle called the fibularis brevis contracts to stop the movement and protect the ligaments of the ankle.
The base of the fifth metatarsal is where this muscle is attached. The group of lateral leg muscles that function to plantarflex the foot includes the fibularis brevis and the fibularis longus.
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This question is part of the following fields:
- Anatomy
- Lower Limb
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Question 95
Incorrect
-
Approximately how long is the duration of a lidocaine block (when given with adrenaline):
Your Answer: 30 minutes
Correct Answer: 90 minutes
Explanation:Lidocaine is a tertiary amine that is primarily used as a local anaesthetic but can also be used intravenously in the treatment of ventricular dysrhythmias.
Lidocaine works as a local anaesthetic by diffusing in its uncharged base form through neural sheaths and the axonal membrane to the internal surface of the cell membrane sodium channels. Here it alters signal conduction by blocking the fast voltage-gated sodium channels. With sufficient blockage, the membrane of the postsynaptic neuron will not depolarise and will be unable to transmit an action potential, thereby preventing the transmission of pain signals.
Each 1 ml of plain 1% lidocaine solution contains 10 mg of lidocaine hydrochloride. The maximum safe dose of plain lidocaine is 3 mg/kg. When administered with adrenaline 1:200,000, the maximum safe dose is 7 mg/kg. Because of the risk of vasoconstriction and tissue necrosis, lidocaine should not be used in combination with adrenaline in extremities such as fingers, toes, and the nose.
The half-life of lidocaine is 1.5-2 hours. Its onset of action is rapid within a few minutes, and it has a duration of action of 30-60 minutes when used alone. Its duration of action is prolonged by co-administration with adrenaline (about 90 minutes).
Lidocaine tends to cause vasodilatation when used locally. This is believed to be due mainly to the inhibition of action potentials via sodium channel blocking in vasoconstrictor sympathetic nerves. -
This question is part of the following fields:
- Anaesthesia
- Pharmacology
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Question 96
Incorrect
-
A 7-year-old boy is brought to the emergency room with complaints of a red and painful left eye. Upon physical examination, it was noted that there is the presence of conjunctival erythema. A mucopurulent discharge and crusting of the lid was also evident. A diagnosis of bacterial conjunctivitis was made.
According to the latest NICE guidelines, which of the following should NOT be a part of the management of this patient?Your Answer: Inform the mother that infective conjunctivitis is contagious
Correct Answer: Topical antibiotics should be prescribed routinely
Explanation:The following are the NICE guidelines on the management of bacterial conjunctivitis:
– Infective conjunctivitis is a self-limiting illness that usually settles without treatment within 1-2 weeks. If symptoms persist for longer than two weeks they should return for review.
– Seek medical attention urgently if marked eye pain or photophobia, loss of visual acuity, or marked redness of the eye develop.
– Remove contact lenses, if worn, until all symptoms and signs of infection have completely resolved and any treatment has been completed for 24 hours.
– Lubricant eye drops may reduce eye discomfort; these are available over the counter, as well as on prescription.
– Clean away infected secretions from eyelids and lashes with cotton wool soaked in water.
– Wash hands regularly, particularly after touching the eyes.
– Avoid sharing pillows and towels.
– It is not necessary to exclude a child from school or childcare if they have infective conjunctivitis, as mild infectious illnesses should not interrupt school attendance. An exception would be if there is an outbreak of infective conjunctivitis, when advice should be sought from the Health Protection Agency by the school.
– Adults who work in close contact with others, or with vulnerable patients, should avoid such contact until the discharge has settled. -
This question is part of the following fields:
- Microbiology
- Specific Pathogen Groups
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Question 97
Incorrect
-
A 40-year-old man with reduced urine output, nausea, and confusion also has a 150% rise of creatinine from baseline over the past 7 days. A diagnosis of acute kidney injury (AKI) is made after more tests are done.
His AKI stage is?Your Answer: Stage 1
Correct Answer: Stage 2
Explanation:This patient with a 150% rise of creatinine above baseline within 7 days has stage 2 Acute kidney injury (AKI).
AKI stages are as follows:
Stage 1
Creatinine rise of 26 micromole/L or more within 48 hours, or
Creatinine rise of 50-99% from baseline within 7 days (1.5-1.99 x baseline),or
Urine output <0.5 mL/kg/hour for more than 6 hours Stage 2
Creatinine rise of 100-199% from baseline within 7 days (2.0-2.99 x baseline),or
Urine output <0.5 mL/kg/hour for more than 12 hours Stage 3
Creatinine rise of 200% or more from baseline within 7 days (3.0 or more x baseline), or
Creatinine rise to 354 micromole/L or more with acute rise of 26 micromole/L or more within 48 hours or 50% or more rise within 7 days, or
Urine output <0.3 mL/kg/hour for 24 hours or anuria for 12 hours -
This question is part of the following fields:
- General Pathology
- Pathology
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Question 98
Incorrect
-
A suicidal patient had lacerated his wrist, which resulted in an ulnar nerve injury. Which of the following will confirm the presence of an ulnar nerve injury?
Your Answer: Weakness of wrist flexion
Correct Answer: Claw hand appearance
Explanation:An ulnar injury may result in abnormal sensations in the little finger and ring finger, usually on the palm side, weakness, and loss of coordination of the fingers.
A claw like deformity of the hand and wrist is present. Pain, numbness, decreased sensation, tingling, or burning sensation in the areas controlled by the nerve are also possible.
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This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 99
Correct
-
Aside from the inability to extend the leg above the knee, which of the following clinical symptoms should you anticipate seeing in a patient who had a pelvic and right leg injury as well as femoral nerve damage?
Your Answer: Loss of sensation over the anterior thigh
Explanation:The femoral nerve runs down the front of the leg from the pelvis. It gives the front of the thigh and a portion of the lower leg sensation.
Extension of the leg at the knee joint, flexion of the thigh at the hip are produced by muscles that is primarily innervated by the femoral nerve.
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This question is part of the following fields:
- Anatomy
- Lower Limb
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Question 100
Incorrect
-
All of the following cause bronchoconstriction, EXCEPT for:
Your Answer: Beta-blockers
Correct 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 101
Correct
-
Regarding bias, which of the following statements is CORRECT:
Your Answer: Bias leads to the systematic difference between the results from a study and the true states of affair.
Explanation:Bias is the term used to describe an error at any stage of the study that was not due to chance. Bias leads to the systematic difference between the results from a study and the true states of affair. Bias may be introduced at all stages of the research process, from study design, through to analysis and publication. Bias can create a spurious association or mask a real association.Good research design can reduce the effect of bias (e.g. blinding, randomisation) but they cannot eliminate it completely. Increasing the sample size does not reduce bias.
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This question is part of the following fields:
- Evidence Based Medicine
- Study Methodology
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Question 102
Incorrect
-
A 70-year-old man has a resting tremor, rigidity, bradykinesia, and a shuffling gait. Parkinson's disease is caused by one of the following mechanisms:
Your Answer: A vascular lesion of the subthalamic nucleus
Correct Answer: Loss of dopaminergic neurons in the substantia nigra
Explanation:Parkinson’s disease (PD) is one of the most common neurologic disorders, affecting approximately 1% of individuals older than 60 years and causing progressive disability that can be slowed but not halted, by treatment. The 2 major neuropathologic findings in Parkinson’s disease are loss of pigmented dopaminergic neurons of the substantia nigra pars compacta and the presence of Lewy bodies and Lewy neurites. See the images below.
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This question is part of the following fields:
- Anatomy
- Central Nervous System
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Question 103
Incorrect
-
What is the primary function of the mitochondria?
Your Answer: The transcription of ribosomal RNA
Correct Answer: The production of the cell's supply of chemical energy
Explanation:The mitochondria is responsible for the production of the cell’s supply of chemical energy. It does this by using molecular oxygen, sugar and small fatty acid molecules to generate adenosine triphosphate (ATP) by a process ss known as oxidative phosphorylation. An enzyme called ATP synthase is required.
Transcription of ribosomal RNA occurs in the nucleolus
Production of messenger RNA occur in the nucleus
Production of lysosome occurs in the Golgi apparatus
The post-translational processing of newly made proteins occurs in the endoplasmic reticulum
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This question is part of the following fields:
- Basic Cellular Physiology
- Physiology
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Question 104
Incorrect
-
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: Somatostatin
Correct 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 105
Incorrect
-
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 106
Incorrect
-
Regarding the human cell, which of the following cell organelles is responsible for the production of ATP:
Your Answer: Nucleus
Correct Answer: Mitochondria
Explanation:Mitochondria are membrane-bound organelles that are responsible for the production of the cell’s supply of chemical energy. This is achieved by using molecular oxygen to utilise sugar and small fatty acid molecules to generate adenosine triphosphate (ATP). This process is known as oxidative phosphorylation and requires an enzyme called ATP synthase. ATP acts as an energy-carrying molecule and releases the energy in situations when it is required to fuel cellular processes. Mitochondria are also involved in other cellular processes, including Ca2+homeostasis and signalling. Mitochondria contain a small amount of maternal DNA.
Mitochondria have two phospholipid bilayers, an outer membrane and an inner membrane. The inner membrane is intricately folded inwards to form numerous layers called cristae. The cristae contain specialised membrane proteins that enable the mitochondria to synthesise ATP. Between the two membranes lies the intermembrane space, which stores large proteins that are required for cellular respiration. Within the inner membrane is the perimitochondrial space, which contains a jelly-like matrix. This matrix contains a large quantity of ATP synthase.
Mitochondrial disease, or mitochondrial disorder, refers to a group of disorders that affect the mitochondria. When the number or function of mitochondria in the cell are disrupted, less energy is produced and organ dysfunction results. -
This question is part of the following fields:
- Basic Cellular
- Physiology
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Question 107
Incorrect
-
A 58-year-old man showing symptoms of increase in weight, proximal muscular weakening and withering, easy bruising, and acne. You notice that he has a full, plethoric aspect to his face, as well as significant supraclavicular fat pads, when you examine him. His blood pressure is 158/942 mmHg, and his glucose tolerance has lately been impaired. His potassium level is 3.2 mmol/L.
What is the MOST LIKELY diagnosis?Your Answer: Phaeochromocytoma
Correct Answer: Cushing’s syndrome
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.
Cushing’s syndrome has a wide range of clinical manifestations that are dependent on the degree of cortisol overproduction. The appearance might be vague and the diagnosis difficult to detect when cortisol levels are just somewhat elevated. On the other hand, in long-term cases of severely increased cortisol levels, the presentation might be colourful and the diagnosis simple.
Cushing’s syndrome has the following clinical features:
Obesity and weight growth in the true sense
Supraclavicular fat pads are fat pads that are located above the clavicle.
Buffalo hump
Fullness and plethora of the face (‘moon facies’)
Muscle atrophy and weakening at the proximal level
Diabetes mellitus, also known as impaired glucose tolerance
Hypertension
Skin thinning and bruising
Depression
Hirsutism
Acne
Osteoporosis
Amenorrhoea or oligomenorrhoeaCortisol levels fluctuate throughout the day, with the greatest levels occurring around 0900 hours and the lowest occurring at 2400 hrs during sleep. The diurnal swing of cortisol levels is lost in Cushing’s syndrome, and levels are greater during the whole 24-hour period. In the morning, levels may be normal, but they may be high at night-time, when they are generally repressed. As a result, random cortisol testing is not an effective screening technique and is not advised.
The following are the two most common first-line screening tests:
Cortisol levels in the urine are measured every 24 hours.
A diagnosis of Cushing’s syndrome can be made if more than two collections measure cortisol excretion more than three times the upper limit of normal.
Physical stress (e.g., excessive exercise, trauma), mental stress (e.g., sadness), alcohol or drug misuse, complex diabetes, and pregnancy can all cause false positives.
Renal dysfunction, inadequate collection, and cyclical Cushing’s disease can all cause false negatives.
The overnight low-dose dexamethasone suppression test (LDDST) involves giving 1 mg of dexamethasone at 11 p.m. and measuring blood cortisol levels at 8 a.m. the next day.
Cushing’s syndrome is diagnosed when cortisol is not suppressed to less than 50 nmol/L.
It might be difficult to tell the difference between mild Cushing’s disease and normal cortisol production.
False positives can occur as a result of depression, severe systemic sickness, renal failure, prolonged alcohol misuse, old age, and the use of hepatic enzyme-inducing medicines, among other things.
False negatives are extremely uncommon in Cushing’s disease patients.A characteristic biochemical picture might also be helpful in confirming the 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 108
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 109
Incorrect
-
Lidocaine's mechanism of action as a local aesthetic is as follows:
Your Answer: Blocks Ca+ channels
Correct Answer: Blocks influx of Na+ through voltage-gated Na+ channels
Explanation:Local anaesthetics prevent generation/conduction of nerve impulses by reducing sodium permeability and increasing action potential threshold; inhibits depolarization, which results in blockade of conduction
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This question is part of the following fields:
- Anaesthesia
- Pharmacology
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Question 110
Incorrect
-
What is the average healing time for a femoral shaft fracture under normal circumstances? Choose ONE answer.
Your Answer: 10 weeks
Correct Answer: 12 weeks
Explanation:The process of fracture healing occurs naturally after traumatic bone disruption and begins with haemorrhage, then progresses through Inflammatory, reparative, and remodelling stages
Average healing times of common fractures are:
Femoral shaft: 12 weeks
Tibia: 10 weeks
Phalanges: 3 weeks
Metacarpals: 4-6 weeks
Distal radius: 4-6 weeks
Humerus: 6-8 weeks -
This question is part of the following fields:
- General Pathology
- Pathology
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Question 111
Incorrect
-
Regarding myeloma, which of the following statements is CORRECT:
Your Answer: Myeloma is most common in Caucasian populations.
Correct Answer: Myeloma is associated with marked rouleaux formation on blood film.
Explanation:98% of cases of myeloma occur over the age of 40 years with a peak incidence between 65 and 70 years. The disease is twice as common in black individuals compared to those of white or Asian origin. Laboratory findings include presence of a paraprotein in serum/urine (the paraprotein is IgG in 60% of cases, IgA in 20% and light chain only in almost all the rest) and marked Rouleaux formation on blood film. There is no cure for myeloma. The overall median survival is now 7-10 years and in younger (less than 50 years) patients it can be over 10 years.
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This question is part of the following fields:
- Haematology
- Pathology
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Question 112
Incorrect
-
A patient is diagnosed as having a glucagonoma. Her blood serum glucagon concentration is 1246 pg/mL.
Glucagon INHIBITS which of the following processes? Select ONE answer only.Your Answer: The breakdown of glycogen to glucose-6-phosphate
Correct Answer: Glycolysis
Explanation:Glucagon is a peptide hormone that is produced and secreted by alpha cells of the islets of Langerhans, which are located in the endocrine portion of the pancreas. The main physiological role of glucagon is to stimulate hepatic glucose output, thereby leading to increases in glycaemia. It provides the major counter-regulatory mechanism to insulin in maintaining glucose homeostasis.
Hypoglycaemia is the principal stimulus for the secretion of glucagon but may also be used as an antidote in beta-blocker overdose and in anaphylaxis in patients on beta-blockers that fail to respond to adrenaline.
Glucagon then causes:
Glycogenolysis
Gluconeogenesis
Lipolysis in adipose tissue
The secretion of glucagon is also stimulated by:
Adrenaline
Cholecystokinin
Arginine
Alanine
Acetylcholine
The secretion of glucagon is inhibited by:
Insulin
Somatostatin
Increased free fatty acids
Increased urea productionGlycolysis is the metabolic pathway that converts glucose into pyruvate. The free energy released by this process is used to form ATP and NADH. Glycolysis is inhibited by glucagon, and glycolysis and gluconeogenesis are reciprocally regulated so that when one cell pathway is activated, the other is inactive and vice versa.
Glucagon has a minor effect of enhancing lipolysis in adipose tissue. Lipolysis is the breakdown of lipids and involves the hydrolysis of triglycerides into glycerol and free fatty acids. It makes fatty acids available for oxidation.
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This question is part of the following fields:
- Endocrine Physiology
- Physiology
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Question 113
Incorrect
-
A 38-year-old taxi driver sustained blunt force trauma to his anterior chest from the steering wheel of his car after falling asleep while driving headlong into an oncoming HGV lorry. Bruising around his sternum was observed, which appears to be the central point of impact.
Which of the following structures is most likely injured by the blunt force trauma?Your Answer: Base
Correct Answer: Right ventricle
Explanation:In its typical anatomical orientation, the heart has 5 surfaces formed by different internal divisions of the heart:
Anterior (or sternocostal) – Right ventricle
Posterior (or base) – Left atrium
Inferior (or diaphragmatic) – Left and right ventricles
Right pulmonary – Right atrium
Left pulmonary – Left ventricle -
This question is part of the following fields:
- Anatomy
- Thorax
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Question 114
Incorrect
-
Which of the following is NOT a typical clinical feature of beta-thalassaemia major:
Your Answer: Osteoporosis
Correct Answer: Increased bleeding tendency
Explanation:Features include:
– severe anaemia (becoming apparent at 3 – 6 months when the switch from gamma-chain to beta-chain production takes place)
– failure to thrive
– hepatosplenomegaly (due to excessive red cell destruction, extramedullary haemopoiesis and later due to transfusion related iron overload)
– expansion of bones (due to marrow hyperplasia, resulting in bossing of the skull and cortical thinning with tendency to fracture)
– increased susceptibility to infections (due to anaemia, iron overload, transfusion and splenectomy)
– osteoporosis
– hyperbilirubinaemia and gallstones
– hyperuricaemia and gout
– other features of haemolytic anaemia
– liver damage and other features of iron overload -
This question is part of the following fields:
- Haematology
- Pathology
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Question 115
Incorrect
-
Clostridium difficile primarily causes which of the following infectious diseases:
Your Answer: Necrotising fasciitis
Correct Answer: Pseudomembranous colitis
Explanation:Clostridium difficile causes pseudomembranous colitis, an acute inflammatory diarrhoeal disease and an important cause of morbidity and mortality in hospitals. Gas gangrene is primarily caused by Clostridium perfringens. Tetanus is caused by Clostridium tetani. Toxic shock syndrome may be caused by Staphylococcus aureus or Streptococcus pyogenes. Necrotising fasciitis is most commonly caused by Streptococcus pyogenes but has a multitude of causes.
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This question is part of the following fields:
- Microbiology
- Pathogens
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Question 116
Incorrect
-
The 'bucket handle' movement of the thoracic wall describes which of the following movements:
Your Answer: The clavicle moving upwards
Correct Answer: The middles of the shafts of the ribs moving upwards and laterally
Explanation:Because the middles of the shafts of the ribs are lower than either the anterior or posterior end, elevation of the ribs also moves the middles of the shafts laterally. This ‘bucket handle’ upwards and lateral movement increases the lateral dimensions of the thorax.
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This question is part of the following fields:
- Anatomy
- Thorax
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Question 117
Correct
-
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: 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 118
Correct
-
Regarding gastric motility and emptying, which of the following statements is CORRECT:
Your Answer: Gastric emptying is inhibited by the presence of the products of fat digestion in the duodenum.
Explanation:Gastric emptying is decreased by the presence of fats in the duodenum (by stimulating release of cholecystokinin). Mixing of the food with gastric secretions takes place in the distal body and antrum of the stomach where the muscularis externa layer is thicker. The stomach has an additional inner oblique smooth muscle layer (in addition to the inner circular layer and outer longitudinal layer). Gastric emptying is increased by a low gastric pH and decreased by a low duodenal pH.
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This question is part of the following fields:
- Gastrointestinal
- Physiology
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Question 119
Incorrect
-
Which statement accurately describes the osmolality in the various parts of the Henle Loop?
Your Answer: The osmolality of tubular fluid increases as it passes through the descending limb to a maximum of approximately 2000 mOsm
Correct Answer: The osmolality of fluid in the descending loop equals that of the peritubular fluid
Explanation:The Loop of Henle connects the proximal tubule to the distal convoluted tubule and lies parallel to the collecting ducts. It consists of three major segments, including the descending thin limb, the ascending thin limb, and the ascending thick limb. These segments are differentiated based on structure, anatomic location, and function.
The main function of the loop of Henle is to recover water and sodium chloride from urine. When fluid enters the loop of Henle, it has an osmolality of approximately 300 mOsm, and the main solute is sodium.
The thin descending limb has a high water permeability but a low ion permeability. Because it lacks solute transporters, it cannot reabsorb sodium. Aquaporin 1 (AQP1) channels are used to passively absorb water in this area. The peritubular fluid becomes increasingly concentrated as the loop descends into the medulla, causing water to osmose out of the tubule. The tubular fluid in this area now equalizes to the osmolality of the peritubular fluid, to a maximum of approximately 1200 mOsm in a long medullary loop of Henle and 600 mOsm in a short cortical loop of Henle.
The thin ascending limb is highly permeable to ions and impermeable to water. It allows the passive movement of sodium, chloride, and urea down their concentration gradients, so urea enters the tubule and sodium and chloride leave. Reabsorption occurs paracellularly due to the difference in osmolarity between the tubule and the interstitium.
The thick ascending limb is also impermeable to water but actively transports sodium, potassium, and chloride out of the tubular fluid. The osmolality of the tubular fluid is lower compared to the surrounding peritubular fluid. This area is water impermeable. This results in tubular fluid leaving the loop of Henle with an osmolality of approximately 100 mOsm, which is lower than the osmolality of the fluid entering the loop, and urea being the solute.
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This question is part of the following fields:
- Physiology
- Renal Physiology
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Question 120
Incorrect
-
What is the mechanism of action of captopril:
Your Answer: Inhibition of inactivated Na+ channels
Correct Answer: Angiotensin-converting enzyme inhibitor
Explanation:Captopril is an angiotensin-converting enzyme (ACE) inhibitor, which inhibits the conversion of angiotensin I to angiotensin II.
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This question is part of the following fields:
- Cardiovascular
- Pharmacology
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Question 121
Incorrect
-
Regarding the penis, which of the following statements is CORRECT:
Your Answer: The nerves and vessels lies deep to the corpus cavernosum.
Correct Answer: The corpus spongiosum is ventral in the erect penis.
Explanation:Because the anatomical position of the penis is erect, the paired corpora cavernosa are defined as dorsal in the body of the penis and the single corpus spongiosum as ventral. The nerves and vessels lie superficial to the corpus cavernosum. The urethra lies within the corpus spongiosum.
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This question is part of the following fields:
- Abdomen
- Anatomy
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Question 122
Incorrect
-
After collapsing in his nursing home, a 70-year-old man is brought into the ER. He is a known case of diabetes mellitus and is on medication for it. An RBS of 2.5 mmol/L (3.9-5.5 mmol/L) is recorded in the ER.
Out of the following, which medication for diabetes mellitus is MOST likely responsible for his hypoglycaemic episode?Your Answer: Acarbose
Correct Answer: Pioglitazone
Explanation:Pioglitazone is used to treat type 2 diabetes mellitus. It selectively stimulates the nuclear receptor peroxisome proliferator-activated receptor gamma (PPAR-γ) and to a lesser extent PPAR-α.
Of the medications mentioned in this question, only pioglitazone is a recognized cause of hypoglycaemia.
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This question is part of the following fields:
- Endocrine Pharmacology
- Pharmacology
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Question 123
Correct
-
You've been summoned to the resuscitation area to assist a patient who is having a seizure. As part of the treatment protocol, a benzodiazepine dose is given.
Which of the following statements about the use of benzodiazepines in seizures is correct?Your Answer: Lorazepam can be given by the rectal route
Explanation:A single dose of IV benzodiazepine will terminate the seizure in 60 to 80 percent of patients who present with seizures.
Because benzodiazepines are lipid-soluble, they cross the blood-brain barrier quickly. This explains their quick onset of action.
As a first-line treatment, IV lorazepam should be given. If IV lorazepam is not available, IV diazepam can be used instead, and buccal midazolam can be used if intravenous access cannot be established quickly. Lorazepam can be administered via the rectal route, but it is less reliable and has a lower absorption rate and bioavailability.
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This question is part of the following fields:
- CNS Pharmacology
- Pharmacology
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Question 124
Incorrect
-
Regarding Legionella species which of the following statements is CORRECT:
Your Answer: Legionella jeonii is the main human pathogen.
Correct Answer: They are Gram-negative organisms.
Explanation:Legionella pneumophilais a Gram negative bacterium that is found in natural water supplies and in the soil, transmitted predominantly via inhalation of aerosols generated from contaminated water (direct person-to-person spread of infected patients does not occur). It is the cause of Legionnaires’ disease. Outbreaks of Legionnaires’ disease have been linked to poorly maintained air conditioning systems, whirlpool spas and hot tubs.
The clinical features of the pneumonic form of Legionnaires’ disease include:
Mild flu-like prodrome for 1-3 days
Cough (usually non-productive and occurs in approximately 90%)
Pleuritic chest pain
Haemoptysis
Headache
Nausea, vomiting and diarrhoea
Anorexia
Legionella pneumophilainfections can be successfully treated with macrolide antibiotics, such as erythromycin, or quinolones, such as ciprofloxacin. Tetracyclines, such as doxycycline, can also be used.
The syndrome of inappropriate antidiuretic hormone secretion (SIADH) can occur with Legionnaires’ disease and will result in hyponatraemia as is seen in this case.
Legionella pneumophilainfections are resistant to amoxicillin but can be successfully treated with macrolide antibiotics, such as erythromycin, or quinolones, such as ciprofloxacin. Tetracyclines, such as doxycycline, can also be used. The majority of cases of Legionnaires’ disease are caused by Legionella pneumophila, however many other species of Legionella have been identified.
Legionella longbeachae is another less commonly encountered species that has also been implicated in outbreaks. It is predominantly found in soil and potting compost, and has caused outbreaks of Pontiac fever, the non-respiratory and less severe variant of Legionnaires’ disease. -
This question is part of the following fields:
- Microbiology
- Pathogens
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Question 125
Incorrect
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A 4-year-old child has been convulsing for 20 minutes. She has received two doses of lorazepam. She takes phenytoin for maintenance therapy, and you draw up a phenobarbitone infusion.
What dose of phenobarbitone is advised in the treatment of the convulsing child that reaches that stage of the APLS algorithm? Select ONE answer only.Your Answer: 100 mg/kg over 30-60 minutes
Correct Answer: 20 mg/kg over 30-60 minutes
Explanation:If a convulsing child reaches step 3 of the APLS algorithm, then a phenytoin infusion should be set up at 20 mg/kg over 20 minutes. If they are already taken phenytoin as maintenance therapy, then a phenobarbitone infusion should be set up at 20 mg/kg over 30-60 minutes.
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This question is part of the following fields:
- CNS Pharmacology
- Pharmacology
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Question 126
Incorrect
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A 50-year-old woman with painful joints had some blood tests done with her GP. The test showed she had anti-double stranded DNA antibodies.
Which one of these disorders is most likely to be associated with anti-double stranded DNA antibodies?Your Answer: Polymyositis
Correct Answer: Systemic lupus erythematosus (SLE)
Explanation:CREST syndrome is usually associated with anti-centromere antibodies.
Primary biliary cirrhosis is associated with anti-mitochondrial antibodies.
Sjogren’s syndrome is associated with anti-Ro and anti-La antibodies.
Polymyositis is associated with anti-Jo1 antibodies.
Anti-double stranded DNA antibodies are highly characteristic of systemic lupus erythematosus (SLE). They are a group of anti-nuclear antibodies (ANA) that target double stranded DNA and are implicated in the pathogenesis of lupus nephritis.
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This question is part of the following fields:
- General Pathology
- Pathology
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Question 127
Incorrect
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The renal team is currently prescribing erythropoietin to a patient with chronic kidney disease.
Which of the following statements about erythropoietin is correct?Your Answer: It increases oxygen affinity
Correct Answer: It protects red blood cell progenitors from apoptosis
Explanation:Erythropoietin is a glycoprotein hormone that regulates the formation of red blood cells (red cell production). It is mostly produced by interstitial fibroblasts in the kidney, which are located near the PCT. It is also produced in the liver’s perisinusoidal cells, however this is more common during the foetal and perinatal periods.
The kidneys produce and secrete erythropoietin in response to hypoxia. On red blood cells, erythropoietin has two main effects:
– It encourages stem cells in the bone marrow to produce more red blood cells.
– It protects red blood cell progenitors and precursors from apoptosis by targeting them in the bone marrow.
As a result of the increased red cell mass, the oxygen-carrying capacity and oxygen delivery increase. -
This question is part of the following fields:
- Physiology
- Renal Physiology
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Question 128
Incorrect
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Which of the following is NOT a function of the commensal intestinal bacterial flora:
Your Answer: Involved in the synthesis of vitamin B and vitamin K
Correct Answer: Breakdown of haem into bilirubin
Explanation:Commensal intestinal bacterial flora have a role in:Keeping pathogenic bacteria at bay by competing for space and nutrientConverting conjugated bilirubin to urobilinogen (some of which is reabsorbed and excreted in urine) and stercobilinogen which is excreted in the faecesThe synthesis of vitamins K, B12, thiamine and riboflavinThe breakdown of primary bile acids to secondary bile acidsThe breakdown of cholesterol, some food additives and drugs
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This question is part of the following fields:
- Gastrointestinal
- Physiology
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Question 129
Incorrect
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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: 1-2 hours
Correct 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 130
Incorrect
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Which of the following is a primary action of calcitonin:
Your Answer: Inhibition of 1-alpha-hydroxylase activity in the kidneys
Correct Answer: Decreased bone resorption through inhibition of osteoclast activity
Explanation:Calcitonin is a 32 amino acid polypeptide that is primarily synthesised and released by the parafollicular cells (C-cells) of the thyroid gland in response to rising or high levels of plasma Ca2+ions. Its primary role is to reduce the plasma calcium concentration, therefore opposing the effects of parathyroid hormone.
Secretion of calcitonin is stimulated by:
– Increased plasma calcium concentration
– Gastrin
– Pentagastrin
– The main actions of calcitonin are:
– Inhibition of osteoclastic activity (decreasing calcium and phosphate resorption from bone)
– Stimulation of osteoblastic activity
– Decreases renal calcium reabsorption
– Decreases renal phosphate reabsorption -
This question is part of the following fields:
- Endocrine
- Physiology
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Question 131
Correct
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Salivary glands produce saliva which is mostly water, but it also contains a range of essential chemicals such as mucus, electrolytes, antibiotic agents, and enzymes.
Which of the following is a carbohydrate-digesting enzyme found in saliva?
Your Answer: Amylase
Explanation:The acinar cells of the parotid and submandibular glands release amylase. Amylase begins starch digestion before food is even eaten, and it works best at a pH of 7.4.
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This question is part of the following fields:
- Gastrointestinal Physiology
- Physiology
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Question 132
Incorrect
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A 32-year-old woman with a history of bipolar disorder exhibits lithium toxicity symptoms.
Which of the following is the MOST LIKELY feature to be present?Your Answer: Reduced muscle tone
Correct Answer: Clonus
Explanation:Lithium toxicity manifests itself in the following ways:
Ataxia
Clonus
Coma
Confusion
Convulsions
Diarrhoea
Increased muscle tone
Nausea and vomiting
Nephrogenic diabetes insipidus
Renal failure
Tremor -
This question is part of the following fields:
- CNS Pharmacology
- Pharmacology
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Question 133
Incorrect
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A 45-year-old man, a known case of epilepsy, visits his neurologist with complaints of red, swollen gums.
Which of the following medications is most likely responsible for his symptoms?Your Answer: Topiramate
Correct Answer: Phenytoin
Explanation:Phenytoin is a commonly used antiepileptic drug. A well-recognized side-effect of phenytoin is gingival enlargement and occurs in about 50% of patients receiving phenytoin. It is believed that reduced folate levels may cause this, and evidence suggests that folic acid supplementation may help prevent this in patients starting phenytoin.
As evidence suggests, drug-induced gingival enlargement may also improve by substituting with other anticonvulsant drugs and reinforcing a good oral hygiene regimen. Surgical excision of hyperplastic gingiva is often necessary to correct the aesthetic and functional impairment associated with this condition to manage it successfully.
Phenytoin is also the only anticonvulsant therapy associated with the development of Dupuytren’s contracture.
Other side effects are:
1. Ataxia
2. Drug-induced lupus
3. Hirsutism
4. Pruritic rash
5. Megaloblastic anaemia
6. Nystagmus -
This question is part of the following fields:
- CNS Pharmacology
- Pharmacology
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Question 134
Incorrect
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A 2nd-year medical student is solving an exam paper with questions about the immune system. She comes across a question regarding innate immunity. Innate immunity is the immunity naturally present within the body from birth.
Which ONE of the following is not a part of this type of immunity?Your Answer: The complement system
Correct Answer: Antibody production
Explanation:Innate immunity, also called non-specific immunity, refers to the components of the immune system naturally present in the body at birth.
The components of innate immunity include:
1) Natural Killer Cells
2) Neutrophils
3) Macrophages
4) Mast Cells
5) Dendritic Cells
6) Basophils.Acquired or adaptive immunity is acquired in response to infection or vaccination. Although the response takes longer to develop, it is also a more long-lasting form of immunity.
The components of this system include:
1) T lymphocytes
2) B lymphocytes
3) Antibodies -
This question is part of the following fields:
- General Pathology
- Pathology
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Question 135
Incorrect
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Which of the following is NOT one of insulin's actions:
Your Answer: Increased cellular potassium uptake
Correct Answer: Increased gluconeogenesis
Explanation:Insulin has a number of effects on glucose metabolism, including:
Inhibition of glycogenolysis and gluconeogenesis
Increased glucose transport into fat and muscle
Increased glycolysis in fat and muscle
Stimulation of glycogen synthesis
By inhibiting gluconeogenesis, insulin maintains the availability of amino acids as substrates for protein synthesis. Thus, insulin supports protein synthesis through direct and indirect mechanisms. -
This question is part of the following fields:
- Endocrine
- Pharmacology
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Question 136
Incorrect
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Atracurium is used as a muscle relaxant during endotracheal intubation. This drug’s mechanism of action is best described by which of the following?
Your Answer: Muscarinic acetylcholine receptor antagonist
Correct Answer: Nicotinic acetylcholine receptor antagonist
Explanation:Atracurium is a non-depolarizing neuromuscular blocker that is used to help with intubation and controlled ventilation by causing muscle relaxation and paralysis.
At the neuromuscular junction’s post-synaptic membrane, atracurium competes with acetylcholine for nicotinic (N2) receptor binding sites. This prevents the receptors from being stimulated by acetylcholine.
Muscle paralysis occurs gradually due to the competitive blockade.
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This question is part of the following fields:
- Anaesthesia
- Pharmacology
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Question 137
Incorrect
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Regarding airway resistance, which of the following statements is CORRECT:
Your Answer: Muscarinic antagonists cause bronchoconstriction.
Correct Answer: Airway resistance is predominantly determined by the radius of the airway as described by Poiseuille's law.
Explanation:Flow through airways is described by Darcy’s law which states that flow is directly proportional to the mouth-alveolar pressure gradient and inversely proportional to airway resistance. Airway resistance is primarily determined by the airway radius according to Poiseuille’s law, and whether the flow is laminar or turbulent. Parasympathetic stimulation causes bronchoconstriction and sympathetic stimulation causes bronchodilation, but mediated by beta2-adrenoceptors. Muscarinic antagonists e.g. ipratropium bromide cause bronchodilation.
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This question is part of the following fields:
- Physiology
- Respiratory
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Question 138
Incorrect
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Adenosine has a half-life of approximately:
Your Answer: 30 minutes
Correct Answer: 8 - 10 seconds
Explanation:Adenosine stimulates A1-adenosine receptors and opens acetylcholine sensitive K+ channels, increasing K+ efflux. This hyperpolarises the cell membrane in the atrioventricular node and, by inhibiting the calcium channels, slows conduction in the AVN. As it has a very short duration of action (half-life only about 8 – 10 seconds), most side effects are short lived.
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This question is part of the following fields:
- Cardiovascular
- Pharmacology
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Question 139
Incorrect
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Bile acids are essential for the digestion and absorption of which of the following:
Your Answer: Iron
Correct Answer: Lipids and fat-soluble vitamins
Explanation:Bile acids are synthesised from cholesterol by hepatocyte and excreted into bile. Bile acids are essential for lipid digestion and absorption. Of the bile acids excreted into the intestine, about 95% are reabsorbed into the portal circulation by active transport mechanisms in the distal ileum and recycled by the liver. Many of the bile salts are reabsorbed unaltered, some are converted by intestinal bacteria into secondary bile acids (deoxycholic acid and lithocholic acid) and then reabsorbed and a small proportion escapes reabsorption and is excreted in the faeces.
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This question is part of the following fields:
- Gastrointestinal
- Physiology
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Question 140
Incorrect
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A dermatological examination on a patient presenting with a lump shows a small visible skin elevation containing an accumulation of pus.
Which one of these best describes the lump you have found on examination?Your Answer: Vesicle
Correct Answer: Pustule
Explanation:A pustule is a small visible skin elevation containing an accumulation of pus.
A carbuncle is a collection of individual boils clustered together.
A bulla is a visible collection of clear fluid measuring greater than 0.5 cm in diameter.
A furuncle, or boil, is a pyogenic infection of the hair follicle commonly caused by infection with Staphylococcus aureus.
A vesicle is a visible collection of fluid measuring less than 0.5 cm in diameter.
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This question is part of the following fields:
- General Pathology
- Pathology
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Question 141
Incorrect
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A 26 year old horse rider has a bad fall and sustains a neck injury which displays the following signs:
- ability to extend the wrist against gravity
- paralysis of the hands, trunk, and legs
- absent sensation in the fingers and medial upper arms
- normal sensation over the thumbs
- absent sensation in chest, abdomen, and legs
What is the neurological level of the injury?Your Answer: C5
Correct Answer: C6
Explanation:C1 – C4 INJURY
Most severe of the spinal cord injury levels; paralysis in arms, hands, trunk and legs; patient may not be able to breathe on his or her own, cough, or control bowel or bladder movements; ability to speak is sometimes impaired or reducedC5 INJURY
Person can raise his or her arms and bend elbows; likely to have some or total paralysis of wrists, hands, trunk and legs; can speak and use diaphragm, but breathing will be weakenedC6 INJURY
Nerves affect wrist extension; paralysis in hands, trunk and legs, typically; should be able to bend wrists back; can speak and use diaphragm, but breathing will be weakenedC7 INJURY
Nerves control elbow extension and some finger extension; most can straighten their arm and have normal movement of their shouldersC8 INJURY
Nerves control some hand movement; should be able to grasp and release objectsC5 – Elbow flexors (biceps, brachialis)
C6 – Wrist extensors (extensor carpi radialis longus and brevis)
C7 – Elbow extensors (triceps)
C8 – Finger flexors (flexor digitorum profundus) to the middle fingerC5 – Elbow flexed at 90 degrees, arm at the patient’s side and forearm supinated
C6 – Wrist in full extension
C7 – Shoulder is neutral rotation, adducted and in 90 degrees of flexion with elbow in 45 degrees of flexion
C8 –Full flexed position of the distal phalanx with the proximal finger joints stabilized in a extended position -
This question is part of the following fields:
- Anatomy
- Central Nervous System
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Question 142
Incorrect
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On her most recent blood tests, a 55 year-old female with a history of hypertension was discovered to be hypokalaemic. She is diagnosed with primary hyperaldosteronism.
Which of the following is a direct action of aldosterone?
Your Answer: Secretion of Na + into the distal convoluted tubule
Correct Answer: Secretion of H + into the distal convoluted tubule
Explanation:Aldosterone is a steroid hormone produced in the adrenal cortex’s zona glomerulosa. It is the most important mineralocorticoid hormone in the control of blood pressure. It does so primarily by promoting the synthesis of Na+/K+ATPases and the insertion of more Na+/K+ATPases into the basolateral membrane of the nephron’s distal tubules and collecting ducts, as well as stimulating apical sodium and potassium channel activity, resulting in increased sodium reabsorption and potassium secretion. This results in sodium conservation, potassium secretion, water retention, and a rise in blood volume and blood pressure.
Aldosterone is produced in response to the following stimuli:
Angiotensin II levels have risen.
Potassium levels have increased.
ACTH levels have risen.
Aldosterone’s principal actions are as follows:
Na+ reabsorption from the convoluted tubule’s distal end
Water resorption from the distal convoluted tubule (followed by Na+)
Cl is reabsorbed from the distal convoluted tubule.
K+ secretion into the convoluted distal tubule’s
H+ secretion into the convoluted distal tubule’s -
This question is part of the following fields:
- Physiology
- Renal Physiology
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Question 143
Incorrect
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A patient presents with a laceration on his hand and wrist that has cut the nerve that innervates opponens pollicis.
The opponens pollicis muscle is innervated by which of the following nerves? Select ONE answer only.Your Answer: The deep branch of the ulnar nerve
Correct Answer: The recurrent branch of the median nerve
Explanation:Opponens pollicis is a small, triangular muscle that forms part of the thenar eminence. It originates from the flexor retinaculum and the tubercle of trapezium bone and inserts into the whole length of the first metacarpal bone on its radial side.
Opponens pollicis is innervated by the recurrent branch of the median nerve and receives its blood supply from the superficial palmar arch.
The main action of opponens pollicis is to flex the first metacarpal bone at the carpometacarpal joint, which opposes the thumb towards the centre of the palm. It also medially rotates the first metacarpal bone at the carpometacarpal joint. -
This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 144
Incorrect
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A 25-year-old guy who has had a knee-high plaster cast on his left leg for the past 5 weeks arrives at the emergency department complaining of numbness on the dorsum of his left foot and an inability to dorsiflex or evert his foot. You know that his symptoms are due to fibular nerve compression. Where is the fibular nerve located?
Your Answer: Popliteal fossa
Correct Answer: Neck of fibula
Explanation:Dorsiflexion and eversion of the foot are innervated by the deep fibular nerve and the superficial fibular nerve, respectively.
The common fibular nerve runs obliquely downward along the lateral border of the popliteal fossa (medial to the biceps femoris) before branching at the neck of the fibula.
Thus, it is prone to being affected during an impact injury or fracture to the bone or leg. Casts that are placed too high can also compress the fibular nerve.
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This question is part of the following fields:
- Anatomy
- Lower Limb
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Question 145
Incorrect
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Which of the following represents ventricular repolarisation on the ECG:
Your Answer: ST segment
Correct Answer: T wave
Explanation:P wave = Atrial depolarisation
QRS complex = Ventricular depolarisation
T wave = Ventricular repolarisation -
This question is part of the following fields:
- Cardiovascular
- Physiology
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Question 146
Correct
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Regarding fibrinolytics, which of the following statements is INCORRECT:
Your 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 147
Incorrect
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In a VF arrest, a 6-year-old child is brought to your Emergency Department resuscitation area. He weighs 16 kilogrammes. He's had three DC shocks, but he's still in VF and doesn't have an output.
What amiodarone dose should he get now, according to the most recent APLS guidelines?Your Answer: 16 mg
Correct Answer: 80 mg
Explanation:In a shockable (Vf/pVT) paediatric cardiac arrest, amiodarone should be administered after the third and fifth shocks. The dose is 5 mg/kg (maximum 300 mg) and should be administered over a three-minute period. If at all possible, administration via a central line is recommended.
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This question is part of the following fields:
- Cardiovascular Pharmacology
- Pharmacology
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Question 148
Incorrect
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A 77 year old lady presents to ED with her left leg shortened and externally rotated following slipping and falling on a wet bathroom floor. There is an intracapsular fracture of the neck of femur seen on imaging studies. She is at risk of avascular necrosis of the head of femur.
This is caused by lack of blood supply from which of these arteries?
Your Answer: Obturator artery
Correct Answer: Medial circumflex artery
Explanation:The primary blood supply to the head of the femur is from branches of the medial femoral circumflex artery.
The superior and inferior gluteal arteries supply the hip joint but not the head of femur.
The lateral circumflex artery anastomoses with the medial femoral circumflex artery and assists in supplying the head of femur.
The obturator artery is an important source of blood supply in children up to about 8 years. It gives rise to the artery of the head of femur which runs in the ligamentum teres and is insufficient to supply the head of femur in adults.
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This question is part of the following fields:
- Anatomy
- Lower Limb
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Question 149
Incorrect
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Question 150
Incorrect
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Glucagon may be used as an antidote for overdose with which of the following:
Your Answer:
Correct Answer: Beta blockers
Explanation:Glucagon is a peptide hormone that is produced and secreted by alpha cells of the islets of Langerhans, which are located in the endocrine portion of the pancreas. The main physiological role of glucagon is to stimulate hepatic glucose output, thereby leading to increases in glycaemia. It provides the major counter-regulatory mechanism to insulin in maintaining glucose homeostasis.
Hypoglycaemia is the principal stimulus for the secretion of glucagon but may also be used as an antidote in beta-blocker overdose and in anaphylaxis in patients on beta-blockers that fail to respond to adrenaline.
Glucagon then causes:
Glycogenolysis
Gluconeogenesis
Lipolysis in adipose tissue
The secretion of glucagon is also stimulated by:
Adrenaline
Cholecystokinin
Arginine
Alanine
Acetylcholine
The secretion of glucagon is inhibited by:
Insulin
Somatostatin
Increased free fatty acids
Increased urea productionGlycolysis is the metabolic pathway that converts glucose into pyruvate. The free energy released by this process is used to form ATP and NADH. Glycolysis is inhibited by glucagon, and glycolysis and gluconeogenesis are reciprocally regulated so that when one cell pathway is activated, the other is inactive and vice versa.
Glucagon has a minor effect of enhancing lipolysis in adipose tissue. Lipolysis is the breakdown of lipids and involves the hydrolysis of triglycerides into glycerol and free fatty acids. It makes fatty acids available for oxidation.
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This question is part of the following fields:
- Endocrine
- Pharmacology
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SESSION STATS - PERFORMANCE PER SPECIALTY
