-
Question 1
Incorrect
-
Regarding ampicillin, which of the following statements is CORRECT:
Your Answer: Ampicillin is first line treatment for acute sore throat.
Correct Answer: Ampicillin may cause a widespread maculopapular rash in a patient with glandular fever.
Explanation:Ampicillin is a broad-spectrum antibiotic, active against certain Gram-positive and Gram-negative organisms but is inactivated by penicillinases (similar to amoxicillin in spectrum). Ampicillin is associated with high levels of resistance, therefore it is often not appropriate for blind treatment of infection. It is principally indicated for the treatment of exacerbations of chronic bronchitis and middle ear infections, both of which may be due to Streptococcus pneumoniae and H. influenzae, and for urinary tract infections.
Maculopapular rashes commonly occur with ampicillin (and amoxicillin) but are not usually related to true penicillin allergy. They almost always occur in patients with glandular fever; thus broad-spectrum penicillins should not be used for blind treatment of a sore throat. The risk of rash is also increased in patients with acute or chronic lymphocytic leukaemia or in cytomegalovirus infection.
-
This question is part of the following fields:
- Infections
- Pharmacology
-
-
Question 2
Incorrect
-
After what time period should intravenous phenytoin be used as second-line treatment of status epilepticus?
Your Answer: 30 minutes
Correct Answer: 25 minutes
Explanation:If seizures recur or fail to respond after initial treatment with benzodiazepines within 25 minutes of onset, phenytoin sodium, fosphenytoin sodium, or phenobarbital sodium should be used.
-
This question is part of the following fields:
- Central Nervous System
- Pharmacology
-
-
Question 3
Correct
-
Bile acids are essential for the digestion and absorption of which of the following:
Your 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.
-
This question is part of the following fields:
- Gastrointestinal
- Physiology
-
-
Question 4
Incorrect
-
A 52-year-old man presents to the emergency room with chest pain. He was recently released from the hospital after receiving abciximab during coronary angioplasty.
Which of the following is NOT a contraindication to abciximab (ReoPro) treatment?Your Answer: Stroke within the last 2 years
Correct Answer: Major surgery within the last 6 months
Explanation:Abciximab (ReoPro) is a glycoprotein IIb/IIIa receptor antagonist that is a chimeric monoclonal antibody. It is primarily used during and after coronary artery procedures such as angioplasty to inhibit platelet aggregation.
The use of abciximab is contraindicated in the following situations:
Internal bleeding is present.
Within the last two months, you’ve had major surgery, intracranial surgery, or trauma.
Stroke in the previous two years
Intracranial tumour
Aneurysm or arteriovenous malformation
Haemorrhagic diathesis is a type of haemorrhagic diathesis.
Vasculitis
Retinopathy caused by hypertension -
This question is part of the following fields:
- Cardiovascular Pharmacology
- Pharmacology
-
-
Question 5
Incorrect
-
Innate, or non-specific, immunity is the immune system we are born with.
Which of the following is NOT an example of innate immunity? Select ONE answer only.Your Answer: Natural killer cells
Correct Answer: T-lymphocytes
Explanation:Innate, or non-specific, immunity is the immune system we are born with.
There are three aspects of innate immunity:
1. Anatomical barriers, such as:
The cough reflex
Enzymes in tears and skin oils
Mucus – which traps bacteria and small particles
Skin
Stomach acid
2. Humoral barriers, such as:
The complement system
Interleukin-1
3. Cellular barriers, such as:
Neutrophils
Macrophages
Dendritic cells
Natural killer cells
Antibody production is part of the specific, or inducible immune response. T-lymphocytesare responsible for the cell mediated immune response which is part of specific, or inducible immunity. -
This question is part of the following fields:
- General Pathology
- Pathology
-
-
Question 6
Correct
-
The following structures all lie anteriorly to the oesophagus EXCEPT for the:
Your Answer: Thoracic duct
Explanation:Posterior to the oesophagus, the thoracic duct is on the right side inferiorly but crosses to the left more superiorly (at T5).
-
This question is part of the following fields:
- Anatomy
- Thorax
-
-
Question 7
Correct
-
You examine a 50-year-old female who has a swollen, painful right big toe. She has a history of gout, and this discomfort is identical to prior relapses, according to her. She is currently taking 200 mg of allopurinol per day and has been for the last year. This is her second round of acute gout within this time period. She has no prior medical history to speak of and does not take any other medications. She doesn't have any known drug allergies.
Which of the following management options is the SINGLE MOST APPROPRIATE?Your Answer: Continue with the allopurinol and commence naproxen
Explanation:Allopurinol should not be started during an acute gout episode because it can both prolong and trigger another acute attack. Allopurinol should be continued in patients who are currently taking it, and acute attacks should be treated as usual with NSAIDs or colchicine, as needed.
Non-steroidal anti-inflammatory medications (NSAIDs), such as naproxen, are the first-line treatment for acute gout attacks. Colchicine can be used in situations where NSAIDs are contraindicated, such as in patients with hypertension or those who have had a history of peptic ulcer disease. Because there is no reason for this patient to avoid NSAIDs, naproxen would be the medicine of choice from the list above.
It would be reasonable to titrate up the allopurinol dose once the acute episode has subsided, targeting <6 mg/dl (<360 µmol/l) plasma urate levels .
Febuxostat (Uloric) is a drug that can be used instead of allopurinol to treat persistent gout. -
This question is part of the following fields:
- Musculoskeletal Pharmacology
- Pharmacology
-
-
Question 8
Incorrect
-
Which of the following is NOT typically associated with eosinophilia:
Your Answer: Psoriasis
Correct Answer: Whooping cough
Explanation:An eosinophil leucocytosis is defined as an increase in blood eosinophils above 0.4 x 109/L.It is most frequently due to:
Allergic diseases (e.g. bronchial asthma, hay fever, atopic dermatitis, urticaria)
Parasites (e.g. hookworm, ascariasis, tapeworm, schistosomiasis)
Skin diseases (e.g. psoriasis, pemphigus, urticaria, angioedema)
Drug sensitivity -
This question is part of the following fields:
- Immune Responses
- Pathology
-
-
Question 9
Incorrect
-
A 5 day old, full term neonate is with a unilateral purulent eye discharge noticed earlier that day is brought in. On gram stain of the exudate, no bacteria are seen.
What is the most likely causative pathogen?
Your Answer: Escherichia coli
Correct Answer: Chlamydia trachomatis
Explanation:Conjunctivitis occurring in the first 28 days of life (Ophthalmia neonatorum) is most commonly caused by Chlamydia trachomatis in the UK.
-
This question is part of the following fields:
- Microbiology
- Pathogens
-
-
Question 10
Correct
-
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 FALSE?
Your Answer: Premature infants should have the their immunisation schedule adjusted for gestational age
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. neomycinLive attenuated vaccines are contraindicated in pregnancy except in cases where risk of infection is more than the risks of vaccination.
During times of acute febrile illness, vaccination should be avoided.
12 weeks should elapse after a dose of human immunoglobulin before a live vaccine is administered.
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.
-
This question is part of the following fields:
- Microbiology
- Principles Of Microbiology
-
-
Question 11
Incorrect
-
Regarding aspirin at analgesic doses, which of the following statements is CORRECT:
Your Answer: The increased production of prostaglandins can irritate gastric mucosa.
Correct Answer: It is contraindicated in patients with severe heart failure.
Explanation:Aspirin (at analgesic doses) is contraindicated in severe heart failure. Aspirin irreversibly inhibits cyclooxygenase (COX) enzymes resulting in decreased production of prostaglandins (which can lead to irritation of the gastric mucosa). The analgesic dose is greater than the antiplatelet dose, and taken orally it has a duration of action of about 4 hours. Clinical features of salicylate toxicity in overdose include hyperventilation, tinnitus, deafness, vasodilatation, and sweating.
-
This question is part of the following fields:
- Central Nervous System
- Pharmacology
-
-
Question 12
Correct
-
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
-
-
Question 13
Correct
-
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: 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).
-
This question is part of the following fields:
- Microbiology
- Specific Pathogen Groups
-
-
Question 14
Incorrect
-
Since the fluid that enters the loop of Henle is isotonic, what is its estimated osmolality?
Your Answer: 100 mOsm
Correct Answer: 300 mOsm
Explanation:The loop of Henle connects the proximal tubule to the distal convoluted tubule and lies parallel to the collecting ducts. It is consists of three major segments, the thin descending limb, the thin ascending limb, and the thick ascending limb.
The segments are differentiated based on structure, anatomic location, and function. The main action of the loop of Henle is to recover water and sodium chloride from urine. The liquid entering the loop of Henle is a solution of salt, urea, and other substances traversed along by the proximal convoluted tubule, from which most of the dissolved components are needed by the body, particularly glucose, amino acids, and sodium bicarbonate that have been reabsorbed into the blood.
This fluid is isotonic. Isotonic fluids generally have an osmolality ranging from 270 to 310 mOsm/L. With the fluid that enters the loop of Henle, it is estimated to be 300 mOsm/L. However, after passing the loop, fluid entering the distal tubule is hypotonic to plasma since it has been diluted during its passage.
-
This question is part of the following fields:
- Physiology
- Renal Physiology
-
-
Question 15
Correct
-
A patient with diplopia is found to have eye deviation downwards and outwards. The likely nerves that are affected are:
Your Answer: Oculomotor nerve
Explanation:The results of an oculomotor (CN III) nerve palsy are a depressed and abducted (down and out) eye, ptosis, diplopia, and a fixed and dilated pupil.
-
This question is part of the following fields:
- Anatomy
- Cranial Nerve Lesions
-
-
Question 16
Correct
-
Which of the following cell types in the stomach secretes histamine?
Your Answer: Enterochromaffin-like cells
Explanation:The parietal cells operate in close association with another type of cell called enterochromaffin-like cells (ECL cells), the primary function of which is to secrete histamine. The ECL cells lie in the deep recesses of the oxyntic glands and therefore release histamine indirect contact with the parietal cells of the glands.
-
This question is part of the following fields:
- Gastrointestinal
- Physiology
-
-
Question 17
Correct
-
Which of the following is NOT typically present in the nasopharyngeal flora:
Your Answer: Bacteroides spp.
Explanation:Bacteroides spp. are typically found in the normal flora of the lower gastrointestinal tract. Species commonly found in the flora of the nasopharynx include: Staphylococcus aureus, Staphylococcus epidermidis, Streptococcus pneumoniae, Neisseria meningitidis, Haemophilus influenzae, Corynebacterium spp., Moraxella spp. and Candida spp.
-
This question is part of the following fields:
- Microbiology
- Principles
-
-
Question 18
Correct
-
A 23-year-old male is referred to your haematology clinic after an acute attack of haemolytic anaemia. He was diagnosed with glucose-6-phosphate dehydrogenase deficiency ten years ago.
Which ONE of the following options is FALSE with regards to this disorder?Your Answer: Acute haemolysis can be triggered by cephalosporin antibiotics
Explanation:Glucose-6-phosphate dehydrogenase deficiency is an X-linked recessive disorder in which there is a deficiency of the enzyme G6PD. This causes instability of red blood cell membranes under oxidative stress leading to haemolysis.
Triggers include:
1) Fava beans
2) Sulphonamides
3) Primaquine
4) Anti-TB drugs
5) InfectionsMost individuals will be asymptomatic until exposed to one of the triggers listed above. It is the commonest human enzyme defect and affects males more than females because of the X-linked inheritance pattern. The use of penicillins and cephalosporins is generally safe.
-
This question is part of the following fields:
- Haematology
- Pathology
-
-
Question 19
Incorrect
-
Regarding bile, which of the following statements is CORRECT:
Your Answer: Bile is synthesised in the gallbladder.
Correct Answer: Bile passes into the duodenum through the ampulla of Vater.
Explanation:Bile is synthesised in the liver. Bile functions to eliminate endogenous and exogenous substances from the liver, to neutralise gastric acid in the small intestine, and to emulsify fats in the small intestine and facilitate their digestion and absorption. Bile is stored and concentrated in the gallbladder. Bile passes out of the gallbladder via the cystic duct. Bile passes into the duodenum through the ampulla of Vater regulated by the sphincter of Oddi.
-
This question is part of the following fields:
- Gastrointestinal
- Physiology
-
-
Question 20
Incorrect
-
Where on the body is the radial artery pulsation best palpated?
Your Answer: At the wrist just lateral to the palmaris longus tendon
Correct Answer: At the wrist just lateral to the flexor carpi radialis tendon
Explanation:The radial artery lies lateral to the large tendon of the flexor carpi radialis muscle and anterior to the pronator quadratus at the distal end of the radius. The flexor carpi radialis muscle is used as a landmark in locating the pulse.
-
This question is part of the following fields:
- Anatomy
- Upper Limb
-
-
Question 21
Incorrect
-
The following statements about leukotrienes as chemical mediators of the acute inflammatory response are all true EXCEPT?
Your Answer: They sustain inflammatory actions in allergic reactions
Correct Answer: They decrease vascular permeability
Explanation:Leukotrienes increases (not decrease) vascular permeability during acute inflammation.
All the other statements are correct
-
This question is part of the following fields:
- General Pathology
- Pathology
-
-
Question 22
Correct
-
Cardiac myocytes are connected to each other by which of the following:
Your Answer: Intercalated discs
Explanation:Adjacent cardiac myocytes are connected to each other by intercalated discs. The intercalated discs provide both a structural attachment by ‘glueing’ cells together at desmosomes and an electrical contact made up of proteins called connexons, called a gap junction, which essentially creates a low-resistance pathway between cells.
-
This question is part of the following fields:
- Cardiovascular
- Physiology
-
-
Question 23
Correct
-
A patient who was put on low molecular weight heparin for suspected DVT and was scheduled for an ultrasound after the weekend, arrives at the emergency department with significant hematemesis. Which of the following medications can be used as a heparin reversal agent:
Your Answer: Protamine sulfate
Explanation:The management of bleeding in a patient receiving heparin depends upon the location and severity of bleeding, the underlying thromboembolic risk, and the current aPTT (for heparin) or anti-factor Xa activity (for LMW heparin). As an example, a patient with minor skin bleeding in the setting of a mechanical heart valve (high thromboembolic risk) and a therapeutic aPTT may continue heparin therapy, whereas a patient with major intracerebral bleeding in the setting of venous thromboembolism several months prior who is receiving heparin bridging perioperatively may require immediate heparin discontinuation and reversal with protamine sulphate. If haemorrhage occurs it is usually sufficient to withdraw unfractionated or low molecular weight heparin, but if rapid reversal of the effects of the heparin is required, protamine sulphate is a specific antidote (but only partially reverses the effects of low molecular weight heparins). Clinician judgment and early involvement of the appropriate consulting specialists is advised.
-
This question is part of the following fields:
- Cardiovascular
- Pharmacology
-
-
Question 24
Incorrect
-
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: IV diazepam is the first-line drug
Correct 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.
-
This question is part of the following fields:
- CNS Pharmacology
- Pharmacology
-
-
Question 25
Incorrect
-
Carbamazepine is contraindicated in which of the following:
Your Answer: Raised intracranial pressure
Correct Answer: Atrioventricular block
Explanation:Carbamazepine is contraindicated in:
– People with known hypersensitivity to carbamazepine or structurally related drugs
– People with atrioventricular block (may suppress AV conduction and ventricular automaticity)
– People with a history of bone marrow depression (risk of agranulocytosis and aplastic anaemia)
– People with a history of acute porphyrias
– People taking a monoamine oxidase inhibitor (risk of serotonin syndrome) -
This question is part of the following fields:
- Central Nervous System
- Pharmacology
-
-
Question 26
Correct
-
You see a patient in the ED with photophobia, petechial rash, headache and neck stiffness, and suspect a diagnosis of meningococcal meningitis.
What is the most appropriate initial management?
Your Answer: Give ceftriaxone 2 g IV
Explanation:Treatment should be commenced with antibiotics immediately before laboratory confirmation due to the potentially life-threatening nature of the disease.
In a hospital setting, 2g of IV ceftriaxone (80 mg/kg for a child) or IV cefotaxime (2 g adult; 80 mg/kg child) are the drugs of choice.
In the prehospital setting, IM benzylpenicillin can be given as an alternative. -
This question is part of the following fields:
- Microbiology
- Specific Pathogen Groups
-
-
Question 27
Correct
-
Which of the following features of cell damage tends to be reversible:
Your Answer: Swelling of endoplasmic reticulum and some mitochondria
Explanation:Features of cell damage that tend to be reversible include: swelling of endoplasmic reticulum and some mitochondrialoss of ribosomescell stress response
Features of cell damage that tend to be irreversible include: loss of nucleolus, no ribosomes, swelling of all mitochondria, nuclear condensation, membrane blebs and holes, lysosome rupture, fragmentation of all inner membranes, nuclear breakup -
This question is part of the following fields:
- Inflammatory Responses
- Pathology
-
-
Question 28
Incorrect
-
Clostridium difficile primarily causes which of the following infectious diseases:
Your Answer: Toxic shock syndrome
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.
-
This question is part of the following fields:
- Microbiology
- Pathogens
-
-
Question 29
Correct
-
A tumour is discovered behind the pectinate line during an examination of a 72-year-old patient with rectal bleeding. Which of the following is the lymphatic drainage of the pectinate line?
Your Answer: Superficial inguinal nodes
Explanation:The pectinate line is known as the watershed line because it divides the anal canal into two sections. Below the pectinate line, lymphatic drainage drains to the superficial inguinal lymph nodes.
-
This question is part of the following fields:
- Abdomen
- Anatomy
-
-
Question 30
Correct
-
A patient who shows symptoms of infection and is admitted under supervision of the medical team. The organism which caused this, is a Gram-negative bacterium, according to the culture. A penicillin therapy is suggested by the microbiologist.
Which of the penicillins listed below is the most effective against Gram-negative bacteria?Your Answer: Amoxicillin
Explanation:Amoxicillin and Ampicillin are more hydrophilic (broad-spectrum)Â penicillins than benzylpenicillin and phenoxymethylpenicillin. Because they may penetrate through gaps in the outer phospholipid membrane, they are effective against Gram-negative bacteria. Amoxicillin and Ampicillin are resistant to penicillinase-producing microbes.
Community-acquired pneumonia, otitis media, sinusitis, oral infections, and urinary tract infections are among the most prevalent conditions for which they are prescribed. The normal adult oral dose of Amoxicillin is 500 mg three times/day, which can be increased to 1 g three times/day if necessary. Ampicillin is given to adults in doses of 0.5-1 g every 6 hours.
-
This question is part of the following fields:
- Infections
- Pharmacology
-
-
Question 31
Correct
-
The following statements are not true of the flexor digiti minimi brevis, except?
Your Answer: It is situated on the radial border of abductor digiti minimi
Explanation:Flexor digiti minimi brevis muscle is located on the ulnar side of the palm, lying on the radial border of the abductor digiti minimi. Together with the abductor digiti minimi and opponens digiti minimi muscles, it forms the hypothenar eminence. The muscle is situated inferior and lateral to adductor digiti minimi muscle and superior and medial to opponens digiti minimi muscle. The proximal parts of flexor digiti minimi brevis and abductor digiti minimi muscles form a gap through which deep branches of the ulnar artery and ulnar nerve pass.
-
This question is part of the following fields:
- Anatomy
- Upper Limb
-
-
Question 32
Incorrect
-
A 53-year-old male has presented to your clinic with the complaint of a rash on his right forearm. On examination, you discover small reddish-purple spots on the skin measuring less than 2-3 mm. They do not blanch on applying pressure.
Which one of the following best fits the description given above?Your Answer: Macule
Correct Answer: Petechiae
Explanation:Petechiae are small red or purple spots on the skin measuring less than 3 mm, caused by minor haemorrhages which do not blanch on applying pressure.
Purpura measures between 3mm and 1 cm in diameter, while ecchymoses are greater than 1 cm in diameter. Both are caused due to haemorrhage.Erythema is the generalised redness of the skin.
A macule is a flat, discoloured area of the skin measuring less than 1 cm in diameter.
-
This question is part of the following fields:
- General Pathology
- Pathology
-
-
Question 33
Correct
-
You are reviewing a patient in the Emergency Department brought in by the ambulance team from a burning building. After examination, you decide to intubate the patient due to laryngeal oedema. The induction agent you are planning to use is propofol.
Which one of the following statements about this medicine is TRUE?Your Answer: It decreases cardiac output by approximately 20%
Explanation:Propofol is a short-acting anaesthetic that is thought to work by potentiating GABA and glycine. It induces anterograde amnesia and anaesthetic effects and is used to induce anaesthesia, outpatient surgeries and preoperative sedation. The dose for induction of anaesthesia is 1.5-2.5mg/kg. The dose for maintenance of anaesthesia is 4-12 mg/kg/hour. Following intravenous injection, propofol acts within 30 seconds and its duration of action is 5-10 minutes.
Propofol produces a 15-25% decrease in blood pressure and systemic vascular resistance without a compensatory increase in heart rate. It is negatively inotropic and decreases cardiac output by approximately 20%.
The main side effects of propofol are:
Pain on injection (in up to 30%)
Hypotension
Transient apnoea
Hyperventilation
Coughing and hiccough
Headache
Thrombosis and phlebitis -
This question is part of the following fields:
- Anaesthesia
- Pharmacology
-
-
Question 34
Correct
-
A 53 year old male is found to have megaloblastic anaemia secondary to folate deficiency. He has a known history of alcohol abuse. Which of the following is characteristic of this condition?
Your Answer: Increased mean corpuscular volume (MCV)
Explanation:Megaloblastic anaemia occurs when there is inhibition of DNA synthesis as red blood cells are produced. Impairment of DNA synthesis causes the cell cycle to be unable to progress from the growth stage to the mitosis stage. As a result, there is continuous cell growth without division, with an increase in mean corpuscular volume (MCV), which presents as macrocytosis. The most common cause of this defect in red cell DNA synthesis is hypovitaminosis, in particular, vitamin B12 deficiency or folate deficiency.
Folate is an essential vitamin that can be found in most foods, and is highest in liver, green vegetables and yeast. 200 – 250 μg is found in the normal daily diet, and about 50% is absorbed. The daily adult requirement is about 100 μg and its absorption is principally from the duodenum and jejunum. Folate stores are normally only adequate for 4 months and so clinical features of folate deficiency usually become evident after this time. -
This question is part of the following fields:
- Haematology
- Pathology
-
-
Question 35
Incorrect
-
Which of the following is NOT a typical cerebellar sign:
Your Answer: Scanning/staccato speech
Correct Answer: Hypertonia
Explanation:Hypotonia means decreased muscle tone. It can be a condition on its own, called benign congenital hypotonia, or it can be indicative of another problem where there is progressive loss of muscle tone, such as muscular dystrophy or cerebral palsy. It is usually detected during infancy. Hypotonia is characteristic of cerebellar dysfunction.
-
This question is part of the following fields:
- Anatomy
- Central Nervous System
-
-
Question 36
Correct
-
Which of the following best describes the therapeutic effect of calcium gluconate when used in treatment for hyperkalaemia:
Your Answer: Reduces cardiac cell membrane excitability
Explanation:Calcium resonium is an ion-exchange resin that exchanges sodium for potassium as it passes through the intestine, leading to excretion of potassium from the body. Salbutamol and insulin act to increase intracellular uptake of K+ via Na-K ATP pump. Sodium bicarbonate acts to correct acidosis and thus promotes intracellular uptake of K+. Calcium gluconate acts to protect the cardiac membrane and has no effect on serum K+ levels.
-
This question is part of the following fields:
- Fluids And Electrolytes
- Pharmacology
-
-
Question 37
Correct
-
A 33 year old female patient presents to emergency room with some symptoms that she thinks might be due to a drug that she has recently started. She was started on hyoscine butyl bromide for symptomatic relief of irritable bowel syndrome. The least likely expected side effect of this drug in this patient is:
Your Answer: Diarrhoea
Explanation:One of the commonest antispasmodic medications that is used is hyoscine butylbromide. It is an antimuscarinic and typical side effects of this class of drugs include:
– dilation of pupils with loss of accommodation (cycloplegia)
-photophobia resulting in blurred vision (Blind as a bat)
-dry mouth, eyes and skin (Dry as a bone),
-elevated temperature (Hot as a hare)
-skin flushing (Red as a beet)
-confusion or agitation particularly in the elderly (Mad as a hatter)
-reduced bronchial secretions
-transient bradycardia followed by tachycardia, palpitation and arrhythmias
-urinary retention and/or constipation -
This question is part of the following fields:
- Gastrointestinal
- Pharmacology
-
-
Question 38
Incorrect
-
The second generation antihistamine, cetirizine is a less-sedating antihistamine than the older antihistamine, chlorphenamine because:
Your Answer: It is metabolised more quickly by the liver.
Correct Answer: It is less lipid-soluble so less able to cross the blood brain barrier.
Explanation:All older antihistamines such as chlorphenamine cause sedation. The newer antihistamines e.g. cetirizine cause less sedation and psychomotor impairment than the older antihistamines because they are much less lipid soluble and penetrate the blood brain barrier only to a slight extent.
-
This question is part of the following fields:
- Pharmacology
- Respiratory
-
-
Question 39
Correct
-
Alpha cells of the endocrine pancreas produce which of the following hormones:
Your 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.
-
This question is part of the following fields:
- Endocrine
- Physiology
-
-
Question 40
Incorrect
-
Which of the following statements is correct regarding paracetamol?
Your Answer: Paracetamol can cause gastric irritation, particularly in the elderly.
Correct Answer: Liver damage peaks 3 to 4 days after paracetamol ingestion.
Explanation:The maximum daily dose of paracetamol in an adult is 4 grams. Doses greater than this can lead to hepatotoxicity and, less frequently, acute kidney injury. Early symptoms of paracetamol toxicity include nausea, vomiting, and abdominal pain, and usually settle within 24 hours. Symptoms of liver damage include right subcostal pain and tenderness, and this peaks 3 to 4 days after paracetamol ingestion. Other signs of hepatic toxicity include encephalopathy, bleeding, hypoglycaemia, and cerebral oedema.
-
This question is part of the following fields:
- Central Nervous System
- Pharmacology
-
-
Question 41
Correct
-
Cefotaxime (or ceftriaxone) is used first line for which of the following infections:
Your Answer: Blind treatment of suspected bacterial meningitis
Explanation:Cefotaxime (or ceftriaxone) are indicated first line in:
– Blind treatment of meningitis in patients > 3 months (with amoxicillin if patient > 50 years)
– Meningitis caused by meningococci
– Meningitis caused by pneumococci
– Meningitis caused by H. influenzae
– Severe or invasive salmonellosis
– Typhoid fever
– Gonorrhoea
– Gonococcal arthritis
– Haemophilus influenzae epiglottitis -
This question is part of the following fields:
- Infections
- Pharmacology
-
-
Question 42
Correct
-
Which of the following is NOT an adverse effect associated with warfarin therapy:
Your Answer: Neutropenia
Explanation:Adverse effects of warfarin:
The most common adverse effect of warfarin is bleedingOther common adverse effects of warfarin include nausea, vomiting, diarrhoea, jaundice, hepatic dysfunction, pancreatitis, pyrexia, alopecia, purpura, and rash
Skin necrosis is a rare but serious adverse effect of warfarin; treatment with warfarin should be stopped if warfarin related skin necrosis is suspected
Calciphylaxis is a rare, but a very serious condition that causes vascular calcification and cutaneous necrosis
-
This question is part of the following fields:
- Cardiovascular
- Pharmacology
-
-
Question 43
Correct
-
Which of the following conditions require IV Lidocaine administration?
Your Answer: Refractory ventricular fibrillation in cardiac arrest
Explanation:IV Lidocaine is indicated in Ventricular Arrhythmias or Pulseless Ventricular Tachycardia (after defibrillation, attempted CPR, and vasopressor administration)
-
This question is part of the following fields:
- Cardiovascular
- Pharmacology
-
-
Question 44
Correct
-
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: 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.
-
This question is part of the following fields:
- Anatomy
- Central Nervous System
-
-
Question 45
Correct
-
A patient is diagnosed as having a glucagonoma. Her blood serum glucagon concentration is 1246 pg/mL.
Glucagon is produced in which of the following cells? Select ONE answer only.Your Answer: Alpha-cells in the pancreas
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.
-
This question is part of the following fields:
- Endocrine Physiology
- Physiology
-
-
Question 46
Incorrect
-
Which of the following best describes the process of opsonisation:
Your Answer: Direct neutralisation of bacterial toxins and viruses by antibodies
Correct Answer: The coating of foreign particles with molecules which allow easier recognition of that cell by phagocytes
Explanation:An opsonin is any molecule that enhances phagocytosis by marking an antigen for an immune response, for example, immunoglobulin or complement. Opsonisation is the molecular mechanism whereby molecules, microbes, or apoptotic cells are chemically modified to have a stronger attraction to the cell surface receptors on phagocytes and natural killer cells. With the antigen coated in opsonins, binding to immune cells is greatly enhanced. Opsonisation also mediates phagocytosis via signal cascades from cell surface receptors.
-
This question is part of the following fields:
- Immune Responses
- Pathology
-
-
Question 47
Correct
-
Which of the following drugs decreases plasma-theophylline levels:
Your Answer: Carbamazepine
Explanation:Examples of enzyme-inhibiting drugs (raise plasma theophylline level):
Erythromycin
Clarithromycin
Ciprofloxacin
Fluconazole
Verapamil
Allopurinol
Cimetidine
Examples of enzyme-inducing drugs (lower plasma theophylline level):
Primidone
Phenobarbital
Carbamazepine
Phenytoin
Ritonavir
Rifampicin
St John’s Wort -
This question is part of the following fields:
- Pharmacology
- Respiratory
-
-
Question 48
Correct
-
Which of the following is NOT an adverse effect of amitriptyline:
Your Answer: Hypokalaemia
Explanation:Adverse effects include:
Antimuscarinic effects: Dry mouth, Blurred vision, Constipation, Urinary retention, Sedation, Confusion
Cardiovascular effects: Heart block, Arrhythmias, Tachycardia, Postural hypotension, QT-interval prolongation, Hepatic impairment, Narrow-angle glaucoma -
This question is part of the following fields:
- Central Nervous System
- Pharmacology
-
-
Question 49
Correct
-
Which of the following lifestyle changes is not likely to improve symptoms of gastro-oesophageal reflux disease (GORD):
Your Answer: Lowering the head of the bed
Explanation:The following approaches have some benefit in adult patients with reflux:
Weight loss or weight management for individuals who are overweight
Head of bed elevation is important for individuals with nocturnal or laryngeal symptoms, but its value for other situations is unclear.
The following lifestyle approaches also are used frequently. There is some evidence that these lifestyle changes improve laboratory measures of reflux (such as lower oesophageal sphincter pressure).
Dietary modification – A practical approach is to avoid a core group of reflux-inducing foods, including chocolate, peppermint, and alcohol, which may reduce lower oesophageal sphincter pressure. Acidic beverages, including colas with caffeine and orange juice also may exacerbate symptoms.
Avoiding the supine position soon after eating.
Promotion of salivation by either chewing gum or using oral lozenges. Salivation neutralizes refluxed acid, thereby increasing the rate of oesophageal acid clearance.
Avoidance of tobacco (including passive exposure to tobacco smoke) and alcohol. Nicotine and alcohol reduce lower oesophageal sphincter pressure, and smoking also diminishes salivation. -
This question is part of the following fields:
- Gastrointestinal
- Pharmacology
-
-
Question 50
Correct
-
A 55-year-old male diabetic patient presents to the Emergency Room complaining of severe chest pain. His medical record shows that he had coronary angioplasty one week ago, during which he was administered abciximab.
Which of the following haematological diseases has a similar mechanism of action to this drug?Your Answer: Glanzmann’s thrombasthenia
Explanation:Abciximab is glycoprotein IIb/IIIa receptor antagonist that decreases aggregation of platelets by prevent their cross-linking. In Glanzmann’s thrombasthenia there are low levels of these same receptors leading to decreased bridging of platelets as fibrinogen cannot attach. There is increased bleeding time both in this disease and when there is use of abciximab.
-
This question is part of the following fields:
- Cardiovascular Pharmacology
- Pharmacology
-
-
Question 51
Incorrect
-
Regarding the refractory period, which of the following statements is INCORRECT:
Your Answer: The relative refractory period is due to a temporary hyperpolarisation.
Correct Answer: Action potentials can occur in the relative refractory period but the amplitude of the action potential is smaller.
Explanation:Following the action potential, Na+channels remain inactive for a time in a period known as the absolute refractory period where they cannot be opened by any amount of depolarisation. Following this there is a relative refractory period where the temporary hyperpolarisation (due to delayed closure of rectifier K+channels) makes the cell more difficult to depolarise and an action potential can be generated only in response to a larger than normal stimulus. The refractory period limits the frequency at which action potentials can be generated, and ensures that, once initiated, an action potential can travel only in one direction. An action potential is an all or nothing response so the amplitude of the action potential cannot be smaller.
-
This question is part of the following fields:
- Basic Cellular
- Physiology
-
-
Question 52
Incorrect
-
Regarding pressures and airflow during the normal breathing cycle, which of the following statements is INCORRECT:
Your Answer: At rest, before inspiration begins, alveolar pressure equals atmospheric pressure.
Correct Answer: Negative intrapleural pressure causes dynamic compression of the airways.
Explanation:Dynamic compression occurs during forced expiration, when as the expiratory muscles contract, all the structures within the lungs, including the airways, are compressed by the positive intrapleural pressure. Consequently the smaller airways collapse before the alveoli empty completely and some air remains within the lungs (the residual volume).
-
This question is part of the following fields:
- Physiology
- Respiratory
-
-
Question 53
Incorrect
-
Which of the following best describes the order in which blood passes through the nephron?
Your Answer: Afferent arteriole→Glomerular capillary→Peritubular capillary→Efferent arteriole→Vasa recta
Correct Answer: Afferent arteriole→Glomerular capillary→Efferent arteriole→Peritubular capillary→Vasa recta
Explanation:The nephron’s blood flow is as follows:
Afferent arteriole – Glomerular capillary – Efferent arteriole – Peritubular capillary – Vasa recta – Afferent arteriole – Glomerular capillary – Efferent arteriole – Peritubular capillary – Vasa rectaThe kidney is the only vascular network in the body with two capillary beds. With arterioles supplying and draining the glomerular capillaries, higher hydrostatic pressures at the glomerulus are maintained, allowing for better filtration. A second capillary network at the tubules enables for secretion and absorption in the tubules, as well as concentrating urine.
-
This question is part of the following fields:
- Physiology
- Renal Physiology
-
-
Question 54
Incorrect
-
All of the following typically occurs as part of normal inspiration except:
Your Answer: Lateral movements of the ribs
Correct Answer: Contraction of the internal intercostal muscles
Explanation:Passive inspiration is a result of contraction of the diaphragm (depressing the diaphragm) and the external intercostal muscles (elevating the ribs).
In inspiration, several movements occur. These are:
1. elevation of the sternal ends of the ribs (‘pump handle’ movement),
2. elevation of the lateral shafts of the ribs (‘bucket handle’ movement)
3. depression of the diaphragm.
These result in expansion of the thorax in an anteroposterior, transverse and vertical direction respectively. There is an increased intrathoracic volume and decreased intrathoracic pressure and air is drawn into the lungs. -
This question is part of the following fields:
- Anatomy
- Thorax
-
-
Question 55
Correct
-
Which of the following is NOT an advantage of a case-control study used to identify past exposure to a risk factor in patients with a disease:
Your Answer: Can directly measure absolute and relative risk of a disease
Explanation:Advantages:relatively quickrelatively cheap and easy to performparticularly suitable for studying associations between an exposure and an outcome when the outcome is uncommon or if the outcome occurs decades after exposurea wide range of risk factors can be investigated in each studyDisadvantages:subject to recall biasunlike in a whole population study, absolute risk cannot be quantifiedtemporal relationship between exposure and outcome can be difficult to establishunsuitable for rare risk factorsprone to confounding
-
This question is part of the following fields:
- Evidence Based Medicine
- Study Methodology
-
-
Question 56
Correct
-
You suspect that your patient with polycystic kidney disease has developed a berry aneurysm as a complication of his disease. The patient complains of a sudden, severe headache. You are guessing subarachnoid haemorrhage secondary to a ruptured berry aneurysm as the cause of his severe headaches. What is the most likely location of his aneurysm?
Your Answer: Anterior communicating artery
Explanation:One of the complications that polycystic kidney disease may cause is the development of a brain aneurysm.
A berry aneurysm is the most common type of brain aneurysm.
The Circle of Willis, where the major blood vessels meet at the base of the brain, is where it usually appears. The most common junctions of the Circle of Willis where an aneurysm may occur include the anterior communicating artery (35%), internal carotid artery (30%), the posterior communicating artery and the middle cerebral artery (22%), and finally, the posterior circulation sites, most commonly the basilar artery tip.
-
This question is part of the following fields:
- Anatomy
- Central Nervous System
-
-
Question 57
Incorrect
-
A 56-year-old male with a 10-year history of Diabetes Mellitus and Hypertension was rushed to the Emergency Department due to sudden onset crushing chest pain. ECG showed an ST-elevation myocardial infarct in the left anterior descending artery territory. The patient's condition was stabilised and managed with angioplasty, but he sustained significant myocardial damage.
Which one of the following statements best agrees with the myocardial healing process?Your Answer: The cells of the anterior wall will undergo mitosis
Correct Answer: The left ventricle will likely hypertrophy first to maintain cardiac output
Explanation:Following a myocardial infarction scar tissue formation will take place at the site of the damaged muscle. This places increased load on the rest of the myocardium causing it to hypertrophy. The left ventricle will hypertrophy first as it is pumping blood against a greater afterload as compared to the right ventricle.
There are three types of cells in the body with regards to the cell cycle: 1. permanent
2. labile
3. stable cellsPermanent cells do not re-enter the cell cycle and remain in G0. If there is a pool of stem cells the stem cells will enter the cell cycle to form more cells. Myocardial cells are a type of permanent cell and there is no pool of stem cells in the heart muscle. The anterior wall will not hypertrophy as it is formed by the right atrium and ventricle and both of these hypertrophy after the left ventricle.
-
This question is part of the following fields:
- General Pathology
- Pathology
-
-
Question 58
Incorrect
-
A 29 year old woman is unable to invert her foot after sustaining an injury to her leg playing water-polo. Which of the following nerves are most likely damaged:
Your Answer: Tibial and saphenous nerve
Correct Answer: Tibial and deep fibular nerve
Explanation:Inversion of the foot is primarily produced by the tibialis anterior and the tibialis posterior muscles, innervated by the deep fibular nerve and the tibial nerve respectively.
-
This question is part of the following fields:
- Anatomy
- Lower Limb
-
-
Question 59
Correct
-
Which of the following is the primary indication for loop diuretics?
Your Answer: Acute pulmonary oedema
Explanation:Loop diuretics have long been the cornerstone of pulmonary oedema treatment, with furosemide being the most commonly used of these drugs. Premedication with drugs that decrease preload (e.g., nitro-glycerine [NTG]) and afterload (e.g., angiotensin-converting enzyme [ACE] inhibitors) before the administration of loop diuretics can prevent adverse hemodynamic changes.
-
This question is part of the following fields:
- Cardiovascular
- Pharmacology
-
-
Question 60
Correct
-
A patient who is a known case of rheumatoid arthritis presents to the clinic as his grandson was recently diagnosed with chickenpox. His grandson spent the weekend with her, and he was in close contact with him. He takes 50 mg of prednisolone once daily and has been for the past six months. There is no history of chickenpox.
Out of the following, which is TRUE regarding the next plan of action for her care?Your Answer: She should receive prophylactic varicella-zoster Immunoglobulin (VZIG)
Explanation:Varicella-zoster immunoglobulin (VZIG) is indicated for post exposure prevention and treatment of varicella. It is recommended as prophylaxis for high-risk patients with no known immunity (i.e. no known previous chickenpox) who have had a significant exposure to varicella-zoster (considered >4 hours close contact).
The high-risk groups are:
1. Neonates
2. Pregnant women
3. The immunocompromised (e.g. cancer, immunosuppressive therapies)
4. Those on high dose steroids (children on more than 2 mg/kg/day for more than 14 days, or adults on 40 mg/day for more than a week)This patient is at high risk of developing adrenal insufficiency and may need a temporary increase in her steroid dose during infection or stress. It would be inappropriate to stop or wean down her dose of prednisolone and can cause side effects.
Since he is on steroids without immunity for chickenpox, he is at risk of developing severe varicella infection, with possible complications including pneumonia, hepatitis and DIC.
If he develops a varicella infection, he will need to be admitted and require a specialist review and intravenous Acyclovir.
-
This question is part of the following fields:
- Immunological Products & Vaccines
- Pharmacology
-
-
Question 61
Incorrect
-
A 75-year-old man with rheumatoid arthritis had gained weight, developed resistant hypertension, muscle weakness, and ankle oedema. This patient is most likely suffering from what condition?
Your Answer: Pheochromocytoma
Correct Answer: Cushing's syndrome
Explanation:Overuse of cortisol medication, as seen in the treatment of patients with chronic asthma or rheumatoid arthritis, can cause Cushing’s syndrome.
Weight gain, thin arms and legs, a round face, increased fat around the base of the neck, a fatty hump between the shoulders, easy bruising, wide purple stretch marks primarily on the abdomen, breasts, hips, and under the arms, weak muscles, hirsutism, hypertension, erectile dysfunction, osteoporosis, frontal alopecia, acne, depression, poor wound healing, and polycythaemia are all clinical features of Cushing’s syndrome.
-
This question is part of the following fields:
- Endocrine
- Physiology
-
-
Question 62
Incorrect
-
Regarding bias, which of the following statements is CORRECT:
Your Answer: Bias is only important if the results of a study show an association between two variables.
Correct 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.
-
This question is part of the following fields:
- Evidence Based Medicine
- Study Methodology
-
-
Question 63
Incorrect
-
A 35-year-old man suffered a severe road traffic accident and has been brought to the hospital. As part of his treatment, he requires a blood transfusion and experiences a transfusion reaction.
The most common type of transfusion reaction is which of the following?Your Answer: Allergic reaction
Correct Answer: Febrile transfusion reaction
Explanation:During or shortly after transfusion, febrile transfusion reactions, also known as non-haemolytic transfusion reactions, present with an unexpected temperature rise (38oC or 1oC above baseline, if baseline is 37oC). This is usually a one-off occurrence. The fever is sometimes accompanied by chills.
The most common type of transfusion reaction is febrile transfusion reactions, which occur in about 1 in every 8 transfusions.
The most common event leading to symptoms of febrile transfusion reactions is cytokine accumulation during storage of cellular components (especially platelet units). White cells secrete cytokines, and pre-storage leucodepletion has reduced this risk.
Recipient antibodies (raised as a result of previous transfusions or pregnancies) reacting to donor human leukocyte antigen (HLA) or other antigens can also cause febrile transfusion reactions. Donor lymphocytes, granulocytes, and platelets all contain these antigens.
Treatment is reassuring. Other causes should be ruled out, and antipyretics like paracetamol can help with fever relief. If another cause of fever is suspected, the transfusion should be stopped; however, if other causes of fever have been ruled out, it can be restarted at a slower rate.
-
This question is part of the following fields:
- Haematology
- Pathology
-
-
Question 64
Correct
-
Which of the following clinical features is most suggestive of a lesion of the occipital lobe:
Your Answer: Homonymous hemianopia
Explanation:Homonymous hemianopia is a visual field defect involving either the two right or the two left halves of the visual fields of both eyes. It is caused by lesions of the retrochiasmal visual pathways, ie, lesions of the optic tract, the lateral geniculate nucleus, the optic radiations, and the cerebral visual (occipital) cortex
-
This question is part of the following fields:
- Anatomy
- Central Nervous System
-
-
Question 65
Incorrect
-
Approximately what proportion of lymphocytes are B-cells:
Your Answer: 0.5
Correct Answer: 0.2
Explanation:B-cells (20% of lymphocytes) mature in the bone marrow and circulate in the peripheral blood until they undergo recognition of antigen. B-cell immunoglobulin molecules synthesised in the cell are exported and bound to the surface membrane to become the B-cell receptor (BCR) which can recognise and bind to a specific antigen (either free or presented by APCs). The BCR is also important for antigen internalisation, processing and presentation to T helper cells. Most antibody responses require help from antigen-specific T helper cells (although some antigens such as polysaccharide can lead to T-cell independent B-cell antibody production). When the B-cell is activated, the receptor itself is secreted as free soluble immunoglobulin and the B-cell matures into a memory B-cell or a plasma cell (a B-cell in its high-rate immunoglobulin secreting state). Plasma cells are non-motile and are found predominantly in the bone marrow or spleen. Most plasma cells are short-lived (1 – 2 weeks) but some may survive much longer. A proportion of B-cells persist as memory cells, whose increased number and rapid response underlies the augmented secondary response of the adaptive immune system.
-
This question is part of the following fields:
- Immune Responses
- Pathology
-
-
Question 66
Correct
-
How is filtered K+mainly reabsorbed in the thick ascending limb of the loop of Henle:
Your Answer: Secondary active transport via Na + /K + /2Cl - cotransporter
Explanation:Around 30% of filtered K+is reabsorbed in the thick ascending limb of the loop of Henle, primarily via the luminal Na+/K+/2Cl-cotransporter, but there is also significant paracellular reabsorption, encouraged by the positive potential in the tubular lumen.
-
This question is part of the following fields:
- Physiology
- Renal
-
-
Question 67
Correct
-
All of the following statements are correct regarding penicillin antibiotics except:
Your Answer: Penicillins are of no use in meningitis as they are unable to penetrate into the cerebrospinal fluid.
Explanation:Penicillin penetration into the cerebrospinal fluid is generally poor. However, when the meninges are inflamed, as in meningitis, penetration of penicillin is increased. Benzylpenicillin should be given before transfer to hospital if meningococcal disease (meningitis with non-blanching rash or meningococcal septicaemia) is suspected, once this does not delay transfer.
Benzylpenicillin is no longer the drug of first choice for pneumococcal meningitis.
-
This question is part of the following fields:
- Infections
- Pharmacology
-
-
Question 68
Correct
-
A 29-year-old man has been complaining about his recent headaches. Detailed history was taken and a neurological examination was performed.
Which of the following cranial nerves is correctly paired with its lesion?Your Answer: The oculomotor nerve: the eye appears to look ‘down and out’
Explanation:The following are the lesions of the cranial nerves:
1. Olfactory nerve (I)
Reduced taste and smell, but not to ammonia which stimulates the pain fibres carried in the trigeminal nerve2. Optic nerve (II)
Manifested by visual field defects, pupillary abnormalities, optic neuritis, optic atrophy, papilledema3. Oculomotor nerve (III)
A fixed, dilated pupil which doesn’t accommodate, ptosis, complete internal ophthalmoplegia (masked by ptosis), unopposed lateral rectus causes outward deviation of the eye. If the ocular sympathetic fibres are also affected behind the orbit, the pupil will be fixed but not dilated.4. Trochlear nerve (IV)
Diplopia due to weakness of downward and inward eye movement. The most common cause of a pure vertical diplopia. The patient tends to compensate by tilting the head away from the affected side.5. Trigeminal nerve (V)
Reduced sensation or dysesthesia over the affected area. Weakness of jaw clenching and side-to-side movement. If there is a lower motor neuron (LMN) lesion, the jaw deviates to the weak side when the mouth is opened. There may be fasciculation of temporalis and masseter.6. Abducens nerve (VI)
Inability to look laterally. The eye is deviated medially because of unopposed action of the medial rectus muscle.7. Facial nerve (VII)
Facial weakness. In an LMN lesion the forehead is paralysed – the final common pathway to the muscles is destroyed; whereas the upper facial muscles are partially spared in an upper motor neurone (UMN) lesion because of alternative pathways in the brainstem. There appear to be different pathways for voluntary and emotional movement. CVAs usually weaken voluntary movement, often sparing involuntary movements (e.g., spontaneous smiling). The much rarer selective loss of emotional movement is called mimic paralysis and is usually due to a frontal or thalamic lesion.8. Vestibulocochlear nerve (VIII)
Unilateral sensorineural deafness, tinnitus. Slow-growing lesions seldom present with vestibular symptoms as compensation has time to occur.9. Glossopharyngeal nerve (IX)
Unilateral lesions do not cause any deficit because of bilateral corticobulbar connections. Bilateral lesions result in pseudobulbar palsy. These nerves are closely interlinked.10. Vagus nerve (X)
Palatal weakness can cause ‘nasal speech’ and nasal regurgitation of food. The palate moves asymmetrically when the patient says ‘ahh’. Recurrent nerve palsy results in hoarseness, loss of volume and ‘bovine cough’.11. Accessory nerve (XI)
Weakness and wasting of sternocleidomastoid and trapezius muscles12.Hypoglossal nerve (XII)
An LMN lesion produces wasting of the ipsilateral side of the tongue, with fasciculation; and on attempted protrusion the tongue deviates towards the affected side, but the tongue deviates away from the side of a central lesion. -
This question is part of the following fields:
- Anatomy
- Central Nervous System
-
-
Question 69
Incorrect
-
A 38-year-old woman presented to the emergency room after an incident of slipping and falling onto her back and left hip. Upon physical examination, it was noted that she has pain on hip flexion, but normal hip adduction. Which of the following muscles was most likely injured in this case?
Your Answer: Gracilis
Correct Answer: Sartorius
Explanation:The hip adductors are a group of five muscles located in the medial compartment of the thigh. These muscles are the adductor longus, adductor brevis, adductor magnus, gracilis, and pectineus.
The hip flexors consist of 5 key muscles that contribute to hip flexion: iliacus, psoas, pectineus, rectus femoris, and sartorius.
-
This question is part of the following fields:
- Anatomy
- Lower Limb
-
-
Question 70
Incorrect
-
A 50-year-old man has recently been on antibiotics for a chest infection. He suffers from COPD and is currently on Seretide inhalers, salbutamol, and Phyllocontin continus. Since commencing the antibiotics, he has developed nausea, vomiting and abdominal pain.
Which of the following antibiotics has he MOST LIKELY been on for his chest infection?Your Answer: Amoxicillin
Correct Answer: Erythromycin
Explanation:Phyllocontin continues contains aminophylline, a bronchodilator used in the management of asthma and COPD.
The index patient is exhibiting symptoms of theophylline toxicity. This may have been triggered by the antibiotic he took. Macrolide antibiotics, like erythromycin and quinolone antibiotics, like ciprofloxacin and levofloxacin, increases the plasma concentration of theophyllines and can lead to toxicity.
Factors that enhance theophylline clearance include cigarette smoking, carbamazepine, phenobarbital, phenytoin, primidone, and rifampin.
Medications that inhibit clearance include ethanol, ciprofloxacin, erythromycin, verapamil, propranolol, ticlopidine, tacrine, allopurinol, and cimetidine. -
This question is part of the following fields:
- Pharmacology
- Respiratory Pharmacology
-
-
Question 71
Incorrect
-
What is the partial pressure of oxygen if it makes up 20.9 percent of the ambient air composition and the atmospheric pressure of ambient air is 760 mmHg?
Your Answer: 30 mmHg
Correct Answer: 159 mmHg
Explanation:Ambient air is atmospheric air in its natural state. Ambient air is typically 78.6% nitrogen and 20.9% oxygen. The extra 1% is made up of carbon, helium, methane, argon and hydrogen.
The partial pressure of any gas can be calculated using this formula: P = atmospheric pressure (760 mmHg) x percent content in the mixture.
Atmospheric pressure is the sum of all of the partial pressures of the atmospheric gases added together: The formula for atmospheric pressure is: Patm = PN2 + PO2Â + PH2O + PCO2. The atmospheric pressure is known to be 760 mmHg.
The partial pressures of the various gases can be estimated to have partial pressures of approximately 597.4 mmHg for nitrogen, 158.8 mm Hg for oxygen, and 7.6 mmHg for argon.
-
This question is part of the following fields:
- Physiology
- Respiratory Physiology
-
-
Question 72
Correct
-
A 52-year-old man develops pneumonia 3 days following an admission for investigation of chest pain. He has coarse left basal crackles and evidence of consolidation in the left lower lobe of chest X-ray. He has no known drug allergies.
According to the latest NICE guidelines, which of the following antibacterial agents would be most appropriate to prescribe in this case? Select ONE answer only.Your Answer: Co-amoxiclav
Explanation:Nosocomial infections are defined as those occurring within 48 hours of hospital admission, 3 days of discharge or 30 days of an operation. They affect 1 in 10 patients admitted to hospital. Annually, this results in 5000 deaths with a cost to the National Health Service of a billion pounds. On average, a patient with hospital acquired infection spent 2.5-times longer in hospital, incurring additional costs of £3000 more than an uninfected patient. Intensive care units (ICU) have the highest prevalence of hospital-acquired infections in the hospital setting.
The current recommendations by NICE and the BNF on the treatment of hospital acquired pneumonia are:
Early onset infection(less than 5 days after admission to hospital): co-amoxiclav or cefuroxime for 7 days
Late-onset infection(more than 5 days after admission to hospital): an antipseudomonal penicillin (e.g. piperacillin with tazobactam), a broad-spectrum cephalosporin (e.g. ceftazidime), or a quinolone (e.g. ciprofloxacin)
If the patient developed a hospital-acquired pneumonia within 5 days of admission – co-amoxiclav would be the most appropriate choice.
If the patient has developed a hospital-acquired pneumonia > 5 days after admission – ciprofloxacin would be the most appropriate choice from the list of options available. -
This question is part of the following fields:
- Microbiology
- Principles Of Microbiology
-
-
Question 73
Incorrect
-
Regarding alteplase, which of the following statements is INCORRECT:
Your Answer: Alteplase must be given by continuous intravenous infusion.
Correct Answer: Alteplase is commonly associated with hypotensive effects.
Explanation:Alteplase is a recombinant tissue-type plasminogen activator (tPA), a naturally occurring fibrin-specific enzyme that has selectivity for activation of fibrin-bound plasminogen. It has a short half-life of 3 – 4Â minutes and must be given by continuous intravenous infusion but is not associated with antigenic or hypotensive effects, and can be used in patients when recent streptococcal infections or recent use of streptokinase contraindicates the use of streptokinase.
-
This question is part of the following fields:
- Cardiovascular
- Pharmacology
-
-
Question 74
Incorrect
-
Regarding NSAIDs, which of the following statements is CORRECT:
Your Answer: Mefenamic acid has very potent anti-inflammatory properties.
Correct Answer: Diclofenac is contraindicated in people with ischaemic heart disease.
Explanation:Due to their increased risk of cardiovascular adverse events, coxibs and diclofenac are contraindicated in people with ischaemic heart disease, cerebrovascular disease, peripheral arterial disease and mild, moderate, or severe heart failure. Other NSAIDs are only contraindicated in people with severe heart failure. Selective inhibition of COX-2 is associated with less gastrointestinal intolerance. In single doses NSAIDs have analgesic activity comparable to that of paracetamol, therefore given their side effect profile, paracetamol is preferred, particularly in the elderly. Pain relief starts soon after taking the first dose and a full analgesic effect should normally be obtained within a week, whereas an anti-inflammatory effect may not be achieved (or may not be clinically assessable) for up to 3 weeks. Mefenamic acid has only very mild anti-inflammatory properties.
-
This question is part of the following fields:
- Musculoskeletal
- Pharmacology
-
-
Question 75
Correct
-
Regarding haemoglobin, which of the following statements is CORRECT:
Your Answer: In degradation of haemoglobin, the haem group is split from the haemoglobin and converted to biliverdin and ultimately to bilirubin.
Explanation:Haemoglobin is composed of four polypeptide globin chains each with its own iron containing haem molecule. Haem synthesis occurs largely in the mitochondria by a series of biochemical reactions commencing with the condensation of glycine and succinyl coenzyme A under the action of the key rate-limiting enzyme delta-aminolevulinic acid (ALA) synthase. The globin chains are synthesised by ribosomes in the cytosol. Haemoglobin synthesis only occurs in immature red blood cells.
There are three types of haemoglobin in normal adult blood: haemoglobin A, A2 and F:
– Normal adult haemoglobin (HbA) makes up about 96 – 98 % of total adult haemoglobin, and consists of two alpha (α) and two beta (β) globin chains.Â
– Haemoglobin A2 (HbA2), a normal variant of adult haemoglobin, makes up about 1.5 – 3.5 % of total adult haemoglobin and consists of two α and two delta (δ) globin chains.
– Foetal haemoglobin is the main Hb in the later two-thirds of foetal life and in the newborn until approximately 12 weeks of age. Foetal haemoglobin has a higher affinity for oxygen than adult haemoglobin.Â
Red cells are destroyed by macrophages in the liver and spleen after , 120 days. The haem group is split from the haemoglobin and converted to biliverdin and then bilirubin. The iron is conserved and recycled to plasma via transferrin or stored in macrophages as ferritin and haemosiderin. An increased rate of haemoglobin breakdown results in excess bilirubin and jaundice. -
This question is part of the following fields:
- Basic Cellular
- Physiology
-
-
Question 76
Incorrect
-
Regarding gas exchange at the alveolar-capillary membrane, which of the following statements is CORRECT:
Your Answer: Gas exchange across the alveolar-capillary membrane occurs via diffusion from an area of low partial pressure to an area of high partial pressure.
Correct Answer: Transfer of oxygen is usually perfusion-limited.
Explanation:Gas exchange between alveolar air and blood in the pulmonary capillaries takes place by diffusion across the alveolar-capillary membrane. Diffusion occurs from an area of high partial pressure to an area of low partial pressure, thus the driving force for diffusion is the alveolar-capillary partial pressure gradient. Diffusion occurs until equilibrium is reached, but random movement of particles continues to occur and this is known as dynamic equilibrium. The diffusing capacity for oxygen (DLO2) cannot be measured directly but the rate of diffusion in the lungs can be estimated by measuring the diffusing capacity of the lungs for carbon monoxide (DLCO), not by measuring total lung capacity. The rate of transfer of a gas may be diffusion or perfusion limited; carbon monoxide transfer is diffusion-limited, oxygen transfer is usually perfusion-limited.
-
This question is part of the following fields:
- Physiology
- Respiratory
-
-
Question 77
Correct
-
In which of the following cases is intravenous phenytoin contraindicated?
Your Answer: Second degree heart block
Explanation:Phenytoin Contraindications include:
Hypersensitivity
Sinus bradycardia
Sinoatrial block
Second and third degree A-V block
Adams-Stokes syndrome
Concurrent use with delavirdine
History of prior acute hepatotoxicity attributable to phenytoin -
This question is part of the following fields:
- Central Nervous System
- Pharmacology
-
-
Question 78
Correct
-
A 29-year-old woman presents with night sweats, fever, and haemoptysis. A diagnosis of tuberculosis was suspected.
Which of the following statements regarding the diagnosis of tuberculosis is considered correct?Your Answer: Mycobacteria tuberculosis can be typed using a RFLP method
Explanation:Although a variety of clinical specimens may be submitted to the
laboratory to recover MTB and NTM, respiratory secretions such
as sputum and bronchial aspirates are the most common. An
early-morning specimen should be collected on three consecutive
days, although recent studies have suggested that the addition of
a third specimen does not significantly increase the sensitivity
of detecting Mycobacteria.Mycobacterium tuberculosis appear red on acid-fast staining because they take up the primary stain, which is carbolfuchsin, and is not decolorized by the acid alcohol anymore.
Culture on Lowenstein-Jensen medium should be read within 5 to 7 days after inoculation and once a week thereafter for up to 8 weeks.
Nucleic acid amplification assays designed to detect M. tuberculosis complex
bacilli directly from patient specimens can be performed in as little as 6 to 8 hours on processed specimens. -
This question is part of the following fields:
- Microbiology
- Specific Pathogen Groups
-
-
Question 79
Correct
-
Question 80
Incorrect
-
Which of the following is NOT a typical feature of lithium toxicity:
Your Answer: Hyperreflexia
Correct Answer: Miosis
Explanation:Features of toxicity include:
Increasing gastrointestinal disturbances (vomiting, diarrhoea, anorexia)
Visual disturbances
Polyuria and incontinence
Muscle weakness and tremor
Tinnitus
CNS disturbances (dizziness, confusion and drowsiness increasing to lack of coordination, restlessness, stupor)
Abnormal reflexes and myoclonus
Hypernatraemia
With severe overdosage (serum-lithium concentration > 2 mmol/L) seizures, cardiac arrhythmias (including sinoatrial block, bradycardia and first-degree heart block), blood pressure changes, electrolyte imbalance, circulatory failure, renal failure, coma and sudden death may occur. -
This question is part of the following fields:
- Central Nervous System
- Pharmacology
-
-
Question 81
Incorrect
-
A 29-year-old volunteer returns from a recent trip to the middle east with profuse watery diarrhoea. You make a diagnosis of cholera and organize a hospital admission for rehydration with intravenous fluids.
What is the mechanism of action of cholera toxin?
Your Answer: Inhibition of the enzyme phosphodiesterase
Correct Answer: ADP-ribosylation of the G regulatory protein
Explanation:Cholera is caused by Vibrio cholerae, a motile, Gram-negative, curved bacillus. It is transmitted through water and food (especially seafood) and is primarily a disease seen in developing countries where there is poor sanitation and lack of safe water supplies.
The cholera toxin leads to stimulation of adenyl cyclase, ADP-ribosylation of the G regulatory protein, inactivation of GTPase leading to active outpouring of NaCl.
The cholera toxin consists of an A (the toxin) and B subunit. The B subunit attaches to the gut mucosa and presents the A subunit to the cell. The toxin stimulates adenyl cyclase by irreversible ADP-ribosylation of the GTP binding domain of adenyl cyclase leading to the opening of chloride channels resulting in an outpouring of NaCl and water into the lumen of the gut and causing secretory diarrhoea.
Incubation period is between 2 and 5 days, but can be as short as just a few hours.
-
This question is part of the following fields:
- Microbiology
- Principles Of Microbiology
-
-
Question 82
Incorrect
-
Contraction of the diaphragm results in which of the following effects:
Your Answer: Elevation of the diaphragm
Correct Answer: Increased vertical dimension of the thorax
Explanation:Contraction of the diaphragm (as in inspiration) results in flattening (depression) of the diaphragm with an increase in vertical dimension of the thorax. This results in decreased intrathoracic pressure and increased intra-abdominal pressure.
-
This question is part of the following fields:
- Anatomy
- Thorax
-
-
Question 83
Incorrect
-
A 40-year-old male visits his family physician with the complaint of a high-grade fever for the past five days. A complete blood count report shows the presence of neutrophilia.
Which one of the following facts regarding neutrophilia is accurate?Your Answer: It is typically caused by typhoid fever
Correct Answer: It can be caused by eclampsia
Explanation:A total neutrophil count of greater than 7.5 x 109/L is called neutrophilia. Typhoid fever usually causes leukopenia or neutropenia. Both localised and generalised bacterial infections can cause neutrophilia.
Metabolic disorders such as
– gout
– eclampsia
– uraemia
can also cause neutrophilia.Acute neutrophilia, in which immature neutrophils can be seen, is referred to as a left shift and can be seen in conditions such as appendicitis.
-
This question is part of the following fields:
- Haematology
- Pathology
-
-
Question 84
Correct
-
Which of the following nerves provides cutaneous innervation to the posterior surface of the scrotum?
Your Answer: Branch of the perineal nerve
Explanation:The following nerves provide cutaneous innervation to the scrotum, and other anatomic structures:
The perineal nerve supplies the muscles in the urogenital triangle, and the skin on the posterior surface of the scrotum (or labia majora).
The genital branch of the genitofemoral nerve supplies the cremaster muscle, the skin over the anterior surface of the thigh, and the anterolateral surface of the scrotum.
The ilioinguinal nerve supplies the external oblique, internal oblique, transversus abdominis, skin of the upper medial aspect of thigh, the root of the penis and the anterior surface of the scrotum in the male, and the mons pubis and labia majora in the female.
The posterior cutaneous nerve of the thigh, or posterior femoral cutaneous nerve, supplies the skin over the lower medial quadrant of the buttock, the inferior skin of the scrotum or labium majus, and the back of the thigh and the upper part of the leg.
-
This question is part of the following fields:
- Abdomen And Pelvis
- Anatomy
-
-
Question 85
Incorrect
-
Gastrin release from antral G-cells is stimulated by all but which one of the following:
Your Answer: Vagal stimulation
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
-
-
Question 86
Incorrect
-
Renal potassium excretion is promoted by all but which one of the following:
Your Answer: Metabolic alkalosis
Correct Answer: Increased intracellular magnesium
Explanation:Aldosterone: A rise in [K+] in the extracellular fluid of the adrenal cortex directly stimulates aldosterone release. Aldosterone promotes the synthesis of Na+/K+ATPases and the insertion of more Na+/K+ATPases into the basolateral membrane, and also stimulates apical sodium and potassium channel activity, overall acting to increase sodium reabsorption and potassium secretion.
pH changes: Potassium secretion is reduced in acute acidosis and increased in acute alkalosis. A higher pH increases the apical K+channel activity and the basolateral Na+/K+ATPase activity – both changes that promote K+secretion.
Flow rates: Increased flow rates in the collecting duct reduce K+concentration in the lumen and therefore enhance K+secretion. Increased flow also activates BK potassium channels, and ENaC channels which promote potassium secretion and sodium reabsorption respectively.
Sodium delivery: Decreased Na+delivery to the collecting ducts results in less Na+reabsorption and hence a reduced gradient for K+secretion.
Magnesium: Intracellular magnesium can bind and block K+channels inhibiting K+secretion into the tubules. Therefore magnesium deficiency reduces this inhibitory effect and so allows more potassium to be secreted into tubules and can cause hypokalaemia. -
This question is part of the following fields:
- Physiology
- Renal
-
-
Question 87
Correct
-
A 5-year-old girl presents in a paediatric clinic with symptoms of viral gastroenteritis. You encourage the mother to treat the child at home with oral rehydration therapy (ORT), e.g. dioralyte.
Out of the following, which statement is FALSE regarding the use of ORT in the management of gastroenteritis?Your Answer: ORT is sugar-free
Explanation:One of the major complications of gastroenteritis is dehydration. Choosing the correct fluid replacement therapy is essential according to a patient’s hydration status.
Oral rehydration therapy (ORT) refers to the restitution of water and electrolyte deficits in dehydrated patients using an oral rehydration salt (ORS) solution. It is a fluid replacement strategy that is less invasive than other strategies for fluid replacement and has successfully lowered the mortality rate of diarrhoea in developing countries.
Some characteristics of Oral rehydration solutions are:
– slightly hypo-osmolar (about 250 mmol/litre) to prevent the possible induction of osmotic diarrhoea.
– contain glucose (e.g. 90 mmol/L in dioralyte). The addition of glucose improves sodium and water absorption in the bowel and prevents hypoglycaemia.
– also contains essential mineral saltsCurrent NICE guidance recommends that 50 ml/kg is given over 4 hours to treat mild dehydration.
Once rehydrated, a child should continue with their usual daily fluid intake plus 200 ml ORT after each loose stool. In an infant, give ORT at 1-1.5 x the normal feed volume and in an adult, give 200-400 ml after each loose stool. -
This question is part of the following fields:
- Fluids & Electrolytes
- Pharmacology
-
-
Question 88
Correct
-
Which of the following statements accurately describes the flexor digitorum superficialis muscle?
Your Answer: It flexes the middle phalanges of the medial four fingers at the proximal interphalangeal joints
Explanation:Flexor digitorum superficialis is the largest muscle of the anterior compartment of the forearm. It belongs to the superficial flexors of the forearm, together with pronator teres, flexor carpi radialis, flexor carpi ulnaris and palmaris longus. Some sources alternatively classify this muscle as an independent middle/intermediate layer of the anterior forearm, found between the superficial and deep groups.
Flexor digitorum superficialis is innervated by muscular branches of the median nerve, derived from roots C8 and T1 that arises from the medial and lateral cords of the brachial plexus. The skin that overlies the muscle is supplied by roots C6-8 and T1.
The primary arterial blood supply to the flexor digitorum superficialis is derived from the ulnar artery and its anterior recurrent branch. In addition to branches of the ulnar artery, the anterior and lateral surfaces of the muscle are supplied by branches of the radial artery; and its posterior surface also receives branches from the median artery.
The main function of flexor digitorum superficialis is flexion of the digits 2-5 at the proximal interphalangeal and metacarpophalangeal joints. Unlike the flexor digitorum profundus, flexor digitorum superficialis has independent muscle slips for all four digits. This allows it to flex the digits individually at their proximal interphalangeal joints. In addition, flexor digitorum superficialis aids the aids flexion of the wrist.
-
This question is part of the following fields:
- Anatomy
- Upper Limb
-
-
Question 89
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: Asthma
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.
-
This question is part of the following fields:
- Gastrointestinal
- Pharmacology
-
-
Question 90
Incorrect
-
Antinuclear antibodies (ANAs) also referred to as anti-nuclear factors (ANFs) are autoantibodies that bind to contents of the cell nucleus.
Which ONE of these statements about ANAs is true?Your Answer: ELISA is the most reliable method for testing
Correct Answer: They can be of any immunoglobulin class
Explanation:Anti-nuclear antibodies(ANAs) also referred to as anti-nuclear factors (ANFs) are autoantibodies that bind to contents of the cell nucleus. They can be of any immunoglobulin class.
CREST syndrome is usually associated with anti-centromere antibodies.
ELISA testing is cheaper but not the most accurate means of testing for ANAs. Indirect immunofluorescence testing is the most reliable.
Nucleolar staining is suggestive of scleroderma, while homogenous staining is suggestive of lupus.
Anti-dsDNA antibodies are found in 80 – 90% of patients with SLE
-
This question is part of the following fields:
- General Pathology
- Pathology
-
-
Question 91
Incorrect
-
Regarding water and electrolyte absorption in the small intestine, which of the following statements is INCORRECT:
Your Answer: K+ leaves the cell across the basolateral membrane down its concentration gradient linked to an outward movement of Cl-.
Correct Answer: Na+ enters the cell across the apical membrane against its concentration gradient by both membrane channels and transporter protein mechanisms.
Explanation:As the contents of the intestine are isotonic with body fluids and mostly have the same concentration of the major electrolytes, their absorption is active. Water cannot be moved directly, but follows osmotic gradients set up by the transport of ions, primarily mediated by the sodium pump.Na+/K+ ATPase located on the basolateral membrane of the epithelial cells pumps three Na+ ions from the cell in exchange for two K+ ions, against their respective concentration gradients. This leads to a low intracellular concentration of Na+ and a high intracellular concentration of K+. The low intracellular concentration of Na+ ensures a movement of Na+ from the intestinal contents into the cell down its concentration gradient by both membrane channels and transporter protein mechanisms. Na+ is then rapidly pumped again by the basolateral sodium pump. K+ leaves the cell across the basolateral membrane down its concentration gradient linked to an outward movement of Cl- against its concentration gradient (Cl- having entered the cell across the luminal membrane down its concentration gradient).
-
This question is part of the following fields:
- Gastrointestinal
- Physiology
-
-
Question 92
Correct
-
By what mechanism does Vibrio cholerae causes diarrhoea?
Your 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.
-
This question is part of the following fields:
- Gastrointestinal
- Physiology
-
-
Question 93
Correct
-
A patient with a history of worsening chronic breathlessness on exertion undergoes lung function testing. The results demonstrate an FEV 1 that is 58% predicted and an FEV 1 /FVC ratio less than 0.7.
Which of the following is the most likely diagnosis? Select ONE answer only.Your Answer: COPD
Explanation:Obstructive lung disorders are characterised by airway obstruction. Many obstructive diseases of the lung result from narrowing of the smaller bronchi and larger bronchioles, often because of excessive contraction of the smooth muscle itself.
In obstructive lung disease, FEV1is reduced to <80% of normal and FVC is usually reduced but to a lesser extent than FEV1. The FEV1/FVC ratio is reduced to <0.7.
Types of obstructive lung disorders include:
Chronic obstructive pulmonary disease (COPD)
Asthma
Bronchiectasis -
This question is part of the following fields:
- Physiology
- Respiratory Physiology
-
-
Question 94
Incorrect
-
Which of the following is NOT a typical effect caused by adrenaline:
Your Answer: Vasoconstriction of vessels in skin, mucous membranes and splanchnic bed
Correct Answer: Bronchoconstriction
Explanation:Actions of adrenaline:
Cardiovascular system
– Increased rate and force of cardiac contraction
– Vasoconstriction of vessels in skin, mucous membranes and splanchnic bed
– Vasodilation of skeletal muscle vessels
– Increased cardiac output and blood pressure
Respiratory system
– Bronchodilation
– Increased ventilation rate
Gastrointestinal system
– Smooth muscle relaxation
– Contraction of sphincters
– Metabolism
– Decreased insulin release
– Increased glucagon release
– Increased thermogenesis
– Increased glycolysis
– Increased lipolysis
Eye
– Pupillary dilation -
This question is part of the following fields:
- Endocrine
- Physiology
-
-
Question 95
Incorrect
-
Which of the following clinical features would you least expect to see in a lesion of the frontal lobe:
Your Answer: Inability to problem solve
Correct Answer: Contralateral homonymous hemianopia with macular sparing
Explanation:Contralateral homonymous hemianopia with macular sparing results from damage to the primary visual cortex of the occipital lobe. Incontinence may occur due to damage of the cortical micturition centre in the prefrontal cortex. Primitive reflexes and inability to problem solve may occur due to damage to the prefrontal cortex. Motor weakness of the contralateral limb with UMN signs may occur due to damage of the primary motor cortex.
-
This question is part of the following fields:
- Anatomy
- Central Nervous System
-
-
Question 96
Incorrect
-
Regarding fluid balance, which of the following statements is CORRECT:
Your Answer: An average adult male contains about 60 L of water in total.
Correct Answer: About three-quarters of extracellular fluid is interstitial.
Explanation:An ‘average’ person (70 kg male) contains about 40 litres of water in total, separated into different fluid compartments by biological semipermeable membranes; plasma cell membranes between extracellular and intracellular fluid, and capillary walls between interstitial and intravascular fluid. Around two-thirds of the total fluid (27 L) is intracellular fluid (ICF) and one-third of this (13 L) is extracellular fluid (ECF). The ECF can be further divided into intravascular fluid (3.5 L) and interstitial fluid (9.5 L).
Transcellular fluid refers to any fluid that does not contribute to any of the main compartments but which are derived from them e.g. gastrointestinal secretions and cerebrospinal fluid, and has a collective volume of approximately 2 L.
Osmosis is the passive movement of water across a semipermeable membrane from regions of low solute concentration to those of higher solute concentration. -
This question is part of the following fields:
- Basic Cellular
- Physiology
-
-
Question 97
Correct
-
AÂ patient had a left Colles' fracture, which you were able to repair. It was their second fragility fracture this year, and you'd like to provide them some tips on how to keep their bones healthy.
What percentage of the calcium in the body is kept in the bones? Only ONE response is acceptable.Your Answer: 99%
Explanation:Calcium is stored in bones for nearly all of the body’s calcium, but it is also found in some cells (most notably muscle cells) and the blood. The average adult diet comprises roughly 25 mmol of calcium per day, of which the body absorbs only about 5 mmol.
-
This question is part of the following fields:
- Endocrine Physiology
- Physiology
-
-
Question 98
Incorrect
-
A man presents to the emergency department with an injury that has damaged the opponens pollicis muscle.
Which of the following statements regarding the opponens pollicis muscle is considered correct?Your Answer: It assists with the abduction of the thumb
Correct Answer: It flexes the first metacarpal bone at the carpometacarpal joint
Explanation:Opponens pollicis is a muscle of thenar eminence, it is triangular in shape and lies deep to flexor pollicis brevis and abductor pollicis brevis. It originates from the flexor retinaculum, tubercles of scaphoid and trapezium, abductor pollicis longus tendon.
Its insertion is in the radial side of the base of proximal phalanx of thumb. It is supplied by the median nerve (C8, T1). It receives blood supply from superficial arch.
It flexes the metacarpal bone medially across the palm, also rotating it medially, causing opposition, the palmar aspect of the terminal segment of thumb contacts the flexor aspects of any other digit.
-
This question is part of the following fields:
- Anatomy
- Upper Limb
-
-
Question 99
Incorrect
-
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: Palmar digital branch of median nerve
Correct 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.
-
This question is part of the following fields:
- Anatomy
- Upper Limb
-
-
Question 100
Incorrect
-
Where is angiotensin I primarily converted to angiotensin II:
Your Answer: Liver
Correct Answer: Lungs
Explanation:Angiotensin I is converted to angiotensin II by the removal of two C-terminal residues by the enzyme angiotensin-converting enzyme (ACE). This primarily occurs in the lungs, although it does also occur to a lesser degree in endothelial cells and renal epithelial cells.
The main actions of angiotensin II are:
Vasoconstriction of vascular smooth muscle (resulting in increased blood pressure)
Vasoconstriction of the efferent arteriole of the glomerulus (resulting in an increased filtration fraction and preserved glomerular filtration rate)
Stimulation of aldosterone release from the zona glomerulosa of the adrenal cortex
Stimulation of anti-diuretic hormone (vasopressin) release from the posterior pituitary
Stimulation of thirst via the hypothalamus
Acts on the Na+/H+ exchanger in the proximal tubule of the kidney to stimulate Na+reabsorption and H+excretion -
This question is part of the following fields:
- Physiology
- Renal
-
SESSION STATS - PERFORMANCE PER SPECIALTY
