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NZREX Clinical practice questions

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Question 1Medicine

A 58-year-old man presents with sudden onset of severe tearing chest pain radiating to the back. His blood pressure is 180/100 mmHg in the right arm and 140/85 mmHg in the left arm. Which is the most appropriate initial imaging investigation for suspected acute aortic dissection in a haemodynamically stable patient?

  1. Contrast-enhanced CT angiography of the aorta Correct answer.
  2. Exercise stress testing
  3. Transthoracic echocardiography
  4. Plain chest radiograph

Explanation

Contrast-enhanced CT angiography is the first-line investigation for suspected acute aortic dissection in a stable patient, with high sensitivity and specificity for identifying the intimal flap and extent of dissection. Transthoracic echocardiography is limited in visualising the distal aorta and is used mainly in unstable patients or when CT is unavailable.

Question 2Medicine

A 24-year-old woman has recurrent episodes of palpitations, sweating and tremor relieved by eating. Which single laboratory test is the most appropriate initial screen for suspected insulinoma during a supervised fast?

  1. Serum cortisol at 9 am
  2. Serum thyrotropin (TSH)
  3. Fasting plasma glucose with simultaneous insulin and C-peptide Correct answer.
  4. Plasma metanephrines

Explanation

The diagnostic hallmark of insulinoma is Whipple's triad with inappropriately elevated insulin and C-peptide during documented hypoglycaemia. Measuring glucose simultaneously with insulin and C-peptide during a supervised fast confirms endogenous hyperinsulinaemia.

Question 3Medicine

A 70-year-old man with atrial fibrillation has a CHA2DS2-VASc score of 4. He has no contraindications to anticoagulation. Which is the most appropriate long-term strategy to reduce his stroke risk?

  1. No antithrombotic therapy
  2. Aspirin 75 mg daily alone
  3. Clopidogrel 75 mg daily alone
  4. Oral anticoagulation with a direct oral anticoagulant or warfarin Correct answer.

Explanation

A CHA2DS2-VASc score of 2 or more in men indicates sufficient stroke risk to warrant oral anticoagulation. Either a direct oral anticoagulant or warfarin is appropriate, with DOACs generally preferred unless contraindicated.

Question 4Medicine

A 32-year-old woman presents with a 3-week history of polyuria, polydipsia and weight loss. Capillary glucose is 22 mmol/L and urine ketones are positive. Which is the most appropriate first step in management?

  1. Oral metformin and outpatient review
  2. Intravenous fluid resuscitation with 0.9% sodium chloride and a fixed-rate intravenous insulin infusion Correct answer.
  3. Restriction of oral fluids to reduce polyuria
  4. Subcutaneous insulin sliding scale alone

Explanation

This presentation is diabetic ketoacidosis, a medical emergency requiring intravenous fluid resuscitation and a fixed-rate intravenous insulin infusion with electrolyte monitoring. Subcutaneous insulin is inadequate in the acute phase because of poor absorption and the need for continuous suppression of ketogenesis.

Question 5Medicine

A 45-year-old man has a 6-month history of early morning stiffness lasting over an hour, symmetrical small joint swelling and a positive rheumatoid factor. Which is the most appropriate first-line disease-modifying therapy?

  1. Prednisone monotherapy
  2. Colchicine
  3. Methotrexate Correct answer.
  4. Allopurinol

Explanation

Methotrexate is the anchor first-line disease-modifying antirheumatic drug for rheumatoid arthritis because it reduces joint damage and disease activity. Glucocorticoids may be used as bridging therapy but are not a disease-modifying first-line strategy.

Question 6Medicine

A 28-year-old woman has a 4 cm simple ovarian cyst found incidentally. She is asymptomatic with normal tumour markers. Which is the most appropriate management?

  1. Immediate laparoscopic oophorectomy
  2. Urgent referral to gynaecological oncology for staging
  3. Conservative observation with repeat ultrasound Correct answer.
  4. Systemic chemotherapy

Explanation

Simple ovarian cysts under 5 cm in a premenopausal woman with normal tumour markers are almost always benign and can be managed with observation and repeat ultrasound. Surgery is reserved for cysts that enlarge, become complex, or cause symptoms.

Question 7Medicine

A 3-year-old child is brought in with a barking cough, inspiratory stridor and a hoarse voice following a coryzal illness. He is not drooling and has no trismus. Which is the most likely diagnosis?

  1. Bacterial tracheitis
  2. Croup (laryngotracheobronchitis) Correct answer.
  3. Epiglottitis
  4. Foreign body aspiration

Explanation

Croup presents with a barking cough, inspiratory stridor and hoarseness after a viral upper respiratory infection, and is the commonest cause of acute stridor in young children. The absence of drooling and toxicity makes epiglottitis less likely.

Question 8Medicine

A 62-year-old woman has a serum sodium of 122 mmol/L after starting a thiazide diuretic. She is asymptomatic with normal neurological examination. Which is the most appropriate initial management?

  1. Fluid restriction alone without stopping the diuretic
  2. Demeclocycline therapy
  3. Stop the thiazide and restrict free water while monitoring serum sodium Correct answer.
  4. Rapid correction with hypertonic 3% saline

Explanation

Thiazide-induced hyponatraemia is managed by withdrawing the offending drug and restricting free water, with careful monitoring of serum sodium to avoid over-rapid correction. Hypertonic saline is reserved for severe symptomatic hyponatraemia or seizures.

Question 9Medicine

A 55-year-old man with a 40 pack-year smoking history presents with haemoptysis, weight loss and a right upper lobe mass with ipsilateral Horner's syndrome. Which histological type of lung cancer is most likely?

  1. Squamous cell carcinoma
  2. Small cell carcinoma
  3. Carcinoid tumour
  4. Adenocarcinoma Correct answer.

Explanation

An upper-lobe mass with ipsilateral Horner's syndrome suggests a superior sulcus (Pancoast) tumour involving the sympathetic pathway. Adenocarcinoma is the most frequent histology in contemporary series. This anatomical syndrome does not establish histology in an individual patient; biopsy is required.

Question 10Medicine

A 34-year-old woman with known epilepsy is 10 weeks pregnant and has been seizure-free for 2 years on sodium valproate. Which is the most appropriate action regarding her antiepileptic medication?

  1. Stop all antiepileptic medication immediately
  2. Switch to phenytoin empirically
  3. Continue sodium valproate at the current dose without change
  4. Refer for specialist review to consider switching to a lower-risk antiepileptic before pregnancy progresses Correct answer.

Explanation

Sodium valproate carries the highest risk of major congenital malformations and neurodevelopmental harm, and women of childbearing age should be reviewed by a specialist to consider switching to a lower-risk agent such as lamotrigine or levetiracetam. Abrupt withdrawal risks status epilepticus.

Question 11Medicine

A 68-year-old man has a blood pressure of 168/96 mmHg on three separate visits despite lifestyle measures. He has no diabetes, renal disease or cardiovascular disease. Which is the most appropriate initial pharmacological therapy?

  1. Combination of three antihypertensives simultaneously
  2. Immediate referral for renal denervation
  3. A thiazide-like diuretic, calcium channel blocker or ACE inhibitor as monotherapy Correct answer.
  4. No treatment until blood pressure exceeds 180/110 mmHg

Explanation

Stage 2 hypertension without compelling indications is managed with a single first-line agent from the classes of thiazide-like diuretics, calcium channel blockers or ACE inhibitors/ARBs, with combination therapy added if control is inadequate.

Question 12Medicine

A 19-year-old student presents with a 2-day history of fever, severe headache, photophobia and neck stiffness. He is alert with no focal neurology. Which is the most appropriate immediate action?

  1. Administer intravenous antibiotics promptly and arrange urgent lumbar puncture and blood cultures Correct answer.
  2. Arrange an outpatient MRI brain in one week
  3. Give oral paracetamol and discharge with safety-netting advice
  4. Start antiviral therapy only after CSF results are available

Explanation

Suspected bacterial meningitis requires prompt empirical intravenous antibiotics, ideally within an hour of presentation, before or alongside urgent investigations. Lumbar puncture and blood cultures should follow without delaying antibiotics.

Question 13Medicine

A 47-year-old woman has a thyroid nodule. Fine-needle aspiration cytology is reported as Bethesda category V (suspicious for malignancy). Which is the most appropriate next step?

  1. Observation with annual ultrasound
  2. Radioiodine ablation without surgery
  3. Repeat fine-needle aspiration in 12 months
  4. Referral for diagnostic hemithyroidectomy or thyroidectomy Correct answer.

Explanation

Bethesda category V carries a substantial risk of malignancy and warrants diagnostic surgery, usually hemithyroidectomy or total thyroidectomy, for definitive histology. Repeat cytology or observation would delay treatment of a likely cancer.

Question 14Medicine

A 72-year-old woman has a 3-day history of a painful red eye with reduced visual acuity and a hazy cornea. She has a history of angle-closure glaucoma. Which is the most appropriate immediate management?

  1. Warm compresses and analgesia
  2. Urgent ophthalmology referral for topical and systemic pressure-lowering therapy Correct answer.
  3. Dilating eye drops
  4. Topical antibiotic drops and outpatient review

Explanation

Acute angle-closure glaucoma is an ophthalmological emergency requiring urgent pressure-lowering therapy and definitive treatment such as laser peripheral iridotomy. Delay risks permanent optic nerve damage.

Question 15Medicine

A 6-week-old infant is brought in with projectile non-bilious vomiting after feeds and failure to thrive. A firm olive-shaped mass is palpable in the right upper quadrant. Which is the most likely diagnosis?

  1. Hypertrophic pyloric stenosis Correct answer.
  2. Duodenal atresia
  3. Intussusception
  4. Gastro-oesophageal reflux

Explanation

Projectile non-bilious vomiting in a 6-week-old with an olive-shaped mass and hypochloraemic hypokalaemic metabolic alkalosis is classic for hypertrophic pyloric stenosis. Ultrasound of the pylorus confirms the diagnosis.

Question 16Medicine

A 60-year-old man has an eGFR of 28 mL/min/1.73m², a urine albumin-to-creatinine ratio of 45 mg/mmol and type 2 diabetes. Which medication class slows progression of his diabetic kidney disease?

  1. ACE inhibitor or ARB Correct answer.
  2. Alpha-blocker
  3. Thiazolidinedione
  4. Loop diuretic

Explanation

ACE inhibitors or ARBs reduce intraglomerular pressure and slow progression of albuminuric diabetic kidney disease, with monitoring of potassium and creatinine after initiation. They are indicated for albuminuria regardless of blood pressure.

Question 17Medicine

A 25-year-old man returns from a trip to sub-Saharan Africa with cyclical fevers, rigors and a palpable spleen. A blood film shows ring-form trophozoites within erythrocytes. Which is the most appropriate initial treatment for uncomplicated falciparum malaria?

  1. Artemisinin-based combination therapy Correct answer.
  2. Chloroquine alone
  3. Doxycycline alone
  4. Primaquine alone

Explanation

Artemisinin-based combination therapy is the recommended first-line treatment for uncomplicated Plasmodium falciparum malaria because of widespread chloroquine resistance. Primaquine is used for hypnozoite eradication in vivax and ovale malaria.

Question 18Medicine

A 70-year-old man has a 6-month history of progressive exertional breathlessness and ankle swelling. Echocardiography shows a left ventricular ejection fraction of 30%. He is on an ACE inhibitor and beta-blocker. Which additional agent reduces mortality in heart failure with reduced ejection fraction?

  1. Verapamil
  2. Frusemide
  3. Digoxin
  4. Mineralocorticoid receptor antagonist Correct answer.

Explanation

Mineralocorticoid receptor antagonists such as spironolactone reduce mortality in heart failure with reduced ejection fraction and are added to ACE inhibitors and beta-blockers. Diuretics relieve symptoms but have not been shown to improve survival.

Question 19Medicine

A 30-year-old woman has a 2-day history of right lower quadrant pain with fever and localised peritonism. A pregnancy test is negative and ultrasound suggests appendicitis. Which is the most appropriate management?

  1. Intravenous antibiotics alone with outpatient review
  2. Laparoscopic appendicectomy Correct answer.
  3. Discharge with analgesia and reassessment in 48 hours
  4. Urgent colonoscopy

Explanation

Acute appendicitis with peritonism is treated definitively with appendicectomy, preferably laparoscopically. Antibiotic-only management may be considered in selected uncomplicated cases but is not standard for peritonitic disease.

Question 20Medicine

A 65-year-old man with chronic obstructive pulmonary disease has an oxygen saturation of 86% on air and is drowsy. Which is the most appropriate initial oxygen therapy?

  1. Heliox without oxygen
  2. No oxygen therapy
  3. High-flow oxygen to a target saturation of 100%
  4. Controlled oxygen to a target saturation of 88-92% Correct answer.

Explanation

In COPD with a history of hypercapnia, oxygen should be titrated to a target saturation of 88-92% to avoid worsening hypercapnia and respiratory acidosis. Hypoxaemia must still be corrected, but over-oxygenation is avoided.

Question 21Medicine

A 40-year-old woman presents with a generalised seizure and is found to have a blood glucose of 1.8 mmol/L. Which is the most appropriate immediate treatment?

  1. Intravenous phenytoin
  2. Intravenous insulin with glucose
  3. Intravenous 10% glucose or 50% glucose with thiamine if malnourished Correct answer.
  4. Oral glucose gel

Explanation

Severe hypoglycaemia with neurological compromise is treated with intravenous glucose, with thiamine given concurrently if there is a risk of deficiency. Oral glucose is unsafe in a patient who is having seizures or is unconscious.

Question 22Medicine

A 55-year-old woman has a serum calcium of 3.1 mmol/L with a raised parathyroid hormone and a low phosphate. Which is the most likely diagnosis?

  1. Vitamin D deficiency
  2. Primary hyperparathyroidism Correct answer.
  3. Multiple myeloma
  4. Hypoparathyroidism

Explanation

Hypercalcaemia with inappropriately elevated parathyroid hormone and hypophosphataemia is characteristic of primary hyperparathyroidism, most often due to a parathyroid adenoma. Vitamin D deficiency causes hypocalcaemia, not hypercalcaemia.

Question 23Medicine

A 50-year-old man has a 3-month history of fatigue, weight loss and a haemoglobin of 78 g/L with a mean corpuscular volume of 72 fL. He reports black stools. Which is the most appropriate investigation to identify the source of his anaemia?

  1. Bone marrow aspiration
  2. Reticulocyte count alone
  3. Upper and lower gastrointestinal endoscopy Correct answer.
  4. Serum vitamin B12 assay

Explanation

Microcytic anaemia with a history of melaena suggests iron deficiency from gastrointestinal blood loss, and bidirectional endoscopy identifies the source. Iron studies should be checked but endoscopy is the key diagnostic step.

Question 24Medicine

A 28-year-old woman has a 2-day history of pleuritic chest pain, fever and a pleural rub, with a chest radiograph showing a small pleural effusion. Thoracentesis reveals a pH of 7.10 and glucose of 1.5 mmol/L. Which is the most appropriate management?

  1. Insertion of a chest drain Correct answer.
  2. Oral antibiotics alone without drainage
  3. Thoracoscopy with talc pleurodesis
  4. Observation with repeat radiograph in 48 hours

Explanation

A pleural fluid pH below 7.20 or glucose below 2.2 mmol/L in parapneumonic effusion indicates complicated effusion requiring chest drain insertion. Antibiotics alone are insufficient once the fluid is loculated or purulent.

Question 25Medicine

A 70-year-old woman is admitted with confusion and a urinary tract infection. She is on warfarin and her INR is 6.5 with no bleeding. Which is the most appropriate management?

  1. Give fresh frozen plasma immediately
  2. Give intravenous heparin
  3. Continue warfarin at the same dose
  4. Withhold warfarin and give oral vitamin K Correct answer.

Explanation

A markedly elevated INR without bleeding is managed by withholding warfarin and giving oral vitamin K, with prothrombin complex concentrate reserved for major bleeding. Fresh frozen plasma is not indicated in the absence of haemorrhage.

Question 26Medicine

A 58-year-old man is admitted with a 2-day history of fever, productive cough and right-sided pleuritic chest pain. Observations: temperature 38.9°C, respiratory rate 26/min, blood pressure 95/60 mmHg, heart rate 108/min. Chest radiograph shows right lower lobe consolidation. Using the CURB-65 score, which single feature in this presentation contributes one point?

  1. Temperature of 38.9°C
  2. Respiratory rate of 26/min Correct answer.
  3. Heart rate of 108/min
  4. Right lower lobe consolidation on radiograph

Explanation

CURB-65 scores one point each for Confusion, Urea above 7 mmol/L, Respiratory rate 30/min or more, Blood pressure (systolic below 90 mmHg or diastolic 60 mmHg or less) and age 65 or over. A respiratory rate of 26/min does not reach the 30/min threshold, so it scores nothing; temperature, heart rate and radiographic consolidation are not components of the score at all.

Question 27Medicine

A 24-year-old man is brought to the emergency department after a high-speed motor vehicle collision. He is confused, his systolic blood pressure is 82 mmHg and heart rate 130/min. He has distended neck veins, tracheal deviation to the left and absent breath sounds over the right hemithorax with hyper-resonance to percussion. What is the most appropriate immediate step?

  1. Urgent needle decompression of the right hemithorax Correct answer.
  2. Intravenous fluid resuscitation and observation
  3. Immediate chest drain insertion after imaging
  4. Urgent chest radiograph before any intervention

Explanation

This is tension pneumothorax, a clinical diagnosis in an unstable patient: hypotension, distended neck veins, tracheal deviation away from the affected side and hyper-resonance with absent breath sounds. Needle decompression must precede imaging because delaying for a radiograph can be fatal. A chest drain follows decompression, but it is not the first step and should not wait for imaging.

Question 28Medicine

A 68-year-old woman presents with sudden painless loss of vision in the right eye that lasted about 20 minutes and has now fully resolved. She has a history of hypertension and smokes. Which underlying diagnosis should be actively sought?

  1. Acute angle-closure glaucoma
  2. Giant cell arteritis
  3. Retinal detachment
  4. Carotid artery stenosis Correct answer.

Explanation

Transient monocular visual loss (amaurosis fugax) that resolves within minutes is a classic feature of retinal ischaemia from emboli, most often arising from ipsilateral carotid atherosclerotic disease or cardiac sources. It is a warning of impending stroke and requires urgent assessment of the carotids and cardiovascular risk. Painless transient loss is not typical of angle-closure glaucoma, detachment or giant cell arteritis.

Question 29Medicine

A 45-year-old woman has a 6-month history of fatigue, weight gain, cold intolerance and constipation. Examination shows dry skin, bradycardia and delayed relaxation of the ankle reflexes. Which single test best confirms the diagnosis?

  1. Thyroid-stimulating hormone Correct answer.
  2. Serum cortisol
  3. Serum free T4 alone
  4. Thyroid peroxidase antibody

Explanation

Primary hypothyroidism is best confirmed with thyroid-stimulating hormone, which is elevated when the thyroid gland is failing. Free T4 is usually measured alongside to grade severity but a normal or low free T4 alone does not confirm primary thyroid failure. Antibodies and cortisol address different questions.

Question 30Medicine

A 30-year-old woman at 34 weeks' gestation presents with a 2-hour history of painless bright red vaginal bleeding. Her uterus is soft and non-tender, the fetal heart rate is normal and the presentation is cephalic. What is the most likely diagnosis?

  1. Placental abruption
  2. Placenta praevia Correct answer.
  3. Cervical ectropion
  4. Uterine rupture

Explanation

Painless, bright red vaginal bleeding in late pregnancy with a soft, non-tender uterus is characteristic of placenta praevia. Placental abruption typically produces painful bleeding with a tense, tender uterus and fetal compromise. Digital vaginal examination should be avoided until praevia is excluded by ultrasound.

Question 31Medicine

A 72-year-old man has a 3-month history of progressive exertional breathlessness. Examination reveals a raised jugular venous pressure, bilateral basal crackles and pitting oedema to the mid-shins. Which single finding on echocardiography would most strongly support a diagnosis of heart failure with reduced ejection fraction?

  1. Left ventricular hypertrophy with normal ejection fraction
  2. Left ventricular ejection fraction of 30% Correct answer.
  3. Moderate mitral regurgitation
  4. Dilated left atrium with normal ejection fraction

Explanation

Heart failure with reduced ejection fraction is defined by a left ventricular ejection fraction of 40% or less in the presence of symptoms and signs of heart failure. Hypertrophy, atrial dilatation and mitral regurgitation may accompany heart failure but do not define the reduced-ejection-fraction phenotype.

Question 32Medicine

A 26-year-old woman has a 3-day history of dysuria, urinary frequency and suprapubic discomfort. She is otherwise well, afebrile, not pregnant and has no vaginal discharge. Which is the most appropriate initial management?

  1. A short course of oral trimethoprim Correct answer.
  2. Immediate referral for intravenous antibiotics
  3. Reassurance without antibiotics
  4. Urine culture and await results before treating

Explanation

Uncomplicated cystitis in a non-pregnant woman is treated empirically with a short course of an appropriate oral antibiotic such as trimethoprim, nitrofurantoin or fosfomycin. Urine culture is reserved for complicated, recurrent or treatment-failure cases. Empirical treatment avoids delay and is supported by guidelines.

Question 33Medicine

A 64-year-old man with type 2 diabetes has a serum creatinine of 210 µmol/L, an eGFR of 28 mL/min/1.73m² and a potassium of 5.9 mmol/L. He is on ramipril, metformin and ibuprofen for knee pain. Which single medication change is most appropriate?

  1. Add a potassium binder while continuing all drugs
  2. Stop ibuprofen Correct answer.
  3. Continue metformin unchanged
  4. Increase ramipril

Explanation

Non-steroidal anti-inflammatory drugs reduce renal perfusion and worsen kidney function and hyperkalaemia, especially with an ACE inhibitor and chronic kidney disease. Stopping ibuprofen addresses a reversible contributor. Metformin should be reviewed at this eGFR and ramipril should not be increased with hyperkalaemia.

Question 34Medicine

A 35-year-old man presents with a 4-week history of productive cough, night sweats, weight loss and low-grade fever. Sputum is sent for acid-fast bacilli. Which single finding would most strongly support active pulmonary tuberculosis?

  1. Positive interferon-gamma release assay
  2. Upper lobe scarring on chest radiograph
  3. Non-caseating granulomas on biopsy
  4. Caseating granulomas with acid-fast bacilli on sputum Correct answer.

Explanation

Demonstration of acid-fast bacilli with caseating granulomatous inflammation provides microbiological and histological confirmation of active tuberculosis. Interferon-gamma release assays indicate infection (latent or active) but cannot distinguish active disease, and non-caseating granulomas are non-specific.

Question 35Medicine

A 22-year-old woman presents with a 2-week history of palpitations, heat intolerance, tremor and weight loss. She has a smooth diffuse goitre and a fine tremor. TSH is suppressed and free T4 is elevated. Which single feature would most specifically suggest Graves' disease rather than a toxic multinodular goitre?

  1. Elevated free T4
  2. Diffuse goitre with eye signs Correct answer.
  3. Suppressed TSH
  4. Tachycardia

Explanation

Graves' disease is an autoimmune condition causing a diffuse goitre and extrathyroidal features such as ophthalmopathy and pretibial myxoedema. Suppressed TSH, elevated free T4 and tachycardia occur in thyrotoxicosis of any cause and do not distinguish the aetiology.

Question 36Medicine

A 3-year-old child is brought in with a 2-day history of fever, sore throat and drooling, and is sitting forward refusing to lie down. The voice is muffled. Which is the most appropriate immediate action?

  1. Give oral antibiotics and discharge
  2. Send for a lateral neck radiograph before assessment
  3. Inspect the throat with a tongue depressor
  4. Urgent senior airway assessment with anaesthetic support Correct answer.

Explanation

Drooling, tripod positioning, muffled voice and fever in a young child suggest acute epiglottitis with impending airway obstruction. The priority is to keep the child calm and involve senior anaesthetic and ENT teams for controlled airway management. Throat inspection or forcing the child to lie down can precipitate complete obstruction.

Question 37Medicine

A 55-year-old man has sudden onset of severe generalised headache, vomiting and neck stiffness. He is alert but photophobic. CT head is normal. Which single next step is most appropriate?

  1. Lumbar puncture for xanthochromia Correct answer.
  2. Discharge with analgesia
  3. Immediate thrombolysis
  4. MRI brain in 6 weeks

Explanation

Sudden severe headache with meningism raises subarachnoid haemorrhage, and a normal CT within hours does not exclude it. Lumbar puncture for xanthochromia is the next step to detect bilirubin from red cell breakdown. Thrombolysis is for acute ischaemic stroke and is contraindicated here.

Question 38Medicine

A 70-year-old woman has a 2-week history of a painful blistering rash in a dermatomal distribution on the left chest. She also reports a burning sensation before the rash appeared. Which is the most likely diagnosis?

  1. Cellulitis
  2. Herpes zoster Correct answer.
  3. Contact dermatitis
  4. Herpes simplex

Explanation

A painful, unilateral, dermatomal vesicular rash preceded by burning or tingling is characteristic of herpes zoster, caused by reactivation of varicella-zoster virus in a sensory ganglion. The prodromal pain and dermatomal distribution distinguish it from other causes.

Question 39Medicine

A 48-year-old woman has a 3-month history of episodic vertigo lasting minutes, associated with unilateral hearing loss and tinnitus. Examination between episodes is normal. Which single diagnosis fits best?

  1. Ménière's disease Correct answer.
  2. Vertebrobasilar stroke
  3. Benign paroxysmal positional vertigo
  4. Vestibular schwannoma

Explanation

Ménière's disease is characterised by recurrent episodes of vertigo lasting minutes to hours, fluctuating sensorineural hearing loss, tinnitus and aural fullness. Benign paroxysmal positional vertigo causes brief positional vertigo without hearing loss, and a vestibular schwannoma causes progressive, not fluctuating, unilateral hearing loss.

Question 40Medicine

A 20-year-old man has a 5-day history of a single painful penile ulcer with a clean base and tender inguinal lymphadenopathy. He is otherwise well. Which is the most appropriate initial investigation?

  1. Dark-ground microscopy for Treponema pallidum
  2. Nucleic acid amplification test for herpes simplex virus Correct answer.
  3. Serology for HIV
  4. Urine culture

Explanation

A painful genital ulcer with a clean base and tender lymphadenopathy is typical of primary genital herpes, and nucleic acid amplification testing of the ulcer is the preferred diagnostic test. Dark-ground microscopy is for syphilis, which typically causes a painless ulcer with a hard base and non-tender nodes.

Question 41Surgery

A 24-year-old man presents 6 hours after blunt abdominal trauma with left upper quadrant pain and haemodynamic stability. CT shows a grade III splenic laceration with no active contrast extravasation. What is the most appropriate initial management?

  1. Immediate splenectomy
  2. Splenic artery embolisation in all grade III injuries
  3. Non-operative management with close monitoring in a facility able to intervene Correct answer.
  4. Diagnostic peritoneal lavage to decide on laparotomy

Explanation

Haemodynamically stable patients with blunt splenic injury and no active bleeding on CT are managed non-operatively with serial examination, haemoglobin monitoring and ready access to theatre or angiography. Splenectomy is reserved for haemodynamic instability or failure of non-operative management. Embolisation is considered for high-grade injuries or contrast blush, not routinely for every grade III injury.

Question 42Surgery

Which finding on abdominal examination is most suggestive of acute appendicitis?

  1. Rebound tenderness confined to the epigastrium
  2. Generalised guarding with board-like rigidity
  3. Cullen sign
  4. Pain on release of pressure in the right iliac fossa after deep palpation of the left iliac fossa Correct answer.

Explanation

Rovsing sign describes pain felt in the right iliac fossa when the left iliac fossa is palpated and released, reflecting peritoneal irritation adjacent to the inflamed appendix. Board-like rigidity suggests generalised peritonitis rather than early appendicitis. Cullen sign is periumbilical bruising associated with retroperitoneal haemorrhage such as pancreatitis.

Question 43Surgery

A 62-year-old woman has a 3 cm moderately differentiated rectal adenocarcinoma 7 cm from the anal verge with no distant metastases. Staging shows T3N1 disease. What is the standard initial treatment approach?

  1. Local excision with surveillance
  2. Immediate abdominoperineal resection
  3. Systemic chemotherapy alone with surgery reserved for progression
  4. Neoadjuvant chemoradiotherapy followed by total mesorectal excision Correct answer.

Explanation

Locally advanced rectal cancer (T3 or node-positive) is treated with neoadjuvant chemoradiotherapy or short-course radiotherapy before total mesorectal excision to reduce local recurrence. A tumour 7 cm from the verge is generally amenable to anterior resection with sphincter preservation. Local excision is only for early T1 lesions without nodal involvement.

Question 44Surgery

Which is the most common cause of acute pancreatitis in New Zealand?

  1. Endoscopic retrograde cholangiopancreatography
  2. Alcohol
  3. Hypertriglyceridaemia
  4. Gallstones Correct answer.

Explanation

Gallstones and alcohol are the two leading causes of acute pancreatitis, and gallstones are the most common overall in most Western populations including New Zealand. Hypertriglyceridaemia and post-ERCP pancreatitis are recognised but less frequent causes. Identifying gallstones matters because cholecystectomy prevents recurrence.

Question 45Surgery

A 70-year-old man presents with a pulsatile abdominal mass. CT shows an infrarenal abdominal aortic aneurysm of 5.0 cm in maximum diameter. He is asymptomatic. What is the most appropriate management?

  1. Lifestyle advice alone with no further imaging
  2. Vascular follow-up with ultrasound surveillance every 3 to 6 months Correct answer.
  3. Immediate emergency open repair
  4. Ultrasound surveillance every 12 months

Explanation

Elective repair is generally offered to men with infrarenal aortic aneurysms of 5.5 cm or more, or with rapid expansion or symptoms. An asymptomatic 5.0 cm aneurysm without other high-risk features warrants vascular follow-up and ultrasound surveillance every 3 to 6 months rather than immediate surgery.

Question 46Surgery

Which of the following is the most reliable clinical sign of acute compartment syndrome in the lower leg after tibial fracture?

  1. Paralysis of the limb
  2. Pallor of the foot
  3. Pain on passive stretch of the toes disproportionate to the injury Correct answer.
  4. Absent dorsalis pedis pulse

Explanation

Pain out of proportion and pain on passive stretch are the earliest and most reliable signs of compartment syndrome. Pulselessness, pallor and paralysis are late signs and their absence does not exclude the diagnosis. Urgent fasciotomy is required once the diagnosis is made.

Question 47Surgery

A 45-year-old woman has a 2 cm thyroid nodule. Fine needle aspiration cytology is reported as Bethesda category IV (suspicious for follicular neoplasm). What is the most appropriate next step?

  1. Repeat fine needle aspiration in 6 weeks
  2. Radioactive iodine ablation
  3. Observation with ultrasound in 12 months
  4. Diagnostic hemithyroidectomy for histological assessment Correct answer.

Explanation

Bethesda IV cytology cannot distinguish follicular adenoma from follicular carcinoma because that distinction requires evidence of capsular or vascular invasion on histology. Diagnostic hemithyroidectomy provides the necessary tissue. Repeat cytology and observation would delay diagnosis of a possible malignancy.

Question 48Surgery

A 30-year-old man sustains a stab wound to the right chest. He is hypotensive with distended neck veins and absent breath sounds on the right. What is the most immediate intervention?

  1. Urgent chest X-ray
  2. Needle decompression of the right pleural space Correct answer.
  3. Pericardiocentesis
  4. Emergency thoracotomy

Explanation

The triad of hypotension, distended neck veins and absent breath sounds after chest trauma suggests tension pneumothorax, which is a clinical diagnosis requiring immediate needle decompression before imaging. Chest X-ray would delay life-saving treatment. Pericardiocentesis is for suspected cardiac tamponade.

Question 49Surgery

Which factor most strongly predicts the need for surgery in a patient with adhesive small bowel obstruction?

  1. A history of previous abdominal surgery
  2. Absence of flatus for 12 hours
  3. Failure to resolve with conservative management over 24 to 48 hours Correct answer.
  4. Vomiting at presentation

Explanation

Most adhesive small bowel obstructions resolve with nasogastric decompression and intravenous fluids. Failure to improve within 24 to 48 hours, or signs of strangulation such as peritonitis, fever or rising lactate, prompts operative intervention. A previous laparotomy is the usual cause but does not by itself predict the need for surgery.

Question 50Surgery

A 55-year-old man has painless visible haematuria. What is the most appropriate initial investigation strategy?

  1. Cystoscopy and upper tract imaging Correct answer.
  2. Urine culture alone
  3. Renal ultrasound alone
  4. Repeat urinalysis in 3 months

Explanation

Painless visible haematuria in an adult requires investigation for urothelial malignancy with cystoscopy and imaging of the upper tracts, usually CT urography. Urine culture and repeat urinalysis do not exclude cancer. Ultrasound alone may miss small urothelial lesions.