PLAB 1 Clinical Medicine 1 — Questions and Answers
Question 1: A 65-year-old man presents with crushing central chest pain radiating to the left arm, sweating, and nausea for 2 hours. ECG shows ST elevation in leads II, III, and aVF. What is the most likely diagnosis?
- Anterior STEMI
- Inferior STEMI (Correct answer)
- Unstable angina
- Pericarditis
Correct answer: Inferior STEMI
ST elevation in leads II, III, and aVF indicates inferior STEMI, reflecting occlusion of the right coronary artery (RCA) in most patients. The clinical picture — crushing central chest pain with radiation, diaphoresis and nausea — is classic for acute MI.
Question 2: A 70-year-old woman presents with sudden onset severe headache described as 'the worst of her life', nausea and vomiting, and neck stiffness. CT head is normal. What is the most important next investigation?
- MRI brain
- Lumbar puncture (Correct answer)
- EEG
- Carotid Doppler
Correct answer: Lumbar puncture
This presentation is classic for subarachnoid haemorrhage (SAH). When CT head is negative (sensitivity ~98% within 6 hours but lower thereafter), lumbar puncture is essential to look for xanthochromia (yellow discolouration of CSF) due to haemoglobin breakdown, confirming SAH.
Question 3: A 45-year-old woman with known rheumatoid arthritis on methotrexate presents with a 2-week history of dry cough and progressive breathlessness. CXR shows bilateral interstitial shadowing. What is the most likely diagnosis?
- Community-acquired pneumonia
- Methotrexate-induced pneumonitis (Correct answer)
- Pulmonary embolism
- Cardiac failure
Correct answer: Methotrexate-induced pneumonitis
Methotrexate pneumonitis is a well-recognised and potentially serious complication of methotrexate therapy. It presents with dry cough, progressive dyspnoea, and bilateral interstitial shadowing on CXR. Methotrexate should be stopped immediately and the patient referred urgently.
Question 4: A 25-year-old woman presents with a 3-month history of fatigue, weight loss, mouth ulcers, and a butterfly-shaped facial rash worsened by sunlight. Blood tests show positive ANA and anti-dsDNA antibodies, lymphopenia, and proteinuria. What is the most likely diagnosis?
- Systemic sclerosis
- Systemic lupus erythematosus (SLE) (Correct answer)
- Dermatomyositis
- Sjögren's syndrome
Correct answer: Systemic lupus erythematosus (SLE)
This is a classic presentation of SLE: the malar (butterfly) rash, photosensitivity, oral ulcers, positive ANA and anti-dsDNA (highly specific for SLE), lymphopenia, and renal involvement (proteinuria). Anti-dsDNA antibodies are highly specific for SLE.
Question 5: A 60-year-old man with a history of alcohol excess presents with haematemesis. On examination he has spider naevi, palmar erythema, and ascites. OGD shows oesophageal varices with active bleeding. What is the most appropriate initial management?
- Urgent surgical ligation of varices
- Terlipressin IV plus urgent endoscopic band ligation (Correct answer)
- IV omeprazole infusion
- Oral propranolol
Correct answer: Terlipressin IV plus urgent endoscopic band ligation
Acute variceal bleeding is managed with: (1) terlipressin (vasopressin analogue that reduces portal pressure) started immediately; (2) prophylactic IV antibiotics (ciprofloxacin or tazobactam); (3) urgent endoscopic band ligation within 12 hours. Terlipressin reduces mortality when started before endoscopy.
Question 6: A 72-year-old man presents with sudden-onset unilateral weakness affecting the face, arm, and leg, slurred speech, and left homonymous hemianopia. Symptoms began 3 hours ago. CT head is normal. What is the most appropriate immediate management?
- IV alteplase (thrombolysis) after confirming no contraindications (Correct answer)
- Aspirin 300mg orally and urgent neurology referral
- Anticoagulation with heparin
- CT angiography only, then discharge
Correct answer: IV alteplase (thrombolysis) after confirming no contraindications
This is an acute ischaemic stroke presenting within 4.5 hours. With a normal CT head (excluding haemorrhage) and no contraindications, IV alteplase thrombolysis should be given. The time window is critical — 'time is brain'. NICE recommends thrombolysis within 4.5 hours of onset.
PLAB 1 Clinical Medicine 1
A 65-year-old man presents with crushing central chest pain radiating to the left arm, sweating, and nausea for 2 hours.
ECG shows ST elevation in leads II, III, and aVF.
What is the most likely diagnosis?