Key points
- Single-best-answer clinical vignettes in the style of final and licensing exams. Read the stem, choose one answer, then reveal the explanation.
- Topics: asthma, COPD, pneumonia, pulmonary embolism, pneumothorax, pleural effusion, tuberculosis, lung cancer, respiratory failure and interpretation of blood gases.
- Each explanation covers why the answer is right and why the distractors are wrong.
- Treatment details follow widely used international guidance. Check your local protocol before treating a patient.
Questions
1. A 24-year-old has wheeze and cough at night and after exercise. Peak flow varies by 25% over the day. What is the best first-line treatment for long-term control according to current international guidance?
A. Regular oral salbutamol
B. Inhaled corticosteroid with as-needed reliever
C. Oral theophylline
D. Long-acting beta-agonist alone
E. Oral antibiotics
Answer: B. Asthma is chronic airway inflammation, so an inhaled corticosteroid is the foundation of controller treatment, with a short-acting or combination reliever. A long-acting beta-agonist must never be used alone in asthma because it raises the risk of severe exacerbation and death. Antibiotics are not indicated without evidence of infection.
2. A man with asthma is brought in unable to complete sentences, with a pulse of 130, a peak flow of 30% of his best and a silent chest. What does the silent chest indicate?
A. Mild exacerbation
B. Very severe, life-threatening asthma
C. Pneumothorax only
D. He is improving
E. Anxiety
Answer: B. A silent chest, cyanosis, exhaustion, confusion or a peak flow below 33% of best are life-threatening features, because airflow is too low to produce wheeze. Give high-flow oxygen, nebulised salbutamol with ipratropium, systemic corticosteroids, and consider intravenous magnesium. A normal or rising carbon dioxide level in an asthmatic who is tiring is ominous.
3. A 65-year-old long-term smoker has a daily productive cough, breathlessness, an FEV1/FVC ratio of 0.62 after bronchodilator and an FEV1 of 55% predicted. Which intervention reduces mortality?
A. Inhaled long-acting bronchodilator
B. Smoking cessation
C. Oral mucolytic
D. Routine long-term oral steroids
E. Chest physiotherapy
Answer: B. Smoking cessation slows the decline in lung function and is the main intervention that alters the course of COPD. Long-term oxygen therapy for chronic hypoxaemia also improves survival. Bronchodilators relieve symptoms and reduce exacerbations. Long-term oral steroids cause harm without benefit.
4. A patient with an exacerbation of COPD is hypoxic and drowsy. Which oxygen strategy is correct?
A. Give 100% oxygen to normalise saturation
B. Controlled oxygen targeting a saturation of 88 to 92%
C. Avoid oxygen completely
D. Give oxygen only by nasal cannula at 15 L/min
E. Oxygen is not needed if breathless
Answer: B. In patients at risk of carbon dioxide retention, target 88 to 92% with a controlled-flow mask, and check arterial blood gases. Too much oxygen can worsen hypercapnia. Withholding oxygen from a hypoxic patient is also dangerous. Non-invasive ventilation is used when respiratory acidosis persists.
5. A 70-year-old has fever, cough with rust-coloured sputum, a respiratory rate of 32, confusion and blood pressure of 90/60 mmHg. Which tool helps decide severity and where to treat?
A. Glasgow Coma Scale alone
B. CURB-65
C. Wells score
D. MELD score
E. APGAR score
Answer: B. CURB-65 scores confusion, urea above 7 mmol/L, respiratory rate 30 or more, blood pressure below 90 systolic or 60 diastolic, and age 65 or over. A score of 3 or more indicates severe pneumonia and hospital or intensive care. The Wells score is for pulmonary embolism and deep vein thrombosis.
6. Which organism is the most common cause of community-acquired pneumonia in adults?
A. Pseudomonas aeruginosa
B. Streptococcus pneumoniae
C. Klebsiella pneumoniae
D. Pneumocystis jirovecii
E. Legionella pneumophila
Answer: B. Streptococcus pneumoniae is the most common cause, which is why first-line oral therapy such as amoxicillin covers it. Pseudomonas and Klebsiella are more typical in hospital-acquired infection and alcohol-related disease. Pneumocystis causes pneumonia in the immunosuppressed, including people with advanced HIV.
7. A 35-year-old woman on the oral contraceptive pill flies back from a long journey and has sudden pleuritic chest pain and breathlessness. Oxygen saturation is 92% and the chest X-ray is clear. What is the most appropriate imaging test?
A. Exercise tolerance test
B. CT pulmonary angiography
C. Bronchoscopy
D. Spirometry
E. Lateral neck X-ray
Answer: B. Suspected pulmonary embolism is investigated with CT pulmonary angiography after a clinical probability score (for example Wells). A normal chest X-ray with hypoxia and pleuritic pain is the classic setting. A low-probability patient may have a D-dimer first. Start anticoagulation early if the delay would be long.
8. A tall, thin 19-year-old has sudden right-sided chest pain and breathlessness. There is hyper-resonance and absent breath sounds on the right. He is in severe distress with a deviated trachea and low blood pressure. What is the immediate management?
A. Chest X-ray, then decide
B. Immediate needle decompression
C. Intravenous antibiotics
D. Pleural aspiration after CT
E. Observation
Answer: B. Tracheal deviation with haemodynamic compromise indicates tension pneumothorax, which is a clinical diagnosis that needs immediate decompression, then a chest drain. Do not wait for imaging. A simple primary pneumothorax in a stable patient may be observed or aspirated.
9. A pleural fluid sample has protein of 40 g/L, LDH above two-thirds of the upper limit of normal serum LDH and a pleural-to-serum protein ratio of 0.7. How is the effusion classified, and what is a likely cause?
A. Transudate; heart failure
B. Exudate; pneumonia or malignancy
C. Transudate; cirrhosis
D. Exudate; nephrotic syndrome
E. Transudate; hypothyroidism only
Answer: B. Light's criteria define an exudate when the pleural-to-serum protein ratio is above 0.5, the LDH ratio is above 0.6, or the pleural LDH is above two-thirds of the upper serum limit. Common causes are infection, cancer and pulmonary embolism. Heart failure, cirrhosis and nephrotic syndrome produce transudates.
10. A 30-year-old man with HIV has a three-week cough, night sweats, weight loss and haemoptysis. Sputum is smear positive. What is the standard initial treatment regimen for drug-sensitive tuberculosis?
A. Isoniazid alone for 6 months
B. Rifampicin, isoniazid, pyrazinamide and ethambutol for 2 months, then rifampicin and isoniazid for 4 months
C. Rifampicin alone for 12 months
D. Streptomycin alone
E. Amoxicillin for 10 days
Answer: B. The standard regimen is a 2-month intensive phase of four drugs followed by a 4-month continuation phase of rifampicin and isoniazid. Isoniazid causes peripheral neuropathy, so pyridoxine is given. Patients on this regimen need monitoring of liver function. People living with HIV should start antiretroviral therapy within the first weeks of tuberculosis treatment.
11. A 62-year-old smoker has haemoptysis, hyponatraemia with concentrated urine and a central lung mass. What is the most likely tumour type?
A. Adenocarcinoma
B. Small-cell lung cancer
C. Squamous cell carcinoma with hypercalcaemia
D. Carcinoid
E. Hamartoma
Answer: B. Central masses with the syndrome of inappropriate antidiuretic hormone secretion point to small-cell lung cancer, a neuroendocrine tumour linked to smoking that spreads early. Squamous cell carcinoma is also central but causes hypercalcaemia through parathyroid hormone-related peptide. Adenocarcinoma is usually peripheral.
12. Arterial blood gas: pH 7.28, PaCO2 8.5 kPa (64 mmHg), bicarbonate 32 mmol/L. How is this best described?
A. Acute respiratory alkalosis
B. Chronic respiratory acidosis with an acute-on-chronic component
C. Metabolic acidosis
D. Metabolic alkalosis with respiratory compensation
E. Normal
Answer: B. A low pH with a high carbon dioxide indicates respiratory acidosis. A raised bicarbonate shows renal compensation over days, so the problem is long-standing, and the low pH shows an acute worsening on top. This is typical of a COPD exacerbation.
13. A 68-year-old retired clerk has progressive breathlessness, dry cough, finger clubbing and fine bibasal end-inspiratory crackles. Lung function shows a restrictive pattern. What is the most likely diagnosis?
A. Asthma
B. Idiopathic pulmonary fibrosis
C. Chronic bronchitis
D. Pneumothorax
E. Bronchiectasis with an obstructive pattern
Answer: B. Clubbing, bibasal "velcro" crackles and a restrictive pattern with reduced gas transfer suggest pulmonary fibrosis. The finding on CT of a usual interstitial pneumonia pattern clarifies the diagnosis. A history of bird or mould exposure would raise hypersensitivity pneumonitis, which should be excluded.
14. A patient on long-term amiodarone develops breathlessness and a dry cough. Which respiratory complication is this drug known for?
A. Pulmonary fibrosis
B. Pulmonary oedema only
C. Bronchospasm in all patients
D. Pleural mesothelioma
E. Sarcoidosis
Answer: A. Amiodarone can cause interstitial pneumonitis and pulmonary fibrosis, so patients need baseline and follow-up chest imaging and lung function. Other drugs linked to fibrosis include methotrexate, nitrofurantoin and bleomycin. Beta-blockers, rather than amiodarone, are the usual drug cause of bronchospasm.
15. A 45-year-old has a persistent cough and finger clubbing, with large volumes of purulent sputum and a history of childhood whooping cough. CT shows dilated airways with thickened walls. What is the diagnosis?
A. Bronchiectasis
B. Asthma
C. Lung abscess
D. Pulmonary embolism
E. Pleural effusion
Answer: A. Chronic productive cough with copious sputum, clubbing and the signet-ring sign on high-resolution CT define bronchiectasis. Causes include previous infection, cystic fibrosis and immune deficiency. Management is airway clearance with physiotherapy, antibiotics for exacerbations and treating the cause.
References
- Global Initiative for Asthma (GINA) report.
- Global Initiative for Chronic Obstructive Lung Disease (GOLD) report.
- British Thoracic Society guidelines on pneumonia, pneumothorax and pleural disease.
- World Health Organization. Consolidated guidelines on tuberculosis treatment.
- Kumar and Clark's Clinical Medicine. Elsevier.