Serious & Notifiable Infections — MCQs

A 23-year-old man completes 6 months of treatment for drug-sensitive pulmonary TB. His treatment included rifampicin, isoniazid, pyrazinamide, and ethambutol for 2 months, followed by rifampicin and isoniazid for 4 months. He was fully adherent. At treatment completion, he is asymptomatic. His chest X-ray shows residual fibrotic changes but no active disease. Sputum smears are negative. What is the most appropriate management?

A 44-year-old woman with a history of pulmonary tuberculosis treated 8 years ago presents with progressive dyspnoea on exertion. Examination reveals reduced breath sounds and stony dullness to percussion in the right lower zone. Chest X-ray shows a large right-sided pleural effusion. Pleural fluid analysis reveals: protein 45 g/L, LDH 890 U/L, glucose 1.8 mmol/L, pH 7.28, lymphocyte predominance. Pleural fluid culture is negative at 72 hours. What is the most appropriate next investigation?

A 7-year-old boy presents with fever, headache, and neck stiffness. LP shows: white cell count 3,200/mm³ (95% neutrophils), protein 3.5 g/L, glucose 1.5 mmol/L (plasma glucose 6.0 mmol/L). Gram stain shows Gram-negative diplococci. He is treated with IV ceftriaxone. Blood culture at 48 hours grows Neisseria meningitidis with MIC to penicillin of 0.25 mg/L. His clinical condition has improved. What is the most appropriate modification to antibiotic therapy?

A 50-year-old man with multidrug-resistant tuberculosis (resistant to rifampicin and isoniazid) is being treated with a second-line regimen including levofloxacin, bedaquiline, linezolid, cycloserine, and ethambutol. After 3 months of treatment, he develops progressive hearing loss and tinnitus. Audiometry confirms bilateral high-frequency sensorineural hearing loss. What is the most likely causative drug and appropriate management?

A 19-year-old university student is diagnosed with meningococcal meningitis confirmed by blood culture growing Neisseria meningitidis serogroup W. He shares a house with 5 other students. Public health authorities are contacted. Which of the following household contacts requires antibiotic prophylaxis?

A 65-year-old woman presents with a 3-day history of fever, confusion, and right-sided weakness. MRI brain shows multiple ring-enhancing lesions in the left frontal and parietal lobes with surrounding oedema. Lumbar puncture reveals: white cell count 180/mm³ (70% lymphocytes, 30% neutrophils), protein 2.1 g/L, glucose 2.5 mmol/L (plasma glucose 5.8 mmol/L). She immigrated from India 6 months ago. What is the most appropriate initial investigation to confirm the diagnosis?

A 34-year-old pregnant woman at 16 weeks gestation is identified as a contact of her brother who has smear-positive pulmonary tuberculosis. She is asymptomatic and her chest X-ray with abdominal shielding is normal. Her interferon-gamma release assay is positive. She has no history of previous TB treatment. What is the most appropriate management?

A 28-year-old man presents to the emergency department with sudden onset severe headache, fever of 39.2°C, and confusion. He has multiple small pustular lesions on his hands and face. Lumbar puncture shows: white cell count 2,400/mm³ (90% neutrophils), protein 2.8 g/L, glucose 1.8 mmol/L (plasma glucose 6.2 mmol/L). Gram stain shows Gram-positive cocci in clusters. He keeps pigeons as a hobby. What is the most appropriate empirical antibiotic therapy?

A 58-year-old man with chronic kidney disease (eGFR 35 mL/min/1.73m²) is diagnosed with drug-sensitive pulmonary tuberculosis. He is started on standard four-drug therapy. Three weeks into treatment, he develops painful paraesthesia in both feet and difficulty walking. Examination reveals reduced ankle reflexes and impaired vibration sense distally. What is the most likely cause and appropriate management?

A 22-year-old woman presents with a 12-hour history of severe headache, photophobia, and neck stiffness. Lumbar puncture reveals: opening pressure 28 cmH2O, CSF white cell count 850/mm³ (85% lymphocytes), protein 1.2 g/L, glucose 3.2 mmol/L (plasma glucose 5.8 mmol/L). Gram stain is negative. She had a similar episode 2 years ago that resolved spontaneously. What is the most likely diagnosis?