Mycology/Parasitology USMLE Step 1 Practice Question
A 42-year-old man with a 3-week history of cough presents for follow-up after a positive tuberculin skin test (induration 15 mm). He is currently asymptomatic with vital signs: BP 118/76, HR 78, RR 16, Temp 37.2°C, SpO2 98% on room air. Chest X-ray is clear without infiltrates. Sputum smear microscopy is negative on three consecutive samples. He denies fever, night sweats, or weight loss. Which intervention is most appropriate?
Answer choices
- ADischarge and monitor clinically without treatment
- BObtain sputum culture before any treatment
- CPerform repeat TST in 3 months
- DStart isoniazid monotherapy for latent TBCorrect answer
- EStart four-drug anti-TB therapy immediately
- FInitiate rifampin and pyrazinamide for 2 months followed by isoniazid monotherapy
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