Pneumonia USMLE Step 1 Practice Question
A 42-year-old woman with rheumatoid arthritis treated with methotrexate presents to the hospital with a 3-week history of productive cough, fever (38.5°C), and progressive dyspnea. She denies night sweats, hemoptysis, or recent travel. Vital signs include HR 102/min, BP 130/84 mmHg, RR 20/min, and SpO2 92% on room air. Physical examination reveals right upper lobe consolidation on percussion. Chest X-ray shows a solitary cavitary lesion in the right upper lobe. Laboratory studies reveal WBC 7,200/μL, hemoglobin 11.2 g/dL, and mild hyponatremia (Na+ 128 mEq/L). Tuberculin skin test shows 10 mm induration. Three sputum acid-fast bacillus (AFB) smears are negative. Blood cultures and sputum culture for routine bacteria are pending. Which of the following is the most appropriate next step in management?
Answer choices
- AObtain high-resolution CT chest and perform bronchoscopy with bronchoalveolar lavage for AFB culture and mycobacterial PCR
- BInitiate antituberculous therapy (isoniazid, rifampin, pyrazinamide, ethambutol) while awaiting sputum culture resultsCorrect answer
- CStart empiric broad-spectrum antibiotics (fluoroquinolone) and discontinue methotrexate; reassess in 1 week
- DPerform repeat tuberculin skin test with 2-step testing and defer treatment until conversion is documented
- EAdminister high-dose corticosteroids to reduce inflammation and obtain repeat chest X-ray in 48 hours
- FRefer for immediate lobectomy given cavitary lesion and immunosuppression
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