Inflammatory Bowel Disease USMLE Step 1 Practice Question
A 34-year-old man with Crohn disease presents to the emergency department with a 3-week history of fever, productive cough, and progressive dyspnea. He has been on infliximab monotherapy for 8 months for refractory colonic disease. Vital signs include temperature 39.1°C, heart rate 108 bpm, respiratory rate 24/min, and oxygen saturation 89% on room air. Physical examination reveals diminished breath sounds at both lung bases. Chest X-ray shows bilateral hilar lymphadenopathy with mediastinal widening and right middle lobe infiltrate. Purified protein derivative (PPD) skin test is negative (5 mm induration). Sputum samples are sent for microscopy and culture. Which of the following is the most likely explanation for this patient's pulmonary presentation?
Answer choices
- ADisseminated histoplasmosis
- BAcute exacerbation of Crohn disease with pulmonary involvement
- CTuberculosis despite negative PPD skin testCorrect answer
- DDrug-induced systemic lupus erythematosus from TNF-α inhibitor
- EMycobacterium avium complex infection
- FSarcoidosis unrelated to Crohn disease
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