Inflammatory Bowel Disease USMLE Step 1 Practice Question
A 55-year-old man with a 3-month history of chronic diarrhea and 12-lb weight loss presents with migratory arthralgias and progressive confusion. Vital signs show BP 128/76, HR 92, RR 18, Temp 37.8°C, SpO2 98% on room air. Labs reveal hemoglobin 11.2 g/dL. Endoscopy with small-bowel biopsy demonstrates foamy macrophages in the lamina propria that stain positive with periodic acid-Schiff. Chest imaging shows no lymphadenopathy. Which organism is most likely responsible?
Answer choices
- AGiardia lamblia
- BTropheryma whippleiCorrect answer
- CVibrio cholerae
- DClostridioides difficile
- EYersinia enterocolitica
- FMycobacterium avium complex
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