Mycology/Parasitology USMLE Step 1 Practice Question
A 41-year-old man with a history of tuberculosis presents with cough and hemoptysis. Sputum smear shows acid-fast bacilli. He also has watery diarrhea and thrush. CD4 count is 85/μL. Stool sample reveals oval cysts with a partial wall, and intestinal biopsy shows the organism within enterocytes. Which of the following organisms is responsible for his diarrhea?
Answer choices
- ACryptosporidium parvumCorrect answer
- BEntamoeba histolytica
- CIsospora belli
- DGiardia lamblia
- ECandida albicans
- FCyclospora cayetanensis
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