A case is described of a nonimmunocompromised man who presented with diarrh
ea, weight loss, and microcytic anemia. Colonoscopy revealed a pancolitis c
haracterized by aphthoid ulceration on endoscopy and intense tissue eosinop
hilic infiltrates on biopsy. Both colonic biopsies and stool aspirates reve
aled the larvae of Strongyloides stercoralis, thus confirming this parasite
as the causative agent for the colitis.