Detection of Septata intestinalis in Stool Specimens and Coprodiagnostic Monitoring of Successful Treatment with Albendazole

We describe two patients with AIDS and chronic diarrhea in whom the microsporidian Septata intestinalis was detected with use of light and electron microscopic coprodiagnostic techniques. The ultrastructure of the microsporidian spores found in their stool specimens was distinctly different from that of Enterocytozoon bielensi, another intestinal microsporidian found in patients infected with human immunodeficiency virus. Electron microscopic examination of duodenal biopsy specimens available from one of the patients enabled identification of S. intestinalis and confirmed the similarity of spores found in feces and in duodenal tissue. Both patients' diarrhea stopped when they were treated with albendazole