Infectious Disease Compendium

Cystoisosporia (Isospora) belli

Microbiology

A protozoa, it is found in tropical areas of the world. There are over 248 species with the poor; the house sparrow having 12 species. Found on stool exam. I prefer my stool exams to be open book. Shows up on a modified acid-fast stain.

Epidemiologic Risks

Eating food and water contaminated with human stool. And as I have probably mentioned elsewhere, most of the food you eat has a fine patina of human stool. Has been associated with basil pesto salads.

Syndromes

Diarrhea, especially in AIDS patients and other immuno-incompetent patients. It tends to be watery and not bloody. It can cause eosinophilia.

Treatment

TMP/Sulfa qid x 10 days.

Pyrimethamine 50 to 75 mg x 2 doses 12 or 24 hours apart.

Ciprofloxacin is a second-line alternative but not as good.

Notes

Last update: 05/05/18