Evaluation of new anti-infective drugs for the treatment of diarrhea caused by Cryptosporidium. Infectious Diseases Society of America and the Food and Drug Administration.

Cryptosporidium is a coccidian protozoan that produces symptoms by infesting the small bowel. The illness is characterized by watery stools, anorexia, weight loss, and abdominal pain. Diagnosis is made by visualization of the organisms on microscopic examination of stool. There currently is no approved therapy for this infection. A randomized, double-blind, placebo-controlled study design is recommended. Stratification of patients by age and immune status should be considered. Two stool samples obtained 48 hours to 7 days after completion of therapy should be negative for Cryptosporidium oocysts. Assessment of microbiological outcome is paramount.