Diarrhea Caused by a Coccidian Parasite, Cryptosporidium

Among the many agents that cause diarrhea are several animal parasites. Cryptosporidium, a minute protozoan, is a rarely diagnosed coccidium parasite that has been implicated in several human cases of diarrhea. A brief review of the Coccidia is presented. Discussion focuses on Cryptosporidium — its life cycle, pathogenesis, unique features, and laboratory diagnosis. Recent reported cases are reviewed, suggested methods for laboratory detection of the oocysts are presented, and morphologic descriptions of the parasite are included.