Cryptosporidiosis among immunocompetent patients with gastroenteritis in Iran: a comparison with other enteropathogenic parasites.

BACKGROUND AND PURPOSE Cryptosporidium is a protozoan parasite that reproduces within the epithelial cells of several organs of vertebrate hosts. The manifestation of the disease is either self-limiting acute diarrhea in immunocompetent patients, or fatal chronic diarrhea in immunocompromised patients. Common clinical symptoms include watery diarrhea, abdominal pain, and weight loss. METHODS This randomized pilot study conducted in Tehran, Iran, included 104 children and adult patients with gastroenteritis referred to the Children's Hospital Centre and Pasteur Institute of Iran. Control samples from healthy individuals (36 children and adults) were also collected; the entire test group had diarrhea and the control group had formed stool consistency. Stool samples were primarily examined by the direct method, then fixed and tested by 3 assays including acid-fast staining, auramine phenol fluorescence, and direct fluorescence using monoclonal antibody. RESULTS The study revealed that 2.9% of the patients were infected by Cryptosporidium spp. Other parasites observed included Giardia lamblia (5.8%), Ascaris lumbricoides (1.9%), and Entamoeba histolytica (0.96%). Formed stool samples showed no oocysts of Cryptosporidia. CONCLUSIONS In addition to common enteropathogenic organisms, Cryptosporidium is indicated as a key causative agent of diarrhea in humans. Although cryptosporidiosis may, in many cases, be terminated by self-limiting mechanisms, it could cause pathologies requiring preventive and therapeutic policies.