[Antigen detection methods in diagnosis of amebiasis, giardiasis and cryptosporidiosis].

Amebiasis is a significant health problem in developing countries. Humans are infected by two morphologically identical species of Entamoeba. Entamoeba histolytica causes amebic colitis and liver abscess, and Entamoeba dispar is noninvasive. Giardia intestinalis infection is seen worldwide and in all age groups. But giardiasis is especially prevalent in countries with poor sanitation and unsafe water, where it's responsible for most cases of childhood diarrhea. Cryptosporidium parvum, a protozoon, is an obligate intracellular parasite which can cause fatal diarrheal disease in immunocompromised individuals. Generally, the diagnosis of human intestinal protozoa depends on microscopic detection. Microscopic detection is inexpensive, but it is very labor-intensive and requires a skilled microscopist. Antigen detection methods (direct fluorescent antibody, enzyme immunoassay, and rapid, dipstick-like tests) can be performed quickly and do not require an experienced and skilled microscopist. Recently, commercially available diagnostic kits for the intestinal parasites E. histolytica, G.intestinalis and Cryptosporidium spp. use the laboratory diagnosis. In this review, we aimed to discuss the diagnosis of these three intestinal parasites using the antigen tests.