[Parasitic diarrhea in eutrophic and malnourished children]

Almost all children living in endemic zones are infected by gastrointestinal parasites. However only 3 to 5% develop diarrhea directly related to parasite infection. Entamoeba hystolytica and Entamoeba dispar coexist in many areas. In the past Entamoeba dispar was called non-pathogenic ameba. The vegetating forms are microscopically identical and detection of wall differences using biochemical tests is unreliable. Thus since it is rarely possible to determine whether or not a vegetating ameba found in stools is hematophagous treatment using metronidazole is the only alternative. Failure of such treatment indicates that dysentery is probably due to a cause other than amibiasis, e.g., bacterial infection in most cases. Another protozoan commonly found in endemic areas is Giardia. Giardia can cause diarrhea and this is frequently the case in undernourished children. Giardia infection leads to severe atrophic villosity requiring appropriate specific treatment. In children cryptosporidioses may be asymptomatic or lead to diarrhea especially in cases associated with malnutrition or immunodeficiency related in particular to AIDS. Helminths are a rare cause of significant diarrhea except Anguillula in undernourished children. In children presenting severe malnutrition, anguilluliasis can lead to serious consequences and requires immediate treatment using ivermectin. To avoid severe diarrhea in children presenting immunodeficiency induced by corticotherapy or chemotherapy for cancer, prophylaxis is mandatory against anguilluliasis using ivermectin and usually against giardiasis using metronidazole.