Dientamoeba fragilis

Dientamoeba fragilis

Dientamoeba fragilis was initially classified as an amoeba; however, the internal structures of the trophoziote are typical of a flagellate. No cyst stage has been described. The life cycle and mode of transmission of D. fragilis are not known. It has worldwide distribution. The transmission is postulated, via helminthes egg such as those of Ascaris and Enterobius species. Transmission by faecal- oral routes does occur. Most infection with D. fragilis is asymptomatic, with colonization of the cecum and upper colon. However, some patients may develop symptomatic disease, consisting of abdominal discomfort, flatulence, intermittent diarrhea, anorexia, and weight loss. 

The therapeutic agent of choice for this infection is iodoquinol, with tetracycline and parmomycine as acceptable alternatives. The reservoir for this flagellate and  lifecycle are unknown. Thus, specific recommendation for prevention is difficult. However, infection can be avoided by maintenance of adequate sanitary conditions.