Amebiasis.

Human amebiasis is caused by the protozoan parasite Entamoeba histolytica. Invasion of the colonic mucosa by the trophozoite form of this parasite generally results in the clinical syndrome of amebic dysentery, although there is a wide range of clinical presentations. Some patients will progress to disseminated disease, with resulting amebic liver abscesses. Although it is estimated that 10% of the world's population is infected with E. histolytica, only 1% of these patients will manifest disease. The diagnosis is usually made by microscopically identifying the microorganism in a stool specimen. The antibiotic of choice for treatment of amebiasis is metronidazole, 750 mg, three times daily for 10 days.