Arnebiasis is caused by £. tnstolytica. which is the only species pathogenic in humans, while the patbogeneicity of £. dispor and£. moshkuvskii is still unclear. The disease is endemic in the developing countries, mainly due to poor sanitation and lack of clean water supplies. Infection occurs by ingestion of£. histolytica cysts in fecally contaminated food or water. Excystation in the smal…