Dientamoeba fragilis

Dientamoeba fragilis and Entamoeba histolytica. Trophozoites and cysts in fecal smear (trichrome stain, oil immersion). A binucleate trophozoite of D. fragilis lies above an immature cyst of E. histolytica and to the left of a somewhat obscure trophozoite of E. histolytica. It is difficult to see nuclear detail in the E. histolytica trophozoite. A second immature cyst of E. histolytica lies to the left of the other E. histolytica cyst. In both of these immature cysts, a large vacuole is present and chromatoid bodies are arranged at the periphery. The nuclei of both cysts are not seen.