Endolimax nana

Endolimax nana. Trophozoites in fecal smear (trichrome stain, oil immersion). Trophozoites may vary in size; in this field a small and large trophozoite lie adjacent to each other. The smaller trophozoite has a typical large and round, red-staining karyosome, whereas in the larger organism, the karyosome is bandlike and skewed to lie against the nuclear membrane. Aberrations in the morphology and the positioning of the karyosome are common in this species.