Entamoeba gingivalis

Entamoeba gingivalis. Trophozoite in smear of tartar material from around teeth (iron hematoxylin stain, oil immersion). This trophozoite shows a prominent nucleus containing a punctate karyosome and fine, evenly distributed peripheral chromatin. The densely staining round bodies within food vacuoles in the cytoplasm are degenerating leukocytes. The nucleus of this species closely resembles the nucleus of E. histolytica, but the source of the organism from the mouth and the presence of ingested leukocytes differentiates it from E. histolytica. E. gingivalis has no cyst stage. This organism also has been reported infrequently in vaginal and cervical smears from women who use intrauterine contraceptive devices.