Entamoeba histolytica

Entamoeba histolytica. Cyst in formalin-preserved feces (iodine stain, oil immersion). This cyst contains a brown-staining glycogen mass. Although only one nucleus is visible, its small size suggests that another may be present in another plane of focus. This cyst can be differentiated from the typical uninucleate cyst of Iodamoeba buetschlii by the characteristic morphology of its nucleus.