Entamoeba histolytica/dispar: Cysts measure 10 to 20 microns. The four nuclei in this cyst is typical of these species. To count all four nuclei requires focusing up and down through the cyst. This changing of focal planes also helps show the chromatoid body as a cigar shaped object with rounded ends.
This microphotographic image was taken at the Oregon State Public Health Laboratory. The OSPHL Parasitology Department is equipped with a Leica DC 200 digital camera mounted on a Leica DMLS microscope. This equipment is used in conjunction with the Division of Parasitic Diseases (DPDx) at the Centers for Disease Control & Prevention (CDC) to aid in the rapid diagnosis of unusual or difficult parasitic diseases using digital images and the Internet.