Iodamoeba butschlii

Iodamoeba butschlii is an ameba that is considered nonpathogenic

Disease / Pathogenesis

Iodamoeba butschlii is nonpathogenic

Location in the Host

Iodamoeba butschlii is located in the lumen of the colon and cecum.

Geographic Distribution

Iodamoeba butschlii is found worldwide.

Life Cycle

Ingestion of the cyst stage of the ameba is the main form of transmission. The cyst stage will be found in contaminated water and food.

Image courtesy of CDC

Morphology & Diagnosis

Iodamoeba butschlii cyst and trophozoites can be detected in feces by performing an ova & parasite examination.

The trophozoites are 8-20u with a sluggish and nonprogressive movement. The karysome of the nucleus is characteristically large and centrally located. The nucleus contains no peripheral chromatin. Meanwhile the cytoplasm is coarsely granular and may contain debris such as vacuoles, bacteria, yeast.

The cyst is 5-20u and usually has a characteristic discrete glycogen mass in the cytoplasm. This glycogen mass takes up a large portion of the cyst. The cyst is round to ellipsoid in shape. Lugol’s iodine preps will stain the mass a dark brown color while trichrome staining will produce a light to minimal staining of the glycogen mass.


Iodamoeba butschlii cysts – note the prominent glycogen vacuole characteristic of the parasite. Photo by W. Vientos
Iodamoeba butschlii trophozoite in a trichrome stain preparation. Note the characteristic glycogen vacuole.
Iodamoeba butschlii cyst in a trichrome stain preparation. Note the characteristic glycogen vacuole.