- Entamoeba coli, E. hartmanni, E. polecki, Endolimax nana, and Iodamoeba buetschlii are generally considered nonpathogenic and reside in the large intestine of the human host .
- Both cysts and trophozoites of these species are passed in stool and considered diagnostic .
- Cysts are typically found in formed stool, whereas trophozoites are typically found in diarrheal stool.
- Colonization of the nonpathogenic amebae occurs after ingestion of mature cysts in fecally-contaminated food, water, or fomites .
- Excystation occurs in the small intestine and trophozoites are released, which migrate to the large intestine.
- The trophozoites multiply by binary fission and produce cysts, and both stages are passed in the feces .
- Because of the protection conferred by their cell walls, the cysts can survive days to weeks in the external environment and are responsible for transmission.
- Trophozoites passed in the stool are rapidly destroyed once outside the body, and if ingested would not survive exposure to the gastric environment.
- Both cysts and trophozoites of these species are passed in stool and considered diagnostic .
- Cysts are typically found in formed stool, whereas trophozoites are typically found in diarrheal stool.
- Colonization of the nonpathogenic amebae occurs after ingestion of mature cysts in fecally-contaminated food, water, or fomites .
- Excystation occurs in the small intestine and trophozoites are released, which migrate to the large intestine.
- The trophozoites multiply by binary fission and produce cysts, and both stages are passed in the feces .
- Because of the protection conferred by their cell walls, the cysts can survive days to weeks in the external environment and are responsible for transmission.
- Trophozoites passed in the stool are rapidly destroyed once outside the body, and if ingested would not survive exposure to the gastric environment.