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Left: E. polecki cyst stained with trichrome. Right: I. buetschlii cyst stained with trichrome.

Nonpathogenic intestinal protozoa are single-celled parasites commonly found in the intestinal tract but never associated with illness. They do not harm the body, even in people with weak immune systems. Symptomatic people who are found to have these protozoa in their stool should be examined for other causes of their symptoms.

The nonpathogenic intestinal protozoa include:

  • Chilomastix mesnili
  • Endolimax nana
  • Entamoeba coli
  • Entamoeba dispar
  • Entamoeba hartmanni
  • Entamoeba polecki
  • Iodamoeba buetschlii

Image: Left: Entamoeba polecki cyst stained with trichrome. Right: Iodamoeba buetschlii cyst stained with trichrome. (Credit: DPDx)

  • Page last reviewed: December 14, 2012
  • Page last updated: December 14, 2012
  • Content source:
    • Global Health - Division of Parasitic Diseases and Malaria
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