Dientamoeba fragilis Infection
(DYE-ent-a-ME-ba fra-JILL-us)

What is Dientamoeba fragilis?

Dientamoeba fragilis is a parasite that lives in the large intestine of humans. Infection occurs worldwide and is commonly diagnosed in the United States.

What are the symptoms of infection with Dientamoeba fragilis?

Loose stools, diarrhea, and abdominal cramping are the most common symptoms. Loss of weight and appetite, abdominal tenderness, and fatigue have also been reported among people who have D. fragilis. Many people have no symptoms at all.

What should I do if I think I have the parasite Dientamoeba fragilis?

See your health care provider.

How is infection with Dientamoeba fragilis diagnosed?

Your health care provider will ask you to provide stool samples for testing. Diagnosis may be difficult, so you may be asked to submit more than one sample.

Is medication available to treat infection with Dientamoeba fragilis?

Yes. Safe and effective drugs are available.

I have been sick and have recently been diagnosed with Dientamoeba fragilis. Should I be treated?

Yes.

Who is at greatest risk for infection?

Those at highest risk for infection are people who live in institutions that have poor sanitary conditions and travelers who visit developing countries.

How did I get Dientamoeba fragilis?

How D. fragilis is spread is uncertain, but infection is likely:

1. By touching and bringing to your mouth anything, such as fingers, that have touched the stool of a person infected with D. fragilis.
2. By swallowing something, such as water or food, contaminated with D. fragilis.
3. By touching and bringing to your mouth D. fragilis picked up from contaminated surfaces.

How can I prevent Dientamoeba fragilis infection?

• Wash your hands with soap and warm water, especially after using the toilet, changing baby diapers, and before preparing foods.
• Teach children the importance of washing hands to prevent infection.

For more information:

1. Spencer MJ, Chapin MR, Garcia LS. Dientamoeba fragilis: a gastrointestinal protozoan infection in adults. Am J Gastroenterol 1982;77:565-9.
2. Spencer MJ, Garcia LS, Chapin MR. Dientamoeba fragilis: an intestinal pathogen in children? Am J Dis Child 1979;133:390-3.
3. Yang J, Scholten T. Dientamoeba fragilis: a review with notes on its epidemiology, pathogenicity, mode of transmission and diagnosis. Am J Trop Med Hyg 1977;26:16-22.

This fact sheet is for information only and is not meant to be used for self-diagnosis or as a substitute for consultation with a health care provider. If you have any questions about the disease described above or think that you may have a parasitic infection, consult a health care provider.