Dientamoeba Fragilis Infection Clinical Presentation

Updated: Jul 31, 2018
  • Author: Maria A Garcia Fernandez, MD; Chief Editor: Russell W Steele, MD  more...
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Abdominal pain and diarrhea are the most common symptoms in patients with Dientamoeba fragilis infection. [6] In acute infection, diarrhea is the predominant symptom, which lasts 1-2 weeks. [7] Diarrheal history may vary, with either consistently frequent stools (1-4 stools per day) or episodic occurrence of diarrhea. Stools are greenish brown, and their consistency varies from watery to sticky. Occasionally, mucus is noted in the stools, but hematochezia is unusual. Chronic infection is diagnosed when duration of symptoms is greater than 1-2 months. The most common symptom in chronic infection is abdominal pain.

Other GI complaints include the following [8] :

  • Anorexia

  • Weight loss

  • Nausea

  • Vomiting

  • Bloating

  • Flatulence

  • Alternating constipation and diarrhea

Nonintestinal complaints include the following:

  • Headache

  • Fever

  • Malaise

  • Fatigue

  • Irritability

  • Weakness

  • Pruritus



Nonspecific findings are present on physical examination though general abdominal tenderness may be noted in some children.



The mode of transmission is believed to be through direct fecal-oral spread and, possibly, through the eggs of E vermicularis (pinworm). Pigs have recently been identified as a natural host for D fragilis, [3] raising the possibility of transmission from porcine waste and the parasite has also been identified in untreated wastewater. [1]