Does Dientamoeba fragilis cause diarrhea? A systematic review.

Area of Science:

• Medical Parasitology
• Gastroenterology
• Infectious Diseases

Background:

• Dientamoeba fragilis is an intestinal protozoan parasite.
• Its role in causing diarrhea is debated, with controversy over whether it acts as a commensal or a pathogen.

Purpose of the Study:

• To systematically review and evaluate the strength of evidence linking Dientamoeba fragilis infection to the development of diarrhea.
• To assess the evidence for Dientamoeba fragilis as a cause of diarrheal illness.

Main Methods:

• Systematic literature search for studies reporting D. fragilis detection in stools and association with diarrhea.
• Inclusion of studies on diarrhea outcomes related to D. fragilis therapy or challenge.
• Analysis of prevalence data from various study populations and diagnostic settings.

Main Results:

• Prevalence of D. fragilis in stools varied across studies (1.6% to 22%).
• Diarrhea association with D. fragilis detection was inconsistent across different study types and populations.
• Limited evidence from cohort and challenge studies; no treatment studies reported diarrhea as an outcome.

Conclusions:

• The current evidence is insufficient to definitively conclude that Dientamoeba fragilis causes diarrhea.
• The data do not support that treatment for D. fragilis hastens diarrhea resolution.
• Further robust research is required to clarify the pathogenic role of D. fragilis.