Diagnosis: Gastrointestinal disease
• The life cycle of Dientamoeba fragilis does not include a cyst stage. The morphology of D. fragilis can be differentiated from that of Giardia intestinalis, as described in the table.
• The mode of transmission is through fecal-oral spread and sometimes through coinfected eggs of Enterobius vermicularis (pinworm).
• Disease is more common in children; adults are typically asymptomatically colonized.
• Examination of a single stool sample has a sensitivity of 50%; multiple samples (up to 6) are necessary to optimize detection.
• Common treatment strategies for D. fragilis infection include metronidazole, iodoquinol, and paromomycin.
