Original Article

Additional Glance on the Role of Dientamoeba fragilis & Blastocystis hominis in Patients with Irritable Bowel Syndrome


Background: Irritable bowel syndrome (IBS) is a functional gastrointestinal disease with high population prevalence. Dientamoeba fragilis and Blastocystis hominis are reported worldwide as a cause of human gastrointestinal symptoms. This study evaluated the possible link between this syndrome and the infection with D. fragilis and B. hominis in Egypt.

Methods: Overall, 310 stool samples (160 from IBS patients and 150 from controls) were obtained from Tropical Medicine Outpatient Clinic, Faculty of Medicine, Ain Shams University, Cairo, Egypt between Mar 2015 and Feb 2016. All the stool specimens underwent direct examination and Trichrome staining. Each sample was cultivated on Jones and Robinson's media.

Results: Overall, 42 cases (28%) showed B. hominis and 2 cases (1.3%) for D. fragilis infections. After performing the culture methods for B. hominis and D. fragilis, detections increased to 50 cases (33.3%) and 3 cases (2%), respectively. While among 150 controls 18 (12%) positive samples were detected as B. hominis.

Conclusion: There may be a possible relationship between the presentation of irritable bowel syndrome and D. fragilis and B. hominis infections, which have to be excluded first.

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IssueVol 13 No 1 (2018) QRcode
SectionOriginal Article(s)
Dientamoeba fragilis Blastocystis hominis Irritable bowel syndrome

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How to Cite
IBRAHIM AN, AL-ASHKAR AM, NAZEER JT. Additional Glance on the Role of Dientamoeba fragilis & Blastocystis hominis in Patients with Irritable Bowel Syndrome. Iran J Parasitol. 1;13(1):100-107.