The relationship between blastocystis hominis infection and Irritable Bowel Syndrome (IBS) and comparing direct wet mount, stool culture, Formalin- Ether and trichrome staining procedures for identifying organisms

Introduction: Blastocystis hominis is a parasite found in the stools of human as well as in the stools of other animals and recently its pathogenic potential has been increasingly recognized. Irritable Bowel Syndrome (IBS) is a digestive system’s disorder which is featured by change in bowel habits, abdominal pains and other symptoms similar to Blastocystis hominis infection. There is little information about this syndrome and its etiology is still unknown. This study aims at analyzing the relationship between Blastocystis hominis and IBS. Methods: In a case-control study, a total of 81 patients with IBS and 81 patients with other digestive disorders, but without IBS, who had referred to Shahid Beheshti Hospital in Hamedan City, were selected. The disease was diagnosed by a gastroenterologist in terms of the relevant criteria. Blastocystis hominis infection in this study was diagnosed using stool test through four techniques: direct wet mount, stool culture, formalin-ether concentration and trichrome staining. Results: Totally, 43 women (53%) and 38 men (47%), in the age range of 13 to 64 years old, participated in this study. Using the stool culture technique, as the golden standard, infection in 37 members (45.67%) of the case group and 18 members (22.22%) of the control group was reported, which this difference was significant, statistically (P<0.001). There was difference between case and control groups in terms of Blastocystis infection with all four techniques. Conclusion: The results of this study indicated that since the infection rate in the case group was higher than that in the control group, a relationship between Blastocystis hominis infection and IBS is possible. Speaking about infection diagnosis, culture technique was more sensitive than other techniques used to diagnose Blastocystis hominis infection.