Razi Journal of Medical Sciences

    Background & Aim: Blastocystis hominis is an intestinal parasite in humans and animals. Despite extensive studies, pathogenic role of this organism is controversial. Prevalence rate of contamination with this organism varies from 1.5% to 10% in developed countries and reaches up to 50% in developing countries. The purpose of this study was to investigate total IgG, total IgA and IgG2 subclass in adults infected with Blastocystis hominis and compare them with healthy individuals. Patients and Method: In this cross-sectional case-control study, we selected 100 adults infected with Blastocystis hominis and 100 healthy subjects referred to health service sectors of Iran University of Medical Sciences and Milad Hospital. Serum immunoglobulin examinations were performed by means of nephelometry and Minineph human Ig kit made by the Binding Site Ltd., Birmingham, UK. Data analysis was done by SPSS version 12 and independent t-test. Results: According to the obtained results, there was no significant difference in the level of total IgA between the case and control groups(t=409, P=0.683), but the levels of total IgG and IgG2 subclass showed a significant difference between the case and control groups(IgG: t=2.83, P= 0.005 IgG2: t= 2.02, P= 0.002). Conclusion: The results showed that the immune system response to carbohydrate and glycogenic antigens of the central vacuole of this protozoon leads to an increase in the level of serum IgG especially IgG2 subclass.