A case-control study of Blastocystis hominis among Iranian population.

OBJECTIVES

A case-control study was conducted to investigate the epidemiology and clinical features of Blastocystis hominis among Iranian patients with and without GI symptoms.

METHODS

Six hundred and seventy patients with GI and Six hundred and seventy patients without GI symptoms were enrolled as cases and controls respectively during 2006-07. Standard microscopic examinations following in vitro culture were used to examine the stool samples for presence of trophozoites and cysts of B. hominis.

RESULTS

Infection with B. hominis occurred most commonly in those with GI symptoms (5.67 %) compared with those patients without GI symptoms (3.43 %). The most common symptom in case group was abdominal pain (86.84 %). B. hominis was mostly found with Giardia lamblia in case group and with Entamoeba coli in control group. In addition, there was no significant relation between the presence of GI symptoms and the incidence of B. hominis.

CONCLUSION

B. hominis has long been described as a non-pathogenic protozoan parasite until recently, when claims have been made that it could result in pathogenic conditions. Thus, to confirm the complication is needed to additional study especially on molecular pathogenesis of this organism.