Objective: Blastocystis spp; is a protozoon that can be seen worldwide. Fecal-oral transmission is the most accepted pathway for Blastocystis spp. infection. Most infected patients show no symptoms of infection, however it can cause abdominal pain, acute or chronic diarrhea, vomiting, flatulence and nausea. It is suggested that Blastocystis spp. may cause several pathologies in gut causing an inflammatory response that may lead to Inflammatory Bowel Diseases.