Microsporidia are a group of eukaryotic obligate intracellular parasites that infect most invertebrates and all classes of vertebrates, including man. In human population, microsporidia are emerging as opportunistic pathogens in immunocompromised patients. Two groups of human sera (318 serum samples) were tested by ELISA for the presence of specific antimicrosporidial (anti-Encephalitozoon intestinalis) antibodies. Group 1 included 120 patients with secondary immunodeficiency, group 2 consisted of 198 immunocompetent controls. Anti-Encephalitozoon intestinalis antibodies were detected in 29 (24.16 %) patients and 20 (10.1 %) immunocompetent controls. The difference in prevalence of antibodies against Encephalitozoon intestinalis between the groups was statistically significant (P<0.05 %).

        Key words: microsporidia – Encephalitozoon intestinalis – immunodeficiency – antibodies – ELISA.