Seroepidemiological Study of Toxoplasma gondii Infection among Psychiatric Patients in Mashhad, Northeast of Iran

<p><strong><em>Background:</em></strong> Psychiatric patients have an increased risk of some infections like toxoplasmosis. Investigations on <em>Toxoplasma gondii</em> infection among psychiatric patients have been limited in Mashhad, Northeast of Iran. In this case-control study, prevalence of T. gondii was investigated by serological method.</p><p><strong><em>Methods:</em></strong> This case-control study was performed among psychiatric patients admitted to Avicenna Hospital in Mashhad, Northeast of Iran. Three hundred and fifty inpatients and 350 controls were examined in 2012-2013 for detection of IgG and IgM antibodies against <em>T. gondii </em>in their blood sera by ELISA. Socio-demographic and clinical manifestations of the patients were obtained.</p><p><strong><em>Results:</em></strong><strong> </strong>Anti-<em>T. gondii</em> IgG antibodies was found in 164 (46.85%) of 350 psychiatric inpatients and 120 (34.28%) of 350 controls. Seventeen (4.85%) of psychiatric individuals and 3 (0.85%) of control group were IgM+/IgG- indicating acute form of toxoplasmosis. There were no statistically significant differences between the case and control groups. In patient group, schizophrenic patients had the highest positive rate (46.28%) and bipolar mood disorder had the second most prevalent rate (20%). Of 162 schizophrenia patients, 65 (40.1%) had latent infection which was higher than that observed in controls.</p><p><strong><em>Conclusion:</em></strong><strong> </strong>The prevalence of <em>T. gondii</em> infection among psychiatric patients suffering from schizophrenia was more in Mashhad, compared with control group.