Serological survey of Toxoplasma gondii in schizophrenia patients referred to Psychiatric Hospital, Sari City, Iran.

Schizophrenia is a severe neuropsychiatric disorder of unknown etiology. As there is little information about the association between Toxoplasma gondii infection and schizophrenia in Iran, we investigated the seroprevalence of T. gondii in these patients and compared with that obtained in control individuals in Sari City, Iran, 2009. Eighty schizophrenia patients and 99 healthy people were examined for the presence of IgG and IgM antibodies to T. gondii by enzyme linked immunosorbent assay (ELISA). Overall prevalence rates of anti-T. gondii antibodies (IgG/IgM) in case and control groups were 72.5% and 61.6%, respectively (P>0.05). IgG antibodies indicating chronic form of toxoplasmosis were found in 28 (35%) and 25 (25.3%) of case and control groups, respectively (P>0.05). IgM antibodies (acute form) were also seen in 9 (11.2%) and 11 (11.1%) of case and control individuals, respectively (P>0.05). The highest 10th percentile of IgG titers in schizophrenia individuals (18.8%) was significantly higher than control group (6.1%, P=0.02). As prevalence rate of T. gondii antibodies in patients with schizophrenia was high, it seems that designing a cohort study will determine the causative relationship between Toxoplasma infection and schizophrenia.