Seropositivity of toxoplasmosis in patients with schizophrenia.

Recent studies indicate that infectious agents may contribute to some cases of schizophrenia. In animals, infections with Toxoplasma gondii can alter behavior and neurotransmitter function. In humans, acute infection can produce psychotic symptoms similar to those displayed by persons with schizophrenia. In the present study, an enzyme immunoassay (EIA) was employed to measure the level of Toxoplasma IgG antibodies in serum samples from 75 patients of schizophrenia and 85 matched controls. Percentage of positive sera for Toxoplasma IgG antibodies was significantly higher in schizophrenic cases than controls (80% vs. 52.9% respectively). Infection increased with age in both groups and no significant association was found with sex. No association was found with duration of illness or presence of family history of schizophrenia. Circumstantial evidence indicates that infection with Toxoplasma gondii may lead to some cases of schizophrenia.