Association between latent toxoplasmosis and clinical course of schizophrenia - continuous course of the disease is characteristic for Toxoplasma gondii-infected patients

Abstract

The aim of the present study was to investigate the association between various clinical aspects of schizophrenia and seropositivity against Toxoplasma gondii (Nicolle et Manceaux, 1908). We selected 94 patients with schizophrenia and investigated the seropositivity rate for anti-T. gondii IgG antibodies by ELISA. Clinical parameters of schizophrenic patients such as illness type and status, clinical course, awareness of the illness and need for electroconvulsive therapy (ECT) were compared with their serological status. Anti-T. gondii IgG antibodies were detected in 43 (46%) of schizophrenic patients. Chronic patients had a rate of 34 (72%) seropositivity, whereas 9 (22%) of the patients with partial remission showed evidence of latent toxoplasmosis. Of continuous patients, 35 (81%) were found to be seropositive and this rate was significantly more than in the other groups. The rate of latent toxoplasmosis was detected significantly higher in patients who lack awareness of schizophrenia (36, i.e. 72%) than the patients who were aware of their illnesses (7, i.e. 16%). Anti-T. gondii IgG antibodies were detected in 38 (70%) of ECT performed patients while this percentage was 13% in the ones who had never been treated with ECT. This difference was also statistically significant. We showed that Toxoplasma-infected subjects had 15× higher probability of having continuous course of disease than Toxoplasma-free subjects. Our results put forth the possibility of latent toxoplasmosis to have a negative impact on the course of schizophrenia and treatment response of schizophrenic patients.

Negative Effects of Latent Toxoplasmosis on Mental Health

“…It has even been documented that the changes in brain morphology that are characteristic of schizophrenia, such as gray matter reduction in frontal and temporal cortices, caudate, median cingulate, and thalamus, are in fact typical for Toxoplasma-seropositive schizophrenia patients (6). Congruently, the Toxoplasma-seropositive patients express more prominent positive symptoms of schizophrenia (7,8) and have a 15-times higher probability of having a continuous course of disease than the Toxoplasma-free patients (9). Far fewer studies have shown the association of toxoplasmosis with other mental health disorders.…”

Association of Toxoplasma gondii infection with schizophrenia and its relationship with suicide attempts in these patients

“…Regarding schizophrenia, the clinical picture of schizophrenia in toxoplasma‐infected and toxoplasma‐free patients differs in several respects. Toxoplasma‐infected individuals show more severe positive symptoms of schizophrenia and are more likely to experience a continuous course of disease than toxoplasma‐free patients . Several studies investigating the relationship between T. gondii and suicide in infected persons or in patients with schizophrenia gave inconclusive results .…”

Toxoplasma gondii infection and chronic schizophrenia: is there any association?

“…gondii infection has been associated with symptom severity in schizophrenia 23,27,28 . In addition, latent toxoplasmosis may have a negative impact on the disease course and treatment response in patients with schizophrenia 29 . Corroborating these clinical data, patients with schizophrenia T. gondii-seropositive presented more significant morphological changes in the caudate, cingulate, thalamus and occipital cortex in comparison with seronegative patients 30 .…”