Prevalence and clinical features of psychotic states associated with antibodies to NMDA receptors
Antibodies against NMDA receptors can cause severe autoimmune disorder (anti-NMDA receptor encephalitis) that could have predominantly psychiatric presentations. Aim. To assess the prevalence and clinical features of psychotic disorders associated with antibodies against NMDA receptors. Materials and methods. Patients with first episode psychosis and healthy controls were included in the study. All patients underwent psychopathological and psychometric assessment. Tests for antibodies against NMDA receptors were carried out by methods developed in the V. Serbsky National Medical Research Centre for Psychiatry and Narcology. Results. Antibody detection methods need to be improved. Our data suggests that serum NMDA receptor antibody levels could be measured via enzyme-linked immunosorbent assay as primary screening. Antibodies against NMDA receptors are detected in about 2% of patients with new-onset psychosis. Acute onset and predominance of catatonic symptoms are probably a risk factor for the autoimmune pathology. Conclusion. Some clinical features of psychotic disorders require screening for NMDA receptor antibodies to exclude autoimmune disorders.