Autoimmune psychosis: Psychopathological patterns and outcome after immunotherapy.

BACKGROUND

The diagnostic criteria for "autoimmune psychosis" have been proposed to identify patients presenting with psychotic symptoms of autoimmune origin. Here, we aim to characterize the psychopathological features and outcomes of patients diagnosed with autoimmune psychosis.

METHODS

We describe a cohort study conducted at the National Institute of Neurology and Neurosurgery of Mexico, including patients with psychotic symptoms exhibiting features of possible autoimmune psychosis: a) catatonia, b) dyskinesia, c) seizures, d) signs of neuroleptic malignant syndrome or clinical worsening after use of antipsychotics, or e) severe cognitive impairment.

RESULTS

Of 195 psychotic patients under assessment, 164 patients were diagnosed as having psychosis of autoimmune origin and received immunotherapy. Hallucinations were present in 83 %, delusions in 77 %, and disorganized speech in 64 % of the cases. Severe cognitive dysfunction was present in 75 % while 64 % were diagnosed with catatonia. Seizures were the most common neurological feature (63 %), followed by movement disorders and autonomic abnormalities. Most patients (71%) were diagnosed as having definite anti- NMDAR encephalitis. A significant proportion of the cases (39 %) had been previously misdiagnosed as having a primary psychiatric disorder. After immunotherapy, most patients with anti-NMDA receptor encephalitis, or with a negative determination of NMDA receptor antibodies, experienced cognitive and functional improvement, and a significant reduction in psychotic symptoms.

CONCLUSIONS

Our study supports previous observations about the value of the autoimmune psychosis construct, the pleomorphic psychopathological patterns of autoimmune encephalitis, and the significant improvement of psychopathology after immunotherapy.