REM and NREM Sleep Parasomnia in Anti-NMDA Receptor Encephalitis

OBJECTIVES:Encephalitis with anti-N-methyl-d-aspartate receptor antibodies (anti-NMDARe) is a rare disorder characterized by cognitive impairment, psychosis, seizures, and abnormal movements. Abnormal behaviors during REM sleep have not been described in anti-NMDARe. METHODS:Patients were monitored by video-polysomnography on a first night followed by multiple sleep latency tests and 18 hours of bed rest. RESULTS:Two patients with anti-NMDARe developed during the acute and postacute phase parasomnias including REM sleep behavior disorder and continuous finalistic quiet gesturing during a mixed N2/R sleep. The parasomnia disorder was improved by gabapentin and clonazepam. DISCUSSION:Video-polysomnography avoids misdiagnosing these parasomnia behaviors for seizure or movement disorders and allows adequate treatment.