Atypical psychiatric presentation of relapsing anti-N-methyl-D-aspartate receptor encephalitis in childhood

Anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis is an autoimmune encephalitis caused by antibodies (Ab) against the GluN1 subunit of the NMDAR. The disease typically presents with a combination of psychiatric and neurological symptoms. Presentation solely with psychiatric symptoms is rare, especially in childhood. After treatment substantial recovery with mild or no residual symptoms is seen in most cases in both children and adults. Relapse occurs in 10%-25% of patients, with recurrent episodes presenting less severe than initial presentation in most cases. We herein describe a child with a pure psychiatric presentation of anti-NMDAR encephalitis. Diagnosis and treatment was delayed because of the atypical presentation. The child relapsed several times and severe residual psychiatric symptoms persisted after recovery. This case illuminates the need to consider the diagnosis of anti-NMDAR encephalitis in both adults and children with an atypical psychiatric presentation. It also demonstrates the need for a multidisciplinary approach and brings attention to the possible severe impact of the disease on long-term psychosocial functioning.