Childhood Anti-NMDA Receptor Encephalitis

Abstract

Objectives: To study the clinical profile, and outcome of children with anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis. Methods: This is a retrospective case series of children <12 y of age, diagnosed with anti-NMDAR encephalitis at a tertiary care institute during the period, May 2013 through June 2015. Results: Twenty patients were tested for suspected anti-NMDAR encephalitis over this 2 y period. Of these, six children were positive for anti-NMDAR antibodies. Four of these six children had completed treatment and two are currently receiving immunotherapy. Behavioral changes, psychosis, seizures and oro-lingual-facial dyskinesia were the presenting features. Extreme irritability, insomnia and mutism were noted in all the children. The symptoms were persistent, and the course was progressive over 4–8 wk duration. Neuroimaging and electroencephalography were non-specific. Intravenous pulse methylprednisolone and immunoglobulins were used as first-line therapeutic agents. Only one patient responded to first line immunotherapy; five out of six children required second-line immunotherapy. One patient recovered following rituximab, and two patients showed a good response to cyclophosphamide pulse therapy; two patients are currently under treatment with second line immunotherapeutic agents. Tumor screen was negative in all children. Conclusions: Anti-NMDAR encephalitis is rare but a potentially treatable condition. Timely recognition is essential because treatment is entirely different from other viral encephalitis. Aggressive immunotherapy is the key to a favourable outcome.