Incidence and Clinical Profile of Anti-N-Methyl-D-Aspartate Receptor Encephalitis in Children

Abstract

BACKGROUNDEncephalitis in children is associated with high rate of morbidity and mortality. Many sporadic cases of encephalitis in children have recently been found to be CSF negative for infective markers. Antibodies against neuronal proteins in CSF are being detected more frequently in such patients and are well responsive to immunotherapy, if timely diagnosed. Anti-N-Methyl-D-Aspartate receptor (anti-NMDA) antibody mediated encephalitis is the most common in children among this group.The objective of this study was to determine the incidence and clinical profile of anti-NMDA antibody mediated encephalitis in children and its early (6-8 weeks) and late (1 year) treatment responses. MATERIALS AND METHODSIt was a descriptive study done in a tertiary care teaching hospital in south India. All children, 3 months to 12 years, presenting as acute encephalopathy, from January 2012 to December 2014 were evaluated and those with CSF anti-NMDA antibody positive children were treated with standard protocol and followed up at 6 weeks, 8 weeks and one year. RESULTSWe had 178 children presented as acute encephalitis during the 3-year period. 18 (10%) children were positive for anti NMDA antibody in CSF. Female gender predominated by 89%. Predominant clinical features were in the descending order, behaviour and psychiatric 89%, speech dysfunction 72 %, movement disorders 56%, seizures 22% and autonomic phenomena 6%. Majority (78%) responded completely to immunotherapy. CONCLUSIONAnti-NMDA receptor encephalitis is not rare in children. In children presenting as acute encephalitis with predominant neuropsychiatric symptoms or if CSF negative for infection, NMDA antibody test in CSF is a must. Prompt diagnosis is important because it is amenable to immunotherapy and longterm prognosis is very good.