Pediatric anti-N-methyl-D-aspartate receptor encephalitis-clinical analysis and novel findings in a series of 20 patients

J Pediatr. 2013 Apr;162(4):850-856.e2. doi: 10.1016/j.jpeds.2012.10.011. Epub 2012 Nov 16.

Abstract

Objective: To report the clinical features of 20 pediatric patients with anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis.

Study design: Review of clinical data, long-term follow-up, and immunologic studies performed in a single center in Spain in the last 4 years.

Results: The median age of the patients was 13 years (range, 8 months-18 years), 70% were female. In 12 patients (60%), the initial symptoms were neurologic, usually dyskinesias or seizures, and in the other 40% psychiatric. One month into the disease, all patients had involuntary movements and alterations of behavior and speech. All patients received steroids, intravenous immunoglobulin or plasma exchange, and 7 rituximab or cyclophosphamide. With a median follow up of 17.5 months, 85% had substantial recovery, 10% moderate or severe deficits, and 1 died. Three patients had previous episodes compatible with anti-NMDAR encephalitis, 2 of them with additional relapses after the diagnosis of the disorder. Ovarian teratoma was identified in 2 patients, 1 at onset of encephalitis and the other 1 year later. Two novel observations (1 patient each) include, the identification of an electroencephalographic pattern ("extreme delta brush") considered characteristic of this disorder, and the development of anti-NMDAR encephalitis as post herpes simplex encephalitis choreoathetosis.

Conclusions: The initial symptoms of pediatric anti-NMDAR encephalitis vary from those of the adults (more neurologic and less psychiatric in children), the development of a mono-symptomatic illness is extremely rare (except in relapses), and most patients respond to treatment. Our study suggests a link between post herpes simplex encephalitis choreoathetosis and anti-NMDAR encephalitis.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Anti-N-Methyl-D-Aspartate Receptor Encephalitis / blood*
  • Anti-N-Methyl-D-Aspartate Receptor Encephalitis / diagnosis*
  • Brain / pathology
  • Child
  • Child, Preschool
  • Female
  • Humans
  • Immunotherapy / methods
  • Infant
  • Magnetic Resonance Imaging / methods
  • Male
  • Pediatrics / methods
  • Spain
  • Time Factors
  • Treatment Outcome