title: Severe childhood encephalopathy with dyskinesia and prolonged cognitive disturbances: evidence for anti-N-methyl-D-aspartate receptor encephalitis.
abstract: OBJECTIVE
  We report four cases of acquired severe encephalopathy with massive hyperkinesia, marked neurological and cognitive regression, sleep disturbance, prolonged mutism, and a remarkably delayed recovery (time to full recovery between 5 and 18mo) with an overall good outcome, and its association with anti-N-methyl-d-aspartate (anti-NMDA) receptor antibodies.
  
  
  METHODS
  We reviewed the four cases retrospectively and we also reviewed the literature.
  
  
  RESULTS
  Anti-NMDA receptor antibodies (without ovarian teratoma detected so far) were found in the two children tested in this study.
  
  
  CONCLUSIONS
  The clinical features are similar to those first reported in 1992 by Sebire et al.,(1) and rarely recognized since. Sleep disturbance was not emphasized as part of the disorder, but appears to be an important feature, whereas coma is less certain and difficult to evaluate in this setting. The combination of symptoms, evolution (mainly seizures at onset), severity, paucity of abnormal laboratory findings, very slow recovery, and difficult management justify its recognition as a specific entity. The neuropathological substrate may be anatomically close to that involved in encephalitis lethargica, in which the same target functions (sleep and movement) are affected but in reverse, with hypersomnolence and bradykinesia. This syndrome closely resembles anti-NMDA receptor encephalitis, which has been reported in adults and is often paraneoplastic.
authors.affiliation: Department of Paediatrics, Child Neurology, University Hospital Lausanne, Lausanne, Switzerland.
authors.forename: Claudia
authors.initials: C
authors.lastname: Poloni
authors.forename: Christian M
authors.initials: CM
authors.lastname: Korff
authors.forename: Valeria
authors.initials: V
authors.lastname: Ricotti
authors.forename: Mary D
authors.initials: MD
authors.lastname: King
authors.forename: Eliane Roulet
authors.initials: ER
authors.lastname: Perez
authors.forename: Claire
authors.initials: C
authors.lastname: Mayor-Dubois
authors.forename: Charles-Antoine
authors.initials: CA
authors.lastname: Haenggeli
authors.forename: Thierry
authors.initials: T
authors.lastname: Deonna
mesh_terms: D001323:Autoantibodies / Q000097:blood; D001921:Brain / Q000473:pathology / Q000503:physiopathology; D002648:Child; D002675:Child, Preschool; D003072:Cognition Disorders / Q000209:etiology* / Q000503:physiopathology; D020820:Dyskinesias / Q000209:etiology* / Q000503:physiopathology; D004569:Electroencephalography; D004660:Encephalitis / Q000150:complications* / Q000175:diagnosis / Q000276:immunology / Q000473:pathology / Q000503:physiopathology; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D009155:Mutism / Q000209:etiology; D011379:Prognosis; D016194:Receptors, N-Methyl-D-Aspartate / Q000276:immunology*; D012189:Retrospective Studies; D012720:Severity of Illness Index; D012893:Sleep Wake Disorders / Q000209:etiology* / Q000503:physiopathology; D013997:Time Factors
chemical_list: D001323:Autoantibodies; D016194:Receptors, N-Methyl-D-Aspartate