Clinical And Electrophysiological Studies Of Anti-N-methyl D-aspartate Receptor Encephalitis In Children

PART 1.Clinical study of 20 children with anti-NMDA receptor encephalitisObjectiveTo assess the presentation of Anti-NMDA receptor(NMDAR)encephalitis,the spectrum of symptoms,immunotherapies used,timing of improvement,and long-term outcome in childrenMethodsIn this observational study,we tested the presence of NMDAR antibodies in serum or CSF samples of patients with encephalitis treated in Neurology Department of Capital Institute of Pediatrics between Dec 1,2011,and Decl,2014.All patients who tested positive for NMDAR antibodies were included in the study;patients were assessed at symptom onset and at months 4,8,12,18,24,and 36 by use of the modified Rankin scale(mRS).Treatment included first-line immunotherapy(steroids,intravenous immunoglobulin),second-line immunotherapy(most of them are intravenous rituximab).ResultsWe enrolled 20 patients(range 1 year 11 months to 13 years 4 months),observation time range 8 months to 3 years 6 months.All Patients present with acute neurology symptoms:90%with seizures.Speech problems,memory deficit,dyskinesias are quite popular in these children.Cerebellar ataxia and hemiparesis are not uncommon in children younger than 6 years.20 patients underwent first-line immunotherapy,resulting in improvement within 4 weeks in 10(50%).10 patients who did not improve with first-line treatment received second-line immunotherapy,8 of them resulted in a better outcome.Outcomes may continued to improve for up to 8 months to 1 year after symptom onset.Conclusions anti-NMDAR encephalitis are not rare in children.Most patients with anti-NMDAR encephalitis respond to immunotherapy.Second-line immunotherapy is usually effective when first-line treatments fail.PART 2Electroencephalography study of 20 children with anti-NMDA receptor encephalitisObjectiveTo evaluate the EEG findings of children with Anti-NMDA receptor(NMDAR)encephalitis,and the relation between the EEG changes and the clinical findings.MethodsIn this observational study,we tested the presence of NMDAR antibodies in serum or CSF samples of patients with encephalitis treated in Neurology Department of Capital Institute of Pediatrics between Dec 1,2011,and Dec l,2014.All patients who tested positive for NMDAR antibodies were included in the study;patients underwent video EEG in psychiatric/epileptic stages,non-responsible stages,and recover stages.The EEG and clinical data were analyzed to find the characteristic of EEG and the changes in different stages of the disease.ResultsWe enrolled 20 patients(range 1 year 11 months to 13 years 4 months),observation time range 8 months to 3 years 6 months.We got 25 Video-EEG during psychiatric/epileptic stage,23 of them were abnormal;17 Video-EEG of non-responsible stage,and none were normal;and 13 video-EEG of recovery stage.The most popular findings in EEG is the increase of slow waves,may combined with asymmetry of both sides,excess beta activity,and spikes.The most prominent EEG finding in non-responsive stage was diffuse delta activity,and the frequency of the waves were decreased as the time went.Extreme delta brush were rare in all the EEGs.Conclusion:The most prominent EEG finding in children with anti-NMD A-receptor encephalitis was increase of waves with the time.As the clinical symptom got more severe,the waves were more prominent and had lower frequency;and decreased as the children recovered.Different from the adults,EDB were rare in children.