title: Etiological associations and outcome predictors of acute electroencephalography in childhood encephalitis.
abstract: To examine EEG features in a retrospective 13-year cohort of children with encephalitis.
  
  
  
  354 EEGs from 119 patients during their admission were rated blind using a proforma with demonstrated inter-rater reliability (mean k=0.78). Patients belonged to 12 etiological groups that could be grouped into infectious and infection-associated (n=47), immune-mediated (n=36) and unknown (n=33). EEG features were analyzed between groups and for risk of abnormal Liverpool Outcome Score and drug resistant epilepsy (DRE) at last follow up.
  
  
  
  86% children had an abnormal first EEG and 89% had at least one abnormal EEG. 55% had an abnormal outcome, and 13% had DRE after median follow-up of 7.3years (2.0-15.8years). Reactive background on first EEGs (9/11, p=0.04) and extreme spindles (4/11, p<0.001) distinguished patients with anti-N-Methyl-d-Aspartate Receptor encephalitis. Non-reactive EEG background (48% first EEGs) predicted abnormal outcome (OR 3.8, p<0.001). A shifting focal seizure pattern, seen in FIRES (4/5), anti-voltage gated potassium channel (2/3), Mycoplasma (1/10), other viral (1/10) and other unknown (1/28) encephalitis, was most predictive of DRE after multivariable analysis (OR 11.9, p<0.001).
  
  
  
  Non-reactive EEG background and the presence of shifting focal seizures resembling migrating partial seizures of infancy are predictors of abnormal outcome and DRE respectively in childhood encephalitis.
  
  
  
  EEG is a sensitive but non-discriminatory marker of childhood encephalitis. We highlight the EEG features that predict abnormal outcome and DRE.
authors: Neuroimmunology Group, Institute of Neuroscience and Muscle Research at The Kids Research Institute, The Children's Hospital at Westmead, University of Sydney, Australia. Electronic address: shekeeb.mohammad@health.nsw.gov.au.
authors: Shekeeb S
authors: SS
authors: Mohammad
authors: TY Nelson Department of Neurology and Neurosurgery, The Children's Hospital at Westmead, Sydney, Australia. Electronic address: samantha.soe@health.nsw.gov.au.
authors: Samantha M
authors: SM
authors: Soe
authors: Neuroimmunology Group, Institute of Neuroscience and Muscle Research at The Kids Research Institute, The Children's Hospital at Westmead, University of Sydney, Australia. Electronic address: norwestpaedneurology@gmail.com.
authors: Sekhar C
authors: SC
authors: Pillai
authors: Neuroimmunology Group, Institute of Neuroscience and Muscle Research at The Kids Research Institute, The Children's Hospital at Westmead, University of Sydney, Australia. Electronic address: margherita.nosadini@gmail.com.
authors: Margherita
authors: M
authors: Nosadini
authors: NHMRC Clinical Trails Centre, University of Sydney, Australia. Electronic address: liz.barnes@ctc.usyd.edu.au.
authors: Elizabeth H
authors: EH
authors: Barnes
authors: TY Nelson Department of Neurology and Neurosurgery, The Children's Hospital at Westmead, Sydney, Australia. Electronic address: deepak.gill@health.nsw.gov.au.
authors: Deepak
authors: D
authors: Gill
authors: Neuroimmunology Group, Institute of Neuroscience and Muscle Research at The Kids Research Institute, The Children's Hospital at Westmead, University of Sydney, Australia; TY Nelson Department of Neurology and Neurosurgery, The Children's Hospital at Westmead, Sydney, Australia. Electronic address: russell.dale@health.nsw.gov.au.
authors: Russell C
authors: RC
authors: Dale
mesh_terms: D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D004569:Electroencephalography; D004660:Encephalitis / Q000175:diagnosis* / Q000209:etiology / Q000503:physiopathology; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male
keywords: Autoimmune; DRE; EEG; Encephalitis; FIRES; Herpes; NMDAR