Etiological associations and outcome predictors of acute electroencephalography in childhood encephalitis

Shekeeb S Mohammad; Samantha M Soe; Sekhar C Pillai; Margherita Nosadini; Elizabeth H Barnes; Deepak Gill; Russell C Dale

doi:10.1016/j.clinph.2016.07.014

Etiological associations and outcome predictors of acute electroencephalography in childhood encephalitis

Clin Neurophysiol. 2016 Oct;127(10):3217-24. doi: 10.1016/j.clinph.2016.07.014. Epub 2016 Aug 1.

Authors

Shekeeb S Mohammad¹, Samantha M Soe², Sekhar C Pillai³, Margherita Nosadini⁴, Elizabeth H Barnes⁵, Deepak Gill⁶, Russell C Dale⁷

Affiliations

¹ 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: [email protected].
² TY Nelson Department of Neurology and Neurosurgery, The Children's Hospital at Westmead, Sydney, Australia. Electronic address: [email protected].
³ 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: [email protected].
⁴ 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: [email protected].
⁵ NHMRC Clinical Trails Centre, University of Sydney, Australia. Electronic address: [email protected].
⁶ TY Nelson Department of Neurology and Neurosurgery, The Children's Hospital at Westmead, Sydney, Australia. Electronic address: [email protected].
⁷ 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: [email protected].

PMID: 27521622
DOI: 10.1016/j.clinph.2016.07.014

Abstract

Objectives: To examine EEG features in a retrospective 13-year cohort of children with encephalitis.

Methods: 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.

Results: 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).

Conclusions: 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.

Significance: EEG is a sensitive but non-discriminatory marker of childhood encephalitis. We highlight the EEG features that predict abnormal outcome and DRE.

Keywords: Autoimmune; DRE; EEG; Encephalitis; FIRES; Herpes; NMDAR.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Adolescent
Child
Child, Preschool
Electroencephalography*
Encephalitis / diagnosis*
Encephalitis / etiology
Encephalitis / physiopathology
Female
Humans
Infant
Male