Article Text

Download PDFPDF
Severe encephalitis: aetiology, management and outcomes over 10 years in a paediatric intensive care unit
  1. Giordano Palmas1,2,
  2. Trevor Duke2,3
  1. 1Department of Paediatrics, Meyer Children's Hospital IRCCS, Florence, Italy
  2. 2Royal Children's Hospital Paediatric Intensive Care Unit, Parkville, Victoria, Australia
  3. 3The University of Melbourne Department of Paediatrics, Parkville, Victoria, Australia
  1. Correspondence to Dr Giordano Palmas, Meyer Children's Hospital IRCCS, Firenze, 50139, Italy; giordano.palmas{at}


Objective To describe the characteristics, differential diagnoses, management and outcomes of severe encephalitis in children.

Design A 10-year retrospective cohort study in children admitted to a tertiary paediatric intensive care unit (PICU) with suspected encephalitis. One to 6 months’ follow-up data were compared between different categories.

Participants Patients from 0 to 17 years of age with acute encephalopathy and one or more of fever, seizure, focal neurological findings, cerebrospinal fluid abnormalities, EEG/neuroimaging consistent with encephalitis.

Main outcome measures Epidemiology, clinical features, outcomes and risk factor analysis.

Results 175 children with encephalitis required intensive care unit (ICU) admission over 10 years. The median age was 4.5 months (IQR 1.6–54.8). The leading cause was enterovirus (n=49, 28%), followed by parechovirus, influenza, herpes simplex virus (HSV), human herpesvirus-6 (HHV-6), Streptococcus pneumoniae, acute-disseminated encephalomyelitis and anti-N-methyl-D-aspartate-receptor-associated encephalitis. Immune-mediated encephalitis had higher prevalence in females, older age and longer duration of encephalopathy. Mechanical ventilation was required by 74 children (42%); haemodynamic support by 28 children (16%), 3 received extracorporeal membrane oxygenation (ECMO) support. Eleven patients died (case fatality rate 6.3%): five with HHV-6, two enterovirus, two influenza, one HSV, one human-metapneumovirus. At follow-up, 34 children had mild or moderate disability, and six severe disability. In a multivariable logistic regression model, three factors were associated with severe disability or death: age <2 years old (OR 8.2, CI 1.0 to 67.2), Herpesviridae aetiology (OR 14.5, CI 1.2 to 177.3) and length of intubation (OR 1.005, CI 1.00 to 1.01).

Conclusions Encephalitis has a varied aetiology and causes death or severe disability in 1 in every 10 children requiring intensive care.

  • Infectious Disease Medicine
  • Intensive Care Units
  • Neurology
  • Paediatrics

Data availability statement

All data relevant to the study are included in the article or uploaded as supplementary information.

Statistics from

Request Permissions

If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.

Data availability statement

All data relevant to the study are included in the article or uploaded as supplementary information.

View Full Text


  • Contributors All authors contributed equally to this work and are to be considered guarantors.

  • Funding The authors have not declared a specific grant for this research from any funding agency in the public, commercial or not-for-profit sectors.

  • Competing interests None declared.

  • Provenance and peer review Not commissioned; externally peer reviewed.

  • Supplemental material This content has been supplied by the author(s). It has not been vetted by BMJ Publishing Group Limited (BMJ) and may not have been peer-reviewed. Any opinions or recommendations discussed are solely those of the author(s) and are not endorsed by BMJ. BMJ disclaims all liability and responsibility arising from any reliance placed on the content. Where the content includes any translated material, BMJ does not warrant the accuracy and reliability of the translations (including but not limited to local regulations, clinical guidelines, terminology, drug names and drug dosages), and is not responsible for any error and/or omissions arising from translation and adaptation or otherwise.