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Viral meningitis

Last reviewed: 23 Jun 2024
Last updated: 16 Nov 2022

Summary

Definition

History and exam

Key diagnostic factors

  • headache
  • nausea and vomiting
  • photophobia
  • neck stiffness
  • fever
Full details

Other diagnostic factors

  • rash
  • Kernig sign
  • Brudzinski sign
Full details

Risk factors

  • infants and young children
  • young adults
  • older people
  • summer and fall
  • exposure to mosquito or tick vector
  • unvaccinated for mumps
  • use of swimming pools and ponds
  • immunosuppression
  • exposure to rodents
Full details

Diagnostic tests

1st tests to order

  • CSF microscopy
  • CSF Gram stain
  • CSF bacterial culture
  • CSF protein
  • CSF glucose
  • CSF PCR for enteroviruses
  • CSF PCR for herpes viruses
  • HIV serology/HIV reverse transcriptase (RT)-PCR
Full details

Tests to consider

  • CT/MRI head
  • EEG
  • CSF viral culture
Full details

Emerging tests

  • CSF C-reactive protein (CRP)
  • serum and CSF procalcitonin
  • CSF lactate

Treatment algorithm

INITIAL

possible bacterial meningitis

ACUTE

confirmed viral agent, other than HSV, varicella zoster, or CMV

HSV or varicella zoster confirmed causative agent

CMV confirmed causative agent

ONGOING

recurrent viral meningitis

Contributors

Authors

John Williams, MRCP, DTM&H
John Williams

Consultant

The James Cook University Hospital

Middlesbrough

UK

Disclosures

JW declares that he has no competing interests.

Acknowledgements

Dr John Williams would like to gratefully acknowledge Dr David Chadwick, a previous contributor to this topic. DC is an author of a reference cited in this topic.

Peer reviewers

Karen Roos, MD

John and Nancy Nelson Professor of Neurology

Indiana University School of Medicine

Indianapolis

IN

Disclosures

KR declares that she has no competing interests.

Vassiliki Syriopoulou, MD

Professor of Pediatrics

University of Athens

Aghia Sophia Children's Hospital

Athens

Greece

Disclosures

VS declares that she has no competing interests.

  • Differentials

    • Meningitis, bacterial
    • Encephalitis
    • Encephalopathy (toxic/metabolic)
    More Differentials
  • Guidelines

    • A guide to utilization of the microbiology laboratory for diagnosis of infectious diseases: 2018 update by the Infectious Diseases Society of America and the American Society for Microbiology
    • The UK joint specialist societies guideline on the diagnosis and management of acute meningitis and meningococcal sepsis in immunocompetent adults
    More Guidelines
  • Patient information

    Meningitis and septicemia

    Lumbar puncture

    More Patient information
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