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Last reviewed: 17 Mar 2025
Last updated: 11 Mar 2025

Summary

Definition

History and exam

Key diagnostic factors

  • rapid onset of illness and rapid deterioration
  • fever
  • leg pain
  • seizures
  • neck pain and stiffness
  • paresis
  • headache
  • photophobia
  • altered mental status
  • altered consciousness
  • focal neurological deficit including cranial nerve involvement and abnormal pupils
  • hypotension
  • shock
  • toxic/moribund state
  • pallor or mottled skin
  • rash
  • cold hands and feet
  • hypotonia
  • high-pitched cry
  • Kernig sign
  • Brudzinski sign
  • bulging fontanel

Other diagnostic factors

  • irritability
  • lethargy
  • muscle ache/joint pain
  • poor appetite or feeding
  • nausea or vomiting
  • thirst
  • coryza, sore throat, or cough
  • respiratory distress
  • tachycardia

Risk factors

  • young age
  • complement deficiency
  • use of eculizumab and ravulizumab
  • immunoglobulin deficiency
  • HIV infection
  • asplenia or hyposplenia
  • college attendance
  • close contact with invasive meningococcal infection
  • household crowding
  • travel to a hyperendemic or epidemic area
  • laboratory workers
  • tobacco smoke exposure
  • recent move into a new community
  • respiratory infection
  • visiting bars/clubs
  • kissing

Diagnostic tests

1st tests to order

  • blood cultures
  • CBC and differential
  • electrolytes, calcium, magnesium, phosphate, glucose
  • coagulation profile (prothrombin time, INR, activated PTT, fibrinogen, fibrin degradation products)

Tests to consider

  • cerebrospinal fluid (CSF) Gram stain
  • CSF cell count and differential
  • CSF glucose, protein
  • CSF culture
  • antigen detection in CSF
  • chest x-ray
  • CT head
  • Gram stain of non-CSF body fluid
  • culture of non-CSF body fluid
  • immunohistochemical staining of skin lesion biopsy
  • echocardiography
  • joint x-ray
  • polymerase chain reaction

Treatment algorithm

Contributors

Authors

Elisabeth Adderson, MD
Elisabeth Adderson

Associate Member

St. Jude Children's Research Hospital

Associate Professor of Pediatrics

University of Tennessee Health Sciences Center

Memphis

TN

Disclosures

EA declares that she has no competing interests.

Peer reviewers

Richard T. Ellison III, MD

Professor of Medicine, Microbiology & Physiological Systems

UMass Chan Medical School

Worcester

MA

Disclosures

RE declares that he has no competing interests.

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