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Last reviewed: 23 Jun 2024
Last updated: 23 May 2023

Summary

Definition

History and exam

Key diagnostic factors

  • presence of risk factors
  • male sex
  • age <30 years
  • meningismus
  • headache
  • cranial nerve palsy
  • positive Kernig or Brudzinski sign
  • fever
  • increased head circumference (infants)
  • bulging fontanelles (infants)
Full details

Other diagnostic factors

  • neurological deficit
  • papilloedema
Full details

Risk factors

  • sinusitis
  • otitis media
  • dental procedure/infection
  • meningitis
  • recent head and neck surgery or neurosurgery
  • congenital heart disease
  • endocarditis
  • diverticular disease
  • hereditary haemorrhagic telangiectasia or arteriovenous malformation
  • diabetes mellitus
  • HIV or immunocompromise
  • intravenous drug use
  • chronic granulomatous disease
  • haemodialysis
  • birth prematurity
  • cystic fibrosis
Full details

Diagnostic investigations

1st investigations to order

  • FBC
  • serum erythrocyte sedimentation rate (ESR)
  • serum CRP
  • serum PT, PTT, and INR
  • blood culture
  • MRI with contrast
  • CT head with and without contrast
  • ultrasound head (infants)
Full details

Investigations to consider

  • serum toxoplasma titre
  • magnetic resonance spectroscopy (MRS)
  • lumbar puncture (LP) with cerebrospinal fluid (CSF) analysis
  • CT chest, abdomen, and pelvis
  • bone scan
  • mammogram
Full details

Treatment algorithm

INITIAL

presumed brain abscess

ACUTE

suspected or confirmed bacterial aetiology

confirmed fungal aetiology

suspected or confirmed parasitic aetiology

cryptogenic brain abscess

Contributors

Authors

Walter A. Hall, MD, MBA

Professor

Department of Neurosurgery

SUNY Upstate Medical University

Syracuse

NY

Disclosures

WAH is an author of a number of references cited in this topic.

Acknowledgements

Dr Walter A. Hall would like to gratefully acknowledge Dr Peter D. Kim, a previous contributor to this topic. PDK declares that he has no competing interests.

Peer reviewers

Stephen Haines, MD

Professor and Head

Department of Neurosurgery

University of Minnesota

Minneapolis

MN

Disclosures

SH and WAH were colleagues on a faculty of the University of Minnesota between 1991 and 1997 and again between 2004 and 2006. They have coauthored articles on neurosurgical infection.

Sabrina Ravaglia, MD, PhD

Staff Physician

Department of Neurological Sciences

Institute of Neurology C. Mondino

Pavia

Italy

Disclosures

SR declares that she has no competing interests.

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