Brain abscesses may result from a number of causes including, extension of sepsis from middle ear or sinuses, trauma or surgery to the scalp, penetrating head injuries and embolic events from endocarditis

The presenting symptoms will depend upon the site of the abscess (those in critical areas e.g. motor cortex) will present earlier. Abscesses have a considerable mass effect in the brain and raised intracranial pressure is common.

• headache
  • often dull, persistent
• fever
  • may be absent and usually not the swinging pyrexia seen with abscesses at other sites
• focal neurology
  • e.g. oculomotor nerve palsy or abducens nerve palsy secondary to raised intracranial pressure
• other features consistent with raised intracranial pressure
  • nausea
  • papilloedema
  • seizures

Investigations

• Assessment of the patient includes imaging with CT scanning

MRI brain showing ring-enhancing lesion in the right frontal lobe with surrounding oedema. - e Image used on license from Radiopaedia

Management

• surgery
  • a craniotomy is performed and the abscess cavity debrided
  • the abscess may reform because the head is closed following abscess drainage.
• IV antibiotics: IV 3rd-generation cephalosporin + metronidazole
• intracranial pressure management: e.g. dexamethasone

Brain Abscess

Etiology:

can spread from contiguous infection in the sinuses, mastoid air cells, or otitis media

Organisms: