Brain Abscess Flashcards
What is a brain abscess?
Intracerebral collection of pus
Where do brain abscesses normally originate from?
1) Contiguous spread from:
- sinusitis
- otitis media
- dental infections
2) Haematogenous (distant) spread from:
- endocarditis
- pulmonary infections
3) Direct inoculation from trauma or neurosurgical procedures.
Define contiguous spread
Spread from something touching or close by
What are some risk factors for a brain abscess?
- immunocompromised
- congenital heart disease (R to L shunts)
- chronic otitis
- chronic sinusitis
- IVDU
What are 3 classical symptoms often associated with brain abscess?
1) Headache
2) Focal neuro deficits e.g. hemiparesis, aphasia or dysarthria, visual field defects
3) Fever
Also non-specific symptoms eg. seizures
Maybe symptoms of raised ICP if big abscess
Describe headache in brain abscess
Dull, constant, and progressively worsening.
Often localised to the site of the abscess.
What is the headache due to in a brain abscess?
Increased intracranial pressure or irritation of the meninges
Signs of raised ICP may also be present, especially in cases of large abscesses.
What are some signs of raised ICP?
- N&v
- altered consciousness
- papilloedema
Investigations in brain abscess?
MRI w/ gadolinium contrast –> superior in detecting early cerebritis.
CT –> useful for detecting complications like hydrocephalus and brain herniation.
What investigation is contraindicated in a brain abscess? Why?
LP –> due to risk of brain herniation
Mx of a brain abscess?
1) surgery
2) IV Abx
3) ICP mx e.g. dexamethasone
What surgery is indicated in a brain abscss?
A craniotomy is performed and the abscess cavity debrided.
Note - the abscess may reform because the head is closed following abscess drainage.
What Abx are indicated in a brain abscess?
IV 3rd-generation cephalosporin + metronidazole
