Brain Abscess - Infections of the CNS

Brain Abscess

·        Aetiology:

o   Chronic otitis media, sinusitis or dental sepsis

o   Trauma: foreign body, skull fracture, CNS surgery 

o   Haematogenous spread (may be multiple abscess) from congenital heart disease (with R-L shunt), bronchiectasis, abdominal abscess, endocarditis, etc

·        Bacteria:

o   Temporal lobe (from chronic otitis media):

§  Anaerobes: Bacteroides fragilis

§  Aerobes: Proteus mirabilis + HIB and E faecalis

o   Frontal lobe (from chronic sinusitis)

§  Anaerobes: Bacteroides melaninogenicus

§  Aerobes: Strep milleri

o   Traumatic: Staph aureus

o   Haematogenous spread: Staph aureus, Viridians Strep, Bacteroides fragilis, etc

·        Treatment:

o   Surgery

o   Antibiotics:

§  Anaerobes: Metronidazole

§  Aerobes:

·        Strep: Amoxycillin

·        Coliforms: Cefotaxime

·        Staph aureus: Flucloxacillin