Cerebral abscesses are caused usually by bacteraemia or septicaemia. They are seen in patients in which sepsis often occurs, e.g. bronchiectasis, bacterial endocarditis. They may also arise due to a local infective focus, e.g. chronic mastoiditis, infected skull fracture.

Cerebral abscesses are space occupying lesions of the brain, apart from producing signs and symptoms of sepsis. They usually contian mixed aerobic and anaerobic organisms. The abscess contains tissue debris but is surrounded by a thickened membrane often consisting of fibroblasts.

Cerebral abscesses are difficult to treat and have high morbidity and mortality rates.