In this case bacteria are carried to the site of abscess from a distant source, typically the skin, lungs, mouth, or heart valves. Under these circumstances there is not a solitary abscess but rather multiple abscesses in the brain. Lastly, a brain abscess can result from head trauma. An infection can arise from a wound penetrating the skull. In this case inoculation with bacteria occurs from infected bone fragments or debris from the penetrating instrument.
Symptoms resulting from a brain abscess depend on the size and the location of the infection.
Generally, the prognosis associated with brain abscess is dependent on the rapidity and efficacy of treatment, the age and medical condition of the patient, and the size and location of the abscess. This drop in mortality is also due to improved treatment methods, including intensive care. The probability that a patient will respond to such treatment is directly dependent on his or her alertness. Patients who are awake and responsive usually do well, whereas those patients in prolonged coma have a poorer prognosis. As mentioned, brain imaging is central to the diagnosis of brain abscess and thus essential to the early detection of such an infection.