Twenty-five percent of intra-cerebral abscesses occur in children either as a result of an otogenic focus or cyanotic congenital heart disease.
Streptococci are the commonest organisms, especially Strep. milleri, but anaerobes are also isolated in 50% of cases.
Fungal infections are most often seen in immunocompromised patients and these infections usually involve the candida species. HIV patients have a particularly high incidence of toxoplasmosis infections. In 20% of cases, the cause of the abscess is unknown.
Patients can present with indolent or fulminant symptoms. Fever may, or may not, be present.
The symptoms are due to the site and size of the abscess, but altered mental status and hemiplegia are common.
More information on intra-cerebral abscesses can be found in the session about intra-cranial infections.
Learning Bite
It is not possible to distinguish reliably between primary tumour, solitary metastasis and cerebral abscess on the basis of CT imaging alone.