Penetration of brain abscess by systemically administered antibiotics

Abstract

✓ In six consecutive patients treated with systemic antibiotics for brain abscess, chloramphenicol, methicillin, and penicillin were found capable of penetrating the abscess in therapeutic concentration. Nafcillin, a fourth antibiotic tested, failed to penetrate. While on antibiotics, all six patients continued to deteriorate neurologically until needle aspiration of the abscess was carried out, after which recovery began promptly. Organisms were found in the pus despite the presence of therapeutically effective antibiotic levels, and despite the fact that the organisms were sensitive, in vitro, to the antibiotics used. These observations confirm that antibiotics alone are insufficient and that surgical evacuation of the abscess is essential. The need for local instillation of antibiotics directly into abscesses is questionable since penetration following systemic administration of three antibiotics tested was adequate when blood levels were high. It is suggested that the instillation of penicillin or its derivatives be avoided in view of their potential epileptogenicity as well as the questionable value of this method.