Lung abscess and empyema.

Forty-eight patients presenting with lung abscess or empyema were studied between 1976 and 1984. The clinical features, diagnostic techniques and management are discussed. Aerobes were cultured from specimens obtained in 37.5 per cent of cases, both aerobes and anaerobes in 54.2 per cent and anaerobes alone in only 8.3 per cent. Bacteroides fragilis was not isolated. Forty-two per cent of patients had previously received antibiotics, but fully sensitive organisms were grown from 17 of 20 specimens from this group. Forty-five per cent of aerobes and 17.8 per cent of anaerobes were resistant to penicillin. There were no specific clinical features which distinguished the patients with a lung abscess from those with an empyema, nor between those with an underlying abnormality and those in whom the infection arose in a previously normal lung. Lung abscesses should be treated medically with intensive physiotherapy and appropriate antibiotics; penicillin can no longer be considered the antibiotic of choice. If the cavity fails to drain satisfactorily, further investigations should be undertaken to exclude a tumour or other underlying abnormality.