Lung abscess: analysis of 66 cases from 1979 to 1991.

Sixty-six patients with bacterial lung abscess were treated between 1979 and 1991 in our hospital. Among these patients, death occurred in one of the 42 cases of community-acquired infection (mortality rate: 2.4%) and in 16 of the 24 cases of nosocomial infection (mortality rate: 66.7%). Of all 66 cases, 55 were culture-positive, and the etiologic agents isolated from 24 of the culture-positive cases were found to be anaerobic bacteria. The most common aerobes isolated from the foci were identified as Staphylococcus aureus, Klebsiella spp. and Pseudomonas aeruginosa, while the most common anaerobes were Bacteroides spp., Peptostreptococcus, Fusobacterium spp., microaerophilic Streptococcus and Veillonella. The mortality was higher in the cases with P. aeruginosa, Klebsiella spp. and Candida spp. than in those with other bacteria. The prognosis of lung abscess patients proved to depend on the presence of underlying diseases and on superinfection with aerobes.