The clinical importance of anaerobic bacteria in wound infections after gastrointestinal surgery.

Wound cultures from 54 patients with infections after gastrointestinal surgery were examined. Cultures from wounds after surgery on the upper gastrointestinal tract grew few organisms, mainly aerobic gram-positive cocci. Culture from wounds on the lower gastrointestinal tract grew strains of bacteria, aerobic and anaerobic gram-negative rods dominating. Indirect immunofluorescence studies on acute and convalescent phase sera showed significant immune response against Bacteroides fragilis in a majority of cases. Immune response against anaerobic cocci was seldom found. Very high antibody titres against Clostridium perfringens were often found, both in patients' and control sera.