Polymicrobial bacteremia.

Of 26,961 blood cultures taken during an 18-month period at the Cincinnati General Hospital, 1,715 (6%) were positive. Ninety-four patients had blood cultures containing more than one organism. Although aerobic and anaerobic streptococci were the most frequently isolated bacteria, a variety of microorganisms, including Staphylococcus aureus and the Klebsiella-Enterobacter-Serratia group, was isolated in different combinations depending on the underlying disease. Neurological illness, malignant neoplasms, burns, and decubitus ulcers were among the most common underlying conditions found. The overall mortality was 54%, but only 58% of these deaths were specifically related to an episode of polymicrobial bacteremia. Patient survival was significantly related to appropriate antimicrobial therapy.