Enterococcal infections in surgical patients: the mystery continues.

The frequency of isolation of enterococci from surgical patients has increased significantly during the past decade, although the role of these organisms as pathogens in mixed infections remains a mystery. Bacteremia and other infections in which enterococci are the only pathogens frequently result in high morbidity and mortality among patients unless specific antimicrobial therapy is initiated promptly. Debate continues concerning the necessity for treatment with such agents when this organism is isolated as a component of a polymicrobial infecting flora. Our recent data indicate that enterococci are rarely isolated in postoperative infections after penetrating abdominal trauma if no gastrointestinal perforation has occurred. However, they were found in 56% of postoperative infections of patients with gastrointestinal perforation. In contrast, enterococci were isolated in only 9% of cultures of specimens from patients with secondary suppurative peritonitis. The occurrence of superinfection after therapy with a cephalosporin appears to be an important factor in this finding. Future studies are necessary to evaluate the efficacy of antibiotic treatment of enterococcal infections and to assess the need for prophylaxis against enterococci.