Application of molecular techniques to the study of nosocomial infections caused by enterococci.

Enterococci are components of the normal bowel flora of humans and other animals, and have traditionally been considered to be of relatively low virulence in healthy individuals. However, they are increasingly important nosocomial pathogens and have been cited as the leading organism isolated from hospital-acquired infections, and the third leading cause of nosocomial bacteremia in the United States in a recent National Nosocomial Infection Surveillance (NNIS) system report of the Centers for Disease Control (1). The increase in enterococcal infections has been associated with the emergence of resistance to multiple antibiotics, in particular resistance to B-lactams, high-level aminoglycoside resistance, and resistance to glycopeptides. Concern that antibiotic resistance will continue to spread and will increasingly render conventional antimicrobial chemotherapy inadequate for serious enterococcal infections has stimulated interest in methods to improve the diagnosis and epi-demiologic investigation of infections caused by enterococci.