145-151 Supp A-25

The rapid emergence of strains of Enterococcus faecium with high-level resistance to vancomycin (VREF) has created a serious therapeutic void in the management of enterococcal infection. As for vancomycin-susceptible enterococci, serious infection with VREF strains frequently occurs in debilitated or immunocompromised hosts with significant underlying disease. Several recent series report an increase in the attributable morbidity and mortality due to vancomycin-resistant enterococcal infection in both medical and surgical patients. At present there are no antimicrobial agents with proven in-vivo efficacy for serious VREF infection. Several investigators have reported the use of approved antimicrobial agents including novobiocin, chloramphenicol or triple combination therapy with ampicillin, vancomycin and gentamicin. However, these trials included only a small number of patients, lacked any control data, and have not been confirmed by others. Teicoplanin may be effective against vancomycin-resistant enterococci with the VanB phenotype but the development of resistance during therapy may severely limit the efficacy of this agent. Quinupristin/dalfopristin (RP 59500) is a novel investigational antibiotic which belongs to the streptogramin family. It has a wide spectrum of activity against Grampositive bacteria including coagulase-negative staphylococci, Staphylococcus aureus (including methicillinresistant strains) and Streptococcus pneumoniae. Quinupristin/dalfopristin was previously reported to be successful in the treatment of VREF peritonitis in patients on peritoneal dialysis but clinical experience remains very