Changes in the prevalence of vancomycin-resistant enterococci in response to antimicrobial formulary interventions: Impact of progressive restrictions on use of vancomycin and third-generation cephalosporins

Abstract

This study sought to assess the impact of restricting use of vancomycin and third-generation cephalosporins on vancomycin-resistant enterococci (VRE) prevalence. All clinical enterococcal isolates identified at a large academic medical center during a 10-year period were analyzed. Changes in VRE prevalence after sequential restrictions on use of vancomycin and third-generation cephalosporins were evaluated. The correlation between antibiotic use and VRE prevalence was also investigated. Vancomycin use initially decreased by 23.9% but returned to preintervention levels by the end of the study. Third-generation cephalosporin use decreased by 85.8%. However, VRE prevalence increased steadily from 17.4% to 29.6% during the 10-year period (P