Multihospital surveillance of nosocomial methicillin-resistant Staphylococcus aureus, vancomycin-resistant enterococcus, and Clostridium difficile: analysis of a 4-year data-sharing project, 1999-2002.

Background This study sought to establish a benchmark of resistant organism rates among a cohort of regional hospitals. Methods The Centers for Disease Control and Prevention (CDC) definitions were used to standardize the methodology for obtaining rates per 1000 patient days of nosocomial infection and colonization with methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant enterococcus (VRE), and nosocomial infection with Clostridium difficile (CDIF). Only newly acquired nosocomial cases were counted. Data were reported as individual hospital control charts and as cohorted aggregate data. VHA East Coast Infection Control Professionals from 32 hospitals in New Jersey and Pennsylvania were involved. Results Benchmarks were established with pooled mean rates for each cohort. During the observational period, a statistically significant downward trend was observed for VRE and MRSA ( P = .02 and .0007, respectively), and an upward trend was observed for CDIF ( P = .0256). Conclusion Benchmarks were established to compare nosocomial MRSA, VRE, and CDIF rates. Although significant changes in rates were observed, no attempt was made to establish a causal relationship between infection control practices and observed rates. However, a secondary gain was achieved through sharing best practices.