Ecological replacement of Enterococcus faecalis by multiresistant clonal complex 17 Enterococcus faecium


Corresponding author and reprint requests: J. Top, Eijkman-Winkler Institute for Microbiology, Infectious Diseases and Inflammation, University Medical Centre Utrecht (UMC), G04.614, PO Box 85500, 3508 GA Utrecht, The Netherlands


The proportion of enterococcal infections caused by ampicillin-resistant Enterococcus faecium (AREfm) in a European hospital increased from 2% in 1994 to 32% in 2005, with prevalence rates of AREfm endemicity of up to 35% in at least six hospital wards. Diabetes mellitus, three or more admissions in the preceding year, and use of β-lactams and fluoroquinolones, were all associated with AREfm colonisation. Of 217 AREfm isolates that were genotyped, 97% belonged to clonal complex 17 (CC17). This ecological change mimics events preceding the emergence of vancomycin-resistant E. faecium (VREF) in the USA and may presage the emergence of CC17 VREF in European hospitals.