European survey of vancomycin-resistant enterococci in at-risk hospital wards and in vitro susceptibility testing of ramoplanin against these isolates

Abstract

A survey in eight European countries, including 13 hospitals, of vancomycin-resistant enterococci (VRE) in at-risk hospital wards (such as the ICU and the haematology ward) was performed in 2001, and the in vitro susceptibility of the isolates ramoplanin and other drugs was tested. A total of 1314 non-duplicate clinical enterococcal isolates were collected, and 38 (2.9%) were vancomycin resistant: 27 Enterococcus faecium and 11 Enterococcus faecalis ; 35 VanA and three VanB phenotypes. Rates of VRE among clinical enterococcal isolates varied between 0 and 1.7% for the participating countries, except the UK (10.4%) and Italy (19.6%). One hundred and twenty-three (3.5%) VRE were found among 3499 stool samples tested for the presence of these organisms: 111 (3.2%) E. faecium and 12 (0.3%) E. faecalis ; 114 (3.3%) VanA and nine (0.3%) VanB phenotypes. Rates of intestinal colonization with VRE varied between 0 and 1.2% for the participating countries, except Italy (7.5%) and the UK (32.6%). In vitro susceptibility testing showed that the Italian and UK VRE are multi-resistant (including resistance to ampicillin and high-level resistance to gentamicin and streptomycin), and that ramoplanin was active against all strains of VRE, with an MIC ₉₀ of 0.5 mg/L for clinical isolates. Pulsed-field gel electrophoresis showed that the high prevalence of VRE in the Italian and UK centres was related to the monoclonal emergence and spread of three centre-specific clones. This survey suggests that in some centres in Europe, a similar situation may be encountered to that in the USA (monoclonal spread of multi-resistant VRE in at-risk wards).