Emergence of Clonal Complex 17 Enterococcus faecium in The Netherlands

Abstract

The global emergence of vancomycin-resistant Enterococcus faecium has been characterized as the clonal spread of clonal complex 17 (CC17) E. faecium. CC17 was defined upon multilocus sequence typing and is characterized by resistance to quinolones and ampicillin and the presence of the enterococcal surface protein (Esp) in the majority of isolates. The recently noticed increased incidence of vancomycin-susceptible CC17 E. faecium infections in our hospital initiated a nationwide study to determine ecological changes among enterococcal infections. The data and strain collections were obtained from 26 (38%) and 9 (14%) of 66 microbiology laboratories in The Netherlands. E. faecium and E. faecalis were distinguished by multiplex PCR; all E. faecium isolates were genotyped by multiple-locus variable-number tandem-repeat analysis (MLVA), and the presence of esp was identified by PCR. Average numbers of ampicillin-resistant enterococcal isolates from normally sterile body sites per hospital increased from 5 ؎ 1 in 1994 to 25 ؎ 21 in 2005. Among all enterococcal bloodstream infections, the proportions of ampicillin-resistant E. faecium (AREF) increased from 4% in 1994 to 20% in 2005 (P < 0.001). All E. faecalis isolates were susceptible to ampicillin, whereas 78% of the E. faecium isolates were resistant (49% of these contained esp). Genotyping revealed that 86% of AREF isolates belonged to CC17, including four dominant MLVA types found in >3 hospitals, accounting for 64% of the AREF isolates. Infections caused by CC17 E. faecium has increased nationwide, especially in university hospitals due to the clonal spread of four MLVA types, and seems associated with acquisition of the esp gene.The emergence of vancomycin-resistant Enterococcus faecium (VREF) in the United States in the 1990s was preceded by the emergence of ampicillin-resistant Enterococcus faecium (AREF) in the 1980s (8,11,27,28). Molecular epidemiological studies of human-and animal-derived E. faecium since then, revealed the existence of a genetic lineage, labeled clonal complex 17 (CC17), associated with nosocomial E. faecium outbreaks and infections in five continents. CC17 is characterized by ampicillin and quinolone resistance and the presence of a putative pathogenicity island, including the esp gene in the majority of isolates (2-4, 9, 12, 17-20, 31, 36). In retrospect, it seems likely that the acquisition of ampicillin resistance was an earlier step in hospital adaptation of E. faecium, facilitating the subsequent emergence of VREF (18,36).Since 2000, infection rates of VREF are rising in European hospitals (see EARSS Annual Report 2005 [www.rivm.nl /earss]), suggesting that the increase of VREF in Europe follows the American epidemiology with a 10-year delay. Little is known, though, about the molecular epidemiology of AREF.In our hospital (the University Medical Center Utrecht [UMCU]), the proportion of invasive enterococcal infections caused by AREF increased from 2% in 1994 to 32% in 2005, with partial replacement of ampicillin-susceptible (Amp ...

Screening municipal wastewater effluent and surface water used for drinking water production for the presence of ampicillin and vancomycin resistant enterococci

“…Applying ampicillin SBA, E. faecium was the only species observed in this study, which is in line with previous investigations by Anastasiou and Schmitt (2011), who found that a high percentage (88 -100%) of ARE present in surface water was AREfm. Considering that ARE have emerged in Europe as a frequent cause of invasive enterococcal infections even in countries with a low prevalence of VRE, such as the Netherlands (Top et al, 2007;Top et al, 2008b), the numbers of AREfm in WWTP effluent observed in this study indicate a reservoir of AREfm outside the healthcare setting. To confirm that the AREfm found in this study are hospitalassociated E. faecium (HA-Efm), additional analysis on the presence of enterococcal surface protein (esp) gene can provide additional information.…”

Current Trends of Emergence and Spread of Vancomycin-Resistant Enterococci

“…Certain European countries (Netherlands, Denmark, Spain) showed a wide prevalence of hospital-associated clonal types of E. faecium but vancomycin resistance rates are still low (Oteo et al, 2007;Lester et al, 2008;Top et al, 2008b;Valdezate et al, 2009;Lester et al, 2009). In other countries rates of VRE remain at a comparably high rate such as Ireland and Portugal 5 (Novais et al, 2008;Morris-Downes et al, 2010).…”

Antimicrobial Resistance and Multilocus Sequence Typing of Vancomycin-ResistantEnterococcus faeciumIsolated from the Chungcheong Area

“…Among those, clonal complex 17 (CC17) adapting to prolonged exposure to hospital setting is detected worldwide. The characteristics of CC17 are its resistance to ampicillin and quinolone, and variant esp gene as E. faecium pathogenicity island (PAI) [4,5]. It has been reported that the organisms isolated in Korea belong to CC17 [6,7].…”