This Article Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Reprints and Permissions Copyright Information Books from ASM Press MicrobeWorld Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Naas, T. Articles by Nordmann, P. Search for Related Content PubMed PubMed Citation Articles by Naas, T. Articles by Nordmann, P.

 Previous Article  |  Next Article 

Journal of Clinical Microbiology, August 2005, p. 3642-3649, Vol. 43, No. 8
0095-1137/05/$08.00+0     doi:10.1128/JCM.43.8.3642-3649.2005
Copyright © 2005, American Society for Microbiology. All Rights Reserved.

First Nosocomial Outbreak of Vancomycin-Resistant Enterococcus faecium Expressing a VanD-Like Phenotype Associated with a vanA Genotype

Service de Bactériologie-Virologie,¹ Service de Nephrologie, Hôpital de Bicêtre, Assistance Publique-Hôpitaux de Paris, Faculté de Médecine Paris-Sud, Université Paris XI, 94275, K.-Bicêtre, France²

Received 15 February 2005/ Returned for modification 29 March 2005/ Accepted 9 April 2005

Although enterococci expressing acquired vancomycin resistance phenotype have been reported increasingly worldwide, they have been rarely reported in France. From August to December 2004 we faced an outbreak of vancomycin-resistant Enterococcus faecium (VRE) isolates in the nephrology department at Bicêtre Hospital (K.-Bicêtre, France). The expression of the glycopeptide resistance varied among the 26 VRE isolates, with vancomycin MICs ranging from 12 to >256 µg/ml, whereas teicoplanin MICs ranged from 4 to 48 µg/ml. However, several strains appeared to be susceptible to glycopeptides according to disk diffusion testing and expressed resistance only after subculture with glycopeptides. In addition, a heterogeneous expression of glycopeptide resistance was also observed. This so-called VanD-like phenotype of resistance (low-level resistance to vancomycin and mostly susceptibility to teicoplanin) was surprisingly associated with a vanA gene. Plasmid extraction and mating-out experiments indicated that the vanA gene was located on a 200-kb self-transferable plasmid. Pulsed-field gel electrophoresis identified mostly dissemination of a single clone, whereas diffusion of the VanA-positive plasmid in different genomic backgrounds had also occurred. The vanA gene was part of a vanA-type operon for expression of resistance located on a Tn1546-like transposon. Sequencing of this transposon identified insertion of insertion sequence IS16 in the vanY gene that encodes a D,D-carboxypeptidase that might explain in part the peculiar VanD-type phenotype of resistance. This report is the first description of a VRE outbreak in France and underlines the difficulty in detecting this organism due to variability on the expression of the glycopeptide resistance trait, if any.

This article has been cited by other articles:

• Cuzon, G., Naas, T., Fortineau, N., Nordmann, P. (2008). Novel Chromogenic Medium for Detection of Vancomycin-Resistant Enterococcus faecium and Enterococcus faecalis. J. Clin. Microbiol. 46: 2442-2444 [Abstract] [Full Text]  
• Ergani-Ozcan, A., Naas, T., Baysan, B. O., Ogunc, D., Inan, D., Colak, D., Nordmann, P. (2008). Nosocomial outbreak of vancomycin-resistant Enterococcus faecium in a paediatric unit at a Turkish university hospital. J Antimicrob Chemother 61: 1033-1039 [Abstract] [Full Text]  
• Song, J.-H., Ko, K. S., Suh, J. Y., Oh, W. S., Kang, C.-I., Chung, D. R., Peck, K. R., Lee, N. Y., Lee, W. G. (2008). Clinical implications of vancomycin-resistant Enterococcus faecium (VRE) with VanD phenotype and vanA genotype. J Antimicrob Chemother 61: 838-844 [Abstract] [Full Text]  
• Deplano, A., Denis, O., Nonhoff, C., Rost, F., Byl, B., Jacobs, F., Vankerckhoven, V., Goossens, H., Struelens, M. J. (2007). Outbreak of hospital-adapted clonal complex-17 vancomycin-resistant Enterococcus faecium strain in a haematology unit: role of rapid typing for early control. J Antimicrob Chemother 60: 849-854 [Abstract] [Full Text]  
• Delmas, J., Robin, F., Schweitzer, C., Lesens, O., Bonnet, R. (2007). Evaluation of a New Chromogenic Medium, chromID VRE, for Detection of Vancomycin-Resistant Enterococci in Stool Samples and Rectal Swabs. J. Clin. Microbiol. 45: 2731-2733 [Abstract] [Full Text]  
• Bellais, S., Arthur, M., Dubost, L., Hugonnet, J.-E., Gutmann, L., van Heijenoort, J., Legrand, R., Brouard, J.-P., Rice, L., Mainardi, J.-L. (2006). Aslfm, the D-Aspartate Ligase Responsible for the Addition of D-Aspartic Acid onto the Peptidoglycan Precursor of Enterococcus faecium. J. Biol. Chem. 281: 11586-11594 [Abstract] [Full Text]