, Volume 39, Issue 2, pp 127–133 | Cite as

Molecular epidemiology of Enterococcus faecium isolates from an Italian hospital

  • L. Fallico
  • C. Boldrin
  • A. Grossato
  • E. Franchin
  • E. De Canale
  • T. Tommasini
  • S. G. Parisi
  • R. Manganelli
  • G. Palù
Clinical and Epidemiological Study



Outbreaks of vancomycin-resistant Enterococcus faecium (VRE) strains is an emerging problem worldwide. Even if still relatively uncommon in European hospitals, infections caused by VRE have also been increasing recently in this continent.


In this study, we characterized 50 consecutive VRE and 23 vancomycin-sensitive E. faecium (VSE) isolates collected in an Italian hospital. The presence of the esp gene and that of genes encoding resistance to glycopeptides was investigated by polymerase chain reaction (PCR). All of the isolates were typed by multi-locus sequence typing (MLST), and a selection of them also by pulsed-field gel electrophoresis (PFGE).


We found that all of the VRE and 18 (78%) of the VSE strains belonged to the single clonal complex-17 (CC17). The most represented sequence type (ST) was ST78 (34% of the isolates). When further analyzed by PFGE, ST78 isolates were subdivided into five pulsotypes, four of them closely related. The strong association between the esp gene and CC17 was confirmed. Interestingly, such an association was higher among vancomycin-resistant isolates. Most of the esp-positive isolates (34/46, 74%) encoded Esp4, a rare variant of this protein characterized by the absence of A repeats.


Our findings underscore the role of the CC17 lineage in the nosocomial spread of VRE and VSE, and its rapid local evolution, underscoring the need for programs designed to provide early detection in order to prevent its spreading among the nosocomial population.


Enterococcus faecium VRE Esp MLST PFGE Vancomycin Hospital infection 



The authors wish to thank Rob J.L. Willems and Janetta Top for the helpful discussion. This work was supported by the Veneto Region.

Conflict of interest



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Copyright information

© Urban & Vogel 2011

Authors and Affiliations

  • L. Fallico
    • 1
  • C. Boldrin
    • 1
  • A. Grossato
    • 2
  • E. Franchin
    • 1
    • 2
  • E. De Canale
    • 1
  • T. Tommasini
    • 1
  • S. G. Parisi
    • 1
    • 2
  • R. Manganelli
    • 1
    • 2
  • G. Palù
    • 1
    • 2
  1. 1.Regional Reference Centre for Infectious Diseases, Microbiology and Virology UnitAzienda Ospedaliera di PadovaPadovaItaly
  2. 2.Department of Histology, Microbiology and Medical BiotechnologiesUniversity of PadovaPadovaItaly

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