Vancomycin-resistant Enterococcus faecium: catheter colonization, esp gene, and decreased susceptibility to antibiotics in biofilm

Antimicrob Agents Chemother. 2005 Dec;49(12):5046-50. doi: 10.1128/AAC.49.12.5046-5050.2005.

Abstract

To evaluate the molecular characteristics and antibiotic susceptibility in biofilm of vancomycin-resistant Enterococcus faecium (VREF) organisms that had caused catheter-related VREF bacteremia (VREF-CRB), we compared 22 isolates causing bacteremia obtained from patients with VREF-CRB with 30 isolates from control patients with gastrointestinal colonization by VREF. Using pulsed-field gel electrophoresis, we identified 17 unique strains among the 22 VREF-CRB isolates and 23 strains among the gastrointestinal isolates. The esp gene was detected in 53% (9 of 17) of the VREF-CRB and 61% (14 of 23) of the control strains (P = 0.6). VREF-CRB produced heavier biofilm colonization of silicone disks than did control organisms (P < 0.001). Daptomycin, minocycline, and quinupristin-dalfopristin were each independently more active than linezolid in reducing biofilm colonization by VREF-CRB (P < 0.01), with daptomycin being the most active, followed by minocycline. In conclusion, the esp gene in VREF is not associated with heavy biofilm colonization or catheter-related bacteremia. In biofilm, daptomycin and minocycline were the most active antibiotics against VREF, and linezolid was the least active.

MeSH terms

  • Anti-Bacterial Agents / pharmacology*
  • Anti-Bacterial Agents / therapeutic use
  • Bacteremia / drug therapy
  • Bacteremia / microbiology*
  • Bacterial Proteins / physiology*
  • Biofilms / growth & development
  • Catheterization / adverse effects*
  • Enterococcus faecium / drug effects*
  • Enterococcus faecium / genetics
  • Enterococcus faecium / pathogenicity
  • Gastrointestinal Tract / microbiology
  • Humans
  • Membrane Proteins / physiology*
  • Microbial Sensitivity Tests
  • Vancomycin Resistance / physiology*

Substances

  • Anti-Bacterial Agents
  • Bacterial Proteins
  • Membrane Proteins
  • enterococcal surface protein, esp