title: Vancomycin-resistant Enterococcus faecium: catheter colonization, esp gene, and decreased susceptibility to antibiotics in biofilm.
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.
authors.affiliation: Department of Infectious Diseases, Infection Control and Employee Health (Unit 402), The University of Texas M. D. Anderson Cancer Center, P.O. Box 301402, Houston, Texas 77230-1402, USA. iraad@mdanderson.org
authors.forename: Issam I
authors.initials: II
authors.lastname: Raad
authors.forename: Hend A
authors.initials: HA
authors.lastname: Hanna
authors.forename: Maha
authors.initials: M
authors.lastname: Boktour
authors.forename: Gassan
authors.initials: G
authors.lastname: Chaiban
authors.forename: Ray Y
authors.initials: RY
authors.lastname: Hachem
authors.forename: Tanya
authors.initials: T
authors.lastname: Dvorak
authors.forename: Russell
authors.initials: R
authors.lastname: Lewis
authors.forename: Barbara E
authors.initials: BE
authors.lastname: Murray
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology* / Q000627:therapeutic use; D016470:Bacteremia / Q000188:drug therapy / Q000382:microbiology*; D001426:Bacterial Proteins / Q000502:physiology*; D018441:Biofilms / Q000254:growth & development; D002404:Catheterization / Q000009:adverse effects*; D016984:Enterococcus faecium / Q000187:drug effects* / Q000235:genetics / Q000472:pathogenicity; D041981:Gastrointestinal Tract / Q000382:microbiology; D006801:Humans; D008565:Membrane Proteins / Q000502:physiology*; D008826:Microbial Sensitivity Tests; D020713:Vancomycin Resistance / Q000502:physiology*
chemical_list: D000900:Anti-Bacterial Agents; D001426:Bacterial Proteins; D008565:Membrane Proteins; C116707:enterococcal surface protein, esp