title: High vancomycin resistance among biofilms produced by Staphylococcus species isolated from central venous catheters.
abstract: Biofilm production is an important mechanism that allows microbes to escape host defences and antimicrobial therapy. Vancomycin has been used largely for the treatment of methicillin-resistant staphylococcal infections. Here, we determined the minimal inhibitory concentration (MIC) and minimal biofilm eradication concentration (MBEC) for 82 Staphylococcus species isolated from central venous catheters (CVC). Our results showed that the 41 strong and moderate-biofilm-producing isolates presented a higher MBEC/MIC ratio for vancomycin than the 24 weak-biofilm-producing isolates, illustrating the importance of biofilm production ability and the difficulty in treating biofilm-related infections. The MBEC was significantly higher in moderate-biofilm-producing isolates than in weak-biofilm-producing isolates (p < 0.001) and in strong-biofilm-producing isolates than in weak-biofilm-producing isolates (p = 0.001). The correlation between the MIC and the MBEC was poor. Based on our results, we recommend that bacterial biofilms be suspected in all cases of CVC infection.
authors.affiliation: Faculdade de Farmácia, Universidade Federal do Rio Grande do Sul, Av. Ipiranga 2752, 90610-000, Porto Alegre, RS, Brasil. analucia2112@gmail.com
authors.forename: Ana Lúcia Souza
authors.initials: AL
authors.lastname: Antunes
authors.forename: Jéssica Weis
authors.initials: JW
authors.lastname: Bonfanti
authors.forename: Leandro Reus Rodrigues
authors.initials: LR
authors.lastname: Perez
authors.forename: Camille Cattani Ferreira
authors.initials: CC
authors.lastname: Pinto
authors.forename: Ana Lúcia Peixoto de
authors.initials: AL
authors.lastname: Freitas
authors.forename: Alexandre José
authors.initials: AJ
authors.lastname: Macedo
authors.forename: Afonso Luis
authors.initials: AL
authors.lastname: Barth
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D018441:Biofilms / Q000187:drug effects / Q000254:growth & development*; D002405:Catheterization, Central Venous / Q000295:instrumentation*; D002408:Catheters, Indwelling / Q000382:microbiology*; D006801:Humans; D008826:Microbial Sensitivity Tests; D013210:Staphylococcus / Q000145:classification / Q000187:drug effects* / Q000302:isolation & purification / Q000502:physiology; D020713:Vancomycin Resistance
chemical_list: D000900:Anti-Bacterial Agents