These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


Pubmed for Handhelds

PUBMED FOR HANDHELDS

Search MEDLINE/PubMed

  • Title: In vitro analysis of resistance selection by linezolid in vancomycin-susceptible and -resistant Enterococcus faecalis and Enterococcus faecium.
    Author: Allen GP, Bierman BC.
    Journal: Int J Antimicrob Agents; 2009 Jul; 34(1):21-4. PubMed ID: 19243921.
    Abstract:
    The pharmacodynamics of resistance development to linezolid has not been extensively studied, especially when a large bacterial inoculum is exposed to this agent. We simulated the usual therapeutic dose of linezolid, 600 mg intravenously every 12h [estimated maximum concentration, area under the concentration-time curve (AUC) and half-life of 10.4 mg/L, 61.9 microg h/mL and 4.8h, respectively], in an in vitro pharmacodynamic model and investigated the applicability of the mutant selection window (MSW) to linezolid against vancomycin-susceptible and -resistant Enterococcus faecalis and Enterococcus faecium. Four strains were studied, including vancomycin-susceptible (ATCC 29212) and -resistant (ATCC 51299) E. faecalis and vancomycin-susceptible (GP33) and -resistant (GP32) E. faecium. The minimum inhibitory concentration (MIC) for all strains was 2mg/L; mutant prevention concentration (MPC) values were 4 mg/L for ATCC 29212 and GP33 and 8 mg/L for ATCC 51299 and GP32. Linezolid failed to achieve bactericidal action against ATCC 29212 and GP33 [AUC/MIC=30.95, AUC/MPC=15.48, %T(MSW) (% of the dosing interval that concentrations fall in the MSW)=40%] and ATCC 51299 and GP32 (AUC/MIC=30.95, AUC/MPC=7.74, %T(MSW)=80.1%). Linezolid-resistant subpopulations (MIC=8 mg/L) of all isolates were selected. Our data suggest that linezolid resistance in enterococci will continue to emerge upon continued use of this antimicrobial.
    [Abstract] [Full Text] [Related] [New Search]