Activity of linezolid and daptomycin against methicillin-resistant coagulase-negative staphylococci with increased MIC for vancomycin isolated from blood cultures in pediatric patients

J Chemother. 2014 Oct;26(5):273-5. doi: 10.1179/1973947813Y.0000000134. Epub 2013 Dec 6.

Abstract

We evaluated minimal inhibitory concentration (MIC) for vancomycin, daptomycin, and linezolid in methicillin-resistant coagulase-negative staphylococci (MR-CoNS). Minimal inhibitory concentration of 2-4 mg/l for vancomycin was observed in 16% of strains, and among them 19% had MIC at breakpoint for daptomycin or linezolid. Among strains completely susceptible to vancomycin, 16% had MIC at breakpoint for daptomycin and 11% had for linezolid. This large proportion of pathogens with MIC around the breakpoint suggests a possible risk of treatment failure with these drugs. This phenomenon is worth further and constant monitoring.

Keywords: Daptomycin,; Increased minimal inhibitory concentration,; Linezolid,; Methicillin-resistant coagulase-negative staphylococci,; Pediatric patients; Vancomycin,.

MeSH terms

  • Acetamides / pharmacology*
  • Anti-Bacterial Agents / pharmacology*
  • Child
  • Coagulase / metabolism
  • Daptomycin / pharmacology*
  • Dose-Response Relationship, Drug
  • Humans
  • Linezolid
  • Methicillin Resistance / drug effects*
  • Microbial Sensitivity Tests
  • Oxazolidinones / pharmacology*
  • Staphylococcus / drug effects*
  • Staphylococcus / metabolism
  • Staphylococcus / pathogenicity
  • Structure-Activity Relationship
  • Vancomycin / blood
  • Vancomycin / isolation & purification
  • Vancomycin / pharmacology*

Substances

  • Acetamides
  • Anti-Bacterial Agents
  • Coagulase
  • Oxazolidinones
  • Vancomycin
  • Linezolid
  • Daptomycin