Infect Chemother.  2006 Apr;38(2):85-90.

In Vitro Activities of Daptomycin Against Recent Clinical Isolates of Methicillin-resistant Staphylococci and Vancomycin-resistant Enterococci in Korea

Affiliations
  • 1Department of Laboratory Medicine, Kwandong University College of Medicine, Kyunggi, Korea.
  • 2Department of Laboratory Medicine, Yonsei University College of Medicine, Seoul, Korea. leekcp@yumc.yonsei.ac.kr
  • 3Research Institute of Bacterial Resistance, Yonsei University College of Medicine, Seoul, Korea.

Abstract

BACKGROUND: Daptomycin is a novel cyclic lipopeptide antibiotic that exhibits in vitro bactericidal activity against gram-positive pathogens including methicillin-resistant staphylococci and vancomycin-resistant enterococci. The aim of this study is to determine the in vitro activities of daptomycin against recent clinical isolates of methicillin-resistant staphylococci and vancomycin-resistant enterococci in Korea.
MATERIALS AND METHODS
A total of 117 clinical strains of methicillin-resistant staphylococci and vancomycin-resistant enterococci were isolated at a tertiary-care hospital in Korea in 2004. Susceptibility to daptomycin was tested by the CLSI broth microdilution method using Mueller-Hinton broth (MHB) which was adjusted to contain a final concentration of 50 microgram/mL of ionized calcium (Ca2+). Susceptibilities to ampicillin, oxacillin, levofloxacin, vancomycin, and linezolid were tested by the CLSI agar dilution method.
RESULTS
All isolates of methicillin-resistant S. aureus and coagulase-negative staphylococci were inhibited by 1 microgram/mL of daptomycin, and MIC90s were 1 microgram/mL, which were similar to those of vancomycin and linezolid. MIC90s of daptomycin for vancomycin-resistant E. faecalis and E. faecium were 0.5 microgram/mL and 2 microgram/mL, respectively, and all isolates were susceptible to daptomycin. MIC90s of linezolid and levofloxacin for vancomycin-resistant enterococci were 1-2 microgram/mL and 64 microgram/mL, respectively. Resistance rates of vancomycin-resistant E. faecalis and E. faecium to levofloxacin were 100% and 96%, respectively. Daptomycin MICs in MHB supplemented to 20-25 microgram/ml of Ca2+ were 2-8 fold higher than those in MHB supplemented to 50 microgram/mL of Ca2+.
CONCLUSION
Daptomycin is very active in vitro against methicillin-resistant staphylococci and vancomycin-resistant enterococci isolated in Korea, and it is important to test in vitro activity of daptomycin using MHB containing 50 microgram/mL of Ca2+.

Keyword

Daptomycin; MRSA; VRE; Staphylococci; Enterococci

MeSH Terms

Agar
Ampicillin
Calcium
Daptomycin*
Korea*
Levofloxacin
Linezolid
Methicillin Resistance*
Methicillin-Resistant Staphylococcus aureus
Oxacillin
Vancomycin
Agar
Ampicillin
Calcium
Daptomycin
Oxacillin
Vancomycin
Full Text Links
  • IC
Actions
Cited
CITED
export Copy
Close
Share
  • Twitter
  • Facebook
Similar articles
Copyright © 2024 by Korean Association of Medical Journal Editors. All rights reserved.     E-mail: koreamed@kamje.or.kr