|
 |
 Home > Available Issues |
|
|
 Original Articles |
| In Vitro Activities of Daptomycin Against Recent Clinical Isolates ofMethicillin-resistant Staphylococci and Vancomycin-resistant Enterococci in Korea |
| Hyukmin Lee, M.D.1,3, Seo-Jin Park, M.D.2, Yeoung Seon Choi3, Doe-Young Park3, Kyoung Ho Roh, M.D.2,3Jong Hwa Yum, Ph.D.2,3, Dongeun Yong, M.D.2,3, Kyungwon Lee, M.D.2,3, and Yun Sop Chong, Ph.D.2,3 |
| 1Department of Laboratory Medicine, Kwandong University College of Medicine, Kyunggi, Korea2Department of Laboratory Medicine and 3Research Institute of Bacterial ResistanceYonsei University College of Medicine, Seoul, Korea |
Vol.38 Num.2 (p85~90)
|
|
|
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 μg/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 μg/mL of daptomycin, and MIC90s were 1 μg/mL, which were similar to those of vancomycin and linezolid. MIC90s of daptomycin for vancomycin-resistant E. faecalis and E. faecium were 0.5 μg/mL and 2 μg/mL, respectively, and all isolates were susceptible to daptomycin. MIC90s of linezolid and levofloxacin for vancomycin-resistant enterococci were 1-2 μg/mL and 64 μg/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 μg/ml of Ca2+ were 2-8 fold higher than those in MHB supplemented to 50 μg/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 μg/mL of Ca2+. |
|
|
Keywords : Daptomycin, MRSA, VRE, Staphylococci, Enterococci |
|
|
|
|
|
|
|
|
