Multiresistance to antimicrobial agents is common in staphylococci and pneumococci isolates in the Western Pacific region. The activity of linezolid, a new oxazolidinone, was evaluated against a spectrum of Gram-positive species collected in the region. Eighteen laboratories from six countries in the Western Pacific examined the linezolid susceptibility of 2143 clinical isolates of Staphylococcus aureus, coagulase-negative staphylococci (CoNS) and Enterococcus spp. using broth microdilution or disc diffusion methodology. For Streptococcus pneumoniae (n=351) and other streptococci (n=83), Etest (AB Biodisk, Solna, Sweden) strips were used. Results were compared with other common and important antimicrobials. Linezolid-resistant strains were not detected among streptococci or staphylococci, including a significant proportion of S. aureus strains that were multiresistant. Almost all enterococci, including 14 vancomycin-resistant Enterococcus faecium, were linezolid susceptible. A small proportion of enterococci (0.8%) were intermediate to linezolid, and one strain of Enterococcus faecalis had a zone diameter of 20 mm (resistant). The linezolid MIC ranges (MIC90) of those strains tested by broth microdilution or Etest were: 1-4 mg/L (2 mg/L) for S. aureus, 0.5-4 mg/L (2 mg/L) for CoNS, 0.5-4 mg/L (2 mg/L) for Enterococcus spp., 0.12-2 mg/L (1 mg/L) for S. pneumoniae and 0.25-2 mg/L (1 mg/L) for Streptococcus spp. There was no difference in linezolid susceptibility between countries or between multiresistant and susceptible strains of each species monitored.
Bibliographical noteFunding Information:
This study was supported by an educational/research grant from Pharmacia and Upjohn (Kalamazoo MI, USA). ZAPS Western Pacific Regional Participants are as follows: Australia: J. Turnidge (Women’s and Children’s Hospital, Adelaide); R. Benn (Royal Prince Alfred Hospital, Sydney); L. Grayson (Monash Medical Centre, Melbourne); J. Fao-agali (Royal Brisbane Hospital, Brisbane); K. Christiansen (Royal Perth Hospital, Perth). China: A. Cheng (Prince of Wales Hospital, Hong Kong); D. Tsang (Queen Elizabeth Hospital, Hong Kong). Japan: S. Kohno (Nagasaki University School of Medicine, Nagasaki); K. Yamaguchi (Toho University, Tokyo); M. Kahu (Tohoku University, Aoba-ku Sendai). Korea: J. H. Woo (University of Ulsan, Seoul); K. W. Choi (Seoul National University Hospital, Seoul); K. W. Lee (Yonsei University, Seoul). Singapore: M. Yeo (Singapore General Hospital); G. Kumarasinghe (National University Hospital). Taiwan: Po-Ren Hsueh (National Taiwan University Hospital, Taipei); Y. C. Liu (Veterans General Hospital, Kaohsiung); H. S. Leu (Chang-Gung Memorial Hospital, Taoyuan).
All Science Journal Classification (ASJC) codes
- Microbiology (medical)
- Infectious Diseases
- Pharmacology (medical)