title: Multicentre evaluation of the in vitro activity of linezolid in the Western Pacific.
abstract: 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 (MIC(90)) 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.
authors.affiliation: Department of Microbiology and Infectious Diseases, Women's and Children's Hospital, 72 King William Road, North Adelaide, SA 5006, Australia. bellj@mail.wch.sa.gov.au
authors.forename: Jan M
authors.initials: JM
authors.lastname: Bell
authors.forename: John D
authors.initials: JD
authors.lastname: Turnidge
authors.forename: Charles H
authors.initials: CH
authors.lastname: Ballow
authors.forename: Ronald N
authors.initials: RN
authors.lastname: Jones
mesh_terms: D000081:Acetamides / Q000494:pharmacology*; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D001315:Australia / Q000453:epidemiology; D003625:Data Collection; D024881:Drug Resistance, Bacterial; D013293:Enterococcus faecalis / Q000187:drug effects; D016984:Enterococcus faecium / Q000187:drug effects; D005202:Asia, Eastern / Q000453:epidemiology; D006094:Gram-Positive Bacteria / Q000187:drug effects*; D016908:Gram-Positive Bacterial Infections / Q000453:epidemiology / Q000382:microbiology; D000069349:Linezolid; D008826:Microbial Sensitivity Tests; D023303:Oxazolidinones / Q000494:pharmacology*; D013296:Streptococcus pneumoniae / Q000187:drug effects
chemical_list: D000081:Acetamides; D000900:Anti-Bacterial Agents; D023303:Oxazolidinones; D000069349:Linezolid