Changes in resistance of Staphylococcus aureus to vancomycin and linezolid in Sichuan Province in 2011-2015 / 中国感染控制杂志

ABSTRACT

Objective To investigate the resistance of Staphylococcus aureus (S.aureus) to vancomycin and linezolid in Sichuan Province, and provide reference for clinical anti-infection treatment.Methods S.aureus and methicillin-resistant S.aureus(MRSA) from 71 hospitals in Sichuan Province in 2011-2015 were collected, minimum inhibitory concentration(MIC) values of vancomycin and linezolid against S.aureus and MRSA in each year were calculated.Results A total of 51 976 strains of S.aureus were collected in 5 years, 14 361 of which were MRSA, isolation rate of MRSA decreased from 36.02％ in 2011 to 25.56％ in 2015, which showed a downward trend (x2=160.72,P<0.05).From 2011 to 2015, MIC50 of vancomycin against S.aureus were 1, 0.5, 0.5, 1, and 1μg/mL respectively,MIC90 increased from 1μg/mL to 2μg/mL;the mean MIC50 of linezolid was 2μg/mL,MIC90 increased from 2μg/mL to 4μg/mL.Change in MIC50 and MIC90 of vancomycin against MRSA in 2011-2015 were obvious, which increased from 0.5, 1μg/mL to 2μg/mL respectively;the mean MIC50 of linezolid was 2μg/mL,MIC90 increased from 2μg/mL to 4μg/mL.Conclusion The isolates rate of MRSA had a decreasing trend,but there is a upward trend of MIC50 and MIC90 of vancomycin and linezolid against MRSA, bacterial resistance surveillance needs to be strengthened to provide evidence for rational clinical antimicrobial therapy.