Surveillance of antimicrobial resistance in clinical isolates from Tongji Hospital in 2012 / 中国感染与化疗杂志

ABSTRACT

Objective To investigate the antimicrobial resistance in the clinical strains isolated from Tongji Hospital to the antimicrobial agents commonly used in 2012.Methods Antimicrobial susceptibility was tested by Kirby-Bauer method.The minimum inhibitory concentration (MIC) of penicillin and ceftriaxone for Streptococcus pneumoniae and vancomycin for Staphylococcus spp.were determined by E-test.All data were analyzed by WHONET 5.6 software.Results A total of 8 191 strains were isolated in 2012,including gram-positive bacteria (2 815,34.4%)and gram-negative bacteria (5 376,65.6%). The top five pathogenic bacteria isolated from outpatients were Escheria coli,Pseudomonas aeruginosa,coagulase-negative Staphylococcus (CNS),Klebsiella spp.and Staphylococcus aureus.For the isolates from non-ICU inpatients,the top five were E.coli,S.aureus,Acinetobacter spp.,Klebsiella spp.and P.aeruginosa.For those isolated from ICU patients,the top five were Acinetobacter spp.,S.aureus,P.aeruginosa,Enterococcus spp.and E.coli.The prevalence of MRSA and MRCNS was 58.1% and 64.3%,respectively.Seventeen strains of vancomycin resistant Enterococcus were identified, including 13 strains of E.faecium with VanA and 4 strains of E.gallinarum with VanA and VanC.The percentage of antimicrobial resistance in E.faecium was significantly higher than that in E.faecalis (P<0.05).A total of 94 strains of carbapenem-resistant Enterobacteriaceae were detected.The prevalence of penicillin-non-susceptible S.pneumoniae in children was much higher than that in adults. The prevalence of carbapenem-resistant P.aerugonosa and Acinetobacter spp. was 28.1% and 56.2% respectively.Beta-lactamase was produced in 41.8% of the H.influenzae and 98.6% of the M. catarrhalis isolates. Conclusions The prevalence of multidrug resistant strains has been increasing, especially vancomycin-resistant Enterococcus and carbapenem-resistant Enterobacteriaceae.