Surveillance of bacterial resistance in Peking Union Medical College Hospital during 2012 / 中国感染与化疗杂志

ABSTRACT

Objective To investigate the profile of antimicrobial resistance in clinical isolates from the patients in Peking Union Medical College Hospital during 2012.Methods A total of 6 662 nonduplicate clinical isolates were collected.Disc diffusion test or Kirby-Bauer method and automated systems were employed to study the antimicrobial resistance.The data were analyzed by WHONET 5.6 software according to CLSI 2012 breakpoints.Results Of the 6 662 bacterial strains included in this analysis, gram negative organisms and gram positive cocci accounted for 66.7% (4 446/6 662)and 33.3% (2 216/6 662),respectively. The top 10 most frequently isolated microorganisms were E.coli (17%),P .aeruginosa (11.4%),A.baumannii (11.4%), S.aureus (11.2%),K.pneumoniae (9.2%),E.faecalis (8.4%),E.faecium (4.1%),coagulase negative Staphylococcus (3.3%),E.cloacae (3.1%)and S.maltophilia (3.1%).About 39.9% of the S.aureus strains and 73.4% of the coagulase negative Staphylococcus were methicillin-resistant.No staphylococcal strains were found resistant to vancomycin,teicoplanin or linezolid.A few of vancomycin-or teicoplanin-resistant strains were identified in both E.faecium and E.faecalis.No lin-ezolid resistant strains were found.ESBLs-producing strains accounted for 53.0%,25.7% and 27.0% in E.coli,Klebsiella spp.(K.pneumoniae and K.oxytoca)and P .mirabilis, respectively.The Enterobacteriaceae strains were still highly susceptible to carbapenems. Overall, less than 2.6% of these strains were resistant to carbapenems.A few pan-re-sistant strains of K.pneumoniae (0.7%,4/615)were iden-tified.About 20.3% and 13.6% of the P .aeruginosa isolates were resistant to imipenem and meropenem,respectively.P . aeruginosa isolates showed the lowest resistance rate (7.2%)to amikacin.And 72.8% and 75.2% of A.baumannii strains were resistant to imipenem and meropenem.A.baumannii isolates showed relatively low resistance rate to cefoperazone-sulbac-tam (51.2%)and minocycline (30.2%).The prevalence of pan-resistant strains was 43.5% in A.baumannii and 1.4% in P . aeruginosa.Conclusions Bacterial resistance is still increasing,especially pan-resistant A.baumannii strains.It is mandatory to take effective measures to control hospital infections and improve rational antibiotic use.