CHINET 2013 surveillance of bacterial resistance in China

Objective To investigate the susceptibility and resistance of clinical isolates collected from hospitals in several regions of China.Methods Fourteen general hospitals and two children's hospitals were involved in this program.Antimicrobial susceptibility testing was carried out according to a unified protocol using Kirby-Bauer method or automated Systems.Results were analyzed according to CLSI 2013 breakpoints.Results A total of 84 572 clinical isolates were collected from January to December 2013,of which gram negative organisms and gram positive cocci accounted for 73.0%and 27.0%respectively.Methicillin-resistant strains in S.aureus(MRSA)and coagulase negative Staphylococcus(MRCNS)accounted for an average of 45.2% and 73.5% respectively.The resistance rates of methicillin-resistant strains toβ-lactams and other antimicrobial agents were much higher than those of methicillin-susceptible strains.However,92.2% of MRSA strains were still susceptible to trimethoprim-sulfamethoxazole while 87.4% of MRCNS strains were susceptible to rifampin.No staphylococcal strains were found resistant to vancomycin,teicoplanin or linezolid.In Enterococcus spp.,the resistance rates of E.faecalis strains to most tested drugs(except chloramphenicol)were much lower than those of E.faecium.Some strains of both species were resistant to vancomycin.Vancomycin-resistant strains of E.faecalis and E.faecium were mainly VanA type based on their phenotype.Regarding non-meningitis S.pneumoniae strains,the prevalence of penicillin-susceptible S.pneumoniae and penicillin-intermediate S.pneumoniae strains isolated from both adults and children were lower than those isolated in2012,but the prevalence of penicillin-resistant S.pneumoniae strains increased.The prevalence of ESBLs producing strains was 54.0%in E.coli,31.8%in Klebsiellaspp.(K.pneumoniae and K.oxytoca)and 16.5%in Proteus mirabilis isolates on average.ESBLs-producing Enterobacteriaceae strains were more resistant than non-ESBLs-producing strains in terms of antibiotic resistance rates.The strains of Enterobacteriaceae were still highly susceptible to carbapenems.Overall less than 7.0%of these strains were resistant to carbapenems.About 62.8% and 59.4% of Acinetobacter spp.(A.baumannii accounts for 89.2%)strains were resistant to imipenem and meropenem,respectively.Compared with the data of year 2012,extensively-drug resistant strains in K.pneumoniae and A.baumannii decreased.Conclusions The antibiotic resistance of clinical bacterial isolates is growing in2013.The disseminated multi-drug or pan-drug resistant strains in a special region poses a serious threat to clinical practice and implies the importance of strengthening infection control.