ABSTRACT
Objective To investigate the antimicrobial resistance profile of the clinical isolates collected from selected hospitals across China. Methods Twenty-nine general hospitals and five 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 interpreted according to CLSI 2017 breakpoints. Results A total of 190 610 clinical isolates were collected from January to December 2017, of which gram negative organisms accounted for 70.8％ (134 951/190 610) and gram positive cocci 29.2％ (55 649/190 610). The prevalence of methicillin-resistant strains was 35.3％ in S. aureus (MRSA) and 80.3％ in coagulase negative Staphylococcus (MRCNS) on average. MR strains showed much higher resistance rates to most of the other antimicrobial agents than MS strains. However, 91.6％ of MRSA strains were still susceptible to trimethoprim-sulfamethoxazole, while 86.2％ of MRCNS strains were susceptible to rifampin. No staphylococcal strains were found resistant to vancomycin. E. faecalis strains showed much lower resistance rates to most of the drugs tested (except chloramphenicol) than E. faecium. Vancomycin-resistant Enterococcus (VRE) was identified in both E. faecalis and E. faecium. The identified VRE strains were mainly vanA, vanB or vanM type based on phenotype or genotype. The proportion of PSSP or PRSP strains in the non-meningitis S.pneumoniae strains isolated from children decreased but the proportion of PISP strains increased when compared to the data of 2016. Enterobacteriaceae strains were still highly susceptible to carbapenems. Overall, less than 10％ of these strains (excluding Klebsiella spp.) were resistant to carbapenems. The prevalence of imipenem-resistant K. pneumoniae increased from 3.0％ in 2005 to 20.9％ in 2017, and meropenem-resistant K. pneumoniae increased from 2.9％ in 2005 to 24.0％ in 2017, more than 8-fold increase. About 66.7％ and 69.3％ of Acinetobacter (A. baumannii accounts for 91.5％) strains were resistant to imipenem and meropenem, respectively. Compared with the data of year 2016, P. aeruginosa strains showed decreasing resistance rate to carbapenems. Conclusions Bacterial resistance is still on the rise. It is necessary to strengthen hospital infection control and stewardship of antimicrobial agents. The communication between laboratorians and clinicians should be further improved in addition to surveillance of bacterial resistance.
ABSTRACT
Objective To investigate the susceptibility profile of clinical isolates collected from hospitals across China.Methods Twenty-six general hospitals and four 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 2016 breakpoints.Results A total of 153 059 clinical isolates were collected from Junuary to December 2016,of which gram-negative organisms and gram-positive cocci accounted for 71.6％ and 28.4％,respectively.The overall prevalence of methicillin-resistant strains was 38.4％ in S.aureus (MRSA) and 77.6％ in coagulase negative staphylococcus (MRCNS),respectively.The resistance rates of methicillin-resistant strains to most of other antimicrobial agents were much higher than those of methicillin-susceptible strains.However,92.3％ of the MRSA strains were still sensitive to trimethoprim-sulfamethoxazole,while 86.5％ of the MRCNS strains were susceptible to rifampin.No staphylococcal strains were found resistant to vancomycin or teicoplanin.The resistance rates of E.faecalis strains to most drugs tested (except chloramphenicol) were much lower than those of E.faecium.A few strains of both species were resistant to vancomycin.Vancomycin resistant E.faecalis and E.faecium strains were mainly VanA,VanB or VanM type based on their phenotype or genotype.Regarding the non-meningitis S.pneumoniae strains,the prevalence of PSSP or PISP strains isolated from children was higher than that isolated in 2015,but the prevalence of PRSP strains decreased.However,the prevalence of PISP and PRSP strains isolated from adults was lower than that isolated in 2015.The prevalence of ESBLs-producing strains was 45.2％ in E.coli,25.2％ in Klebsiella spp.(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 rate.The strains of Enterobacteriaceae were still highly susceptible to carbapenems.Overall,less than 10％ of these strains were resistant to carbapenems.About 68.6％ and 71.4％ ofAcinetobacter spp.(A.baumannii accounts for 90.6％) strains were resistant to imipenem and meropenem,respectively.The prevalence of extensively-drug resistant strains in P.aeruginosa was higher than that in 2015.Conclusions Bacterial resistance to commonly used antibiotics is still on the rise.It is necessary to strengthen hospital infection control and management of clinical use of antimicrobial agents,and maintain good practice in surveillance of bacterial resistance.
ABSTRACT
Antimicrobial resistance threatens the effective treatment of bacterial infections and is a serious problem worldwide. Multidrug-resistant bacteria are difficult to treat and the treatment outcome is worse than with susceptible bacteria. In Korea, the antibiotic resistance rates of the major Gram-positive bacteria methicillin-resistant Staphylococcus aureus (MRSA), vancomycin-resistant enterococcus (VRE), and penicillin-resistant Streptococcus pneumoniae (PRSP) are very high. Clinicians should know the risk factors for developing multidrug-resistant bacterial infection, update the changing local epidemiology of resistant bacteria, and choose appropriate antibiotics in clinical practice. The overuse and misuse of broad spectrum antibiotics should be avoided. This review focuses on the epidemiology and risk factors of MRSA, VRE, and PRSP, the major multidrug-resistant Gram-positive bacteria.