title: Carbapenem susceptibilities and non-susceptibility concordance to different carbapenems amongst clinically important Gram-negative bacteria isolated from intensive care units in Taiwan: results from the Surveillance of Multicentre Antimicrobial Resistance in Taiwan (SMART) in 2009.
abstract: To investigate the in vitro susceptibilities to various carbapenems amongst clinical Gram-negative bacteria isolated from patients in intensive care units of ten major teaching hospitals in Taiwan in 2009, a survey was conducted to determine the minimum inhibitory concentrations (MICs) of ertapenem, imipenem, meropenem and doripenem against isolates of Enterobacteriaceae (n = 594), Pseudomonas aeruginosa (n = 185), Acinetobacter baumannii (n = 192) and Burkholderia cepacia (n = 23) using the agar dilution method. Susceptibilities were determined according to 2009, 2011 and 2012 MIC breakpoints recommended by the CLSI as well as 2012 MIC breakpoints recommended by EUCAST. Based on CLSI 2012 criteria, the ertapenem susceptible rate was 93%, 81%, 68% and 92% for Escherichia coli, Klebsiella pneumoniae, Enterobacter cloacae and Serratia marcescens, respectively. All Proteus mirabilis and Morganella morganii isolates were susceptible to ertapenem; however, 64% of P. mirabilis and all M. morganii isolates were non-susceptible to imipenem. Meropenem and doripenem had better activities than imipenem against ertapenem-non-susceptible Enterobacteriaceae isolates. E. coli, K. pneumoniae and E. cloacae with ertapenem MICs≥4 mg/L were synchronously not susceptible to imipenem, meropenem and doripenem. Imipenem susceptibility was 65% and 29% for P. aeruginosa and A. baumannii, respectively. Additionally, P. aeruginosa and A. baumannii isolates with imipenem MICs≥8 mg/L were also not susceptible to meropenem and doripenem. These data provide a better understanding of choosing appropriate carbapenem agents to treat infections caused by ertapenem-non-susceptible Enterobacteriaceae as well as P. aeruginosa and A. baumannii isolates with imipenem MICs≥4 mg/L.
authors.affiliation: Department of Emergency Medicine, Wan Fang Hospital, Taipei Medical University, Taipei, Taiwan.
authors.forename: Shio-Shin
authors.initials: SS
authors.lastname: Jean
authors.forename: Po-Ren
authors.initials: PR
authors.lastname: Hsueh
authors.forename: Wen-Sen
authors.initials: WS
authors.lastname: Lee
authors.forename: Kwok-Woon
authors.initials: KW
authors.lastname: Yu
authors.forename: Chun-Hsing
authors.initials: CH
authors.lastname: Liao
authors.forename: Feng-Yi
authors.initials: FY
authors.lastname: Chang
authors.forename: Wen-Chien
authors.initials: WC
authors.lastname: Ko
authors.forename: Jiunn-Jong
authors.initials: JJ
authors.lastname: Wu
authors.forename: Yen-Hsu
authors.initials: YH
authors.lastname: Chen
authors.forename: Yao-Shen
authors.initials: YS
authors.lastname: Chen
authors.forename: Jien-Wei
authors.initials: JW
authors.lastname: Liu
authors.forename: Min-Chi
authors.initials: MC
authors.lastname: Lu
authors.forename: Cheng-Yi
authors.initials: CY
authors.lastname: Liu
authors.forename: Carlos
authors.initials: C
authors.lastname: Lam
authors.forename: Ray-Jade
authors.initials: RJ
authors.lastname: Chen
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D015780:Carbapenems / Q000494:pharmacology*; D006090:Gram-Negative Bacteria / Q000187:drug effects* / Q000302:isolation & purification; D016905:Gram-Negative Bacterial Infections / Q000453:epidemiology* / Q000382:microbiology; D006801:Humans; D007362:Intensive Care Units; D008826:Microbial Sensitivity Tests; D015995:Prevalence; D013624:Taiwan / Q000453:epidemiology; D018440:beta-Lactam Resistance
chemical_list: D000900:Anti-Bacterial Agents; D015780:Carbapenems