Hong Jun Sung, Kim Jung Ok, Lee Hyukmin, Bae Il Kwon, Jeong Seok Hoon, Lee Kyungwon
Brain Korea 21 PLUS Project for Medical Science, Yonsei University, Seoul, Korea.
Department of Laboratory Medicine and Research Institute of Bacterial Resistance, Yonsei University College of Medicine, Seoul, Korea.
Infect Chemother. 2015 Mar;47(1):33-40. doi: 10.3947/ic.2015.47.1.33. Epub 2015 Mar 30.
The aim of this study was to investigate the molecular epidemiological characteristics of metallo-β-lactamase (MBL)-producing Pseudomonas aeruginosa clinical isolates in Korea.
Three hundred and twenty nine P. aeruginosa clinical isolates were collected from 23 general hospitals in Korea from March to June 2014. Species were identified by matrix-assited laser desorption/ionization-time of flight and 16S rRNA sequencing. Antimicrobial susceptibility was determined by disk diffusion methods. Further, minimum inhibitory concentrations of carbapenems were determined by Etest. Polymerase chain reaction and sequencing were performed to identify genes encoding MBLs. Multi-locus sequence typing and pulsed-field gel electrophoresis were performed to determine epidemiological characteristics of MBL-producing P. aeruginosa isolates.
Of the 329 isolates, 229 (69.6%) were susceptible to the carbapenems tested, including imipenem and meropenem; while 100 (30.4%) were non-susceptible to more than one of the carbapenems. Genes encoding imipenemase-6 (IMP-6) and Verona imipenemase-2 (VIM-2) MBLs were identified in 21 (6.4%) isolates (n = 17 and 4, respectively). All MBL-producing isolates showed multi-drug resistant phenotype, and a majority (n = 19) of the isolates were identified as sequence type 235 (ST235). The remaining isolates (n = 2) were identified as ST309 and ST463.
P. aeruginosa ST235 might play an important role in dissemination of MBL genes in Korea.
本研究旨在调查韩国产金属β-内酰胺酶（MBL）的铜绿假单胞菌临床分离株的分子流行病学特征。
2014年3月至6月，从韩国23家综合医院收集了329株铜绿假单胞菌临床分离株。通过基质辅助激光解吸/电离飞行时间质谱和16S rRNA测序鉴定菌种。采用纸片扩散法测定抗菌药物敏感性。此外，采用Etest法测定碳青霉烯类药物的最低抑菌浓度。通过聚合酶链反应和测序鉴定编码MBL的基因。进行多位点序列分型和脉冲场凝胶电泳以确定产MBL的铜绿假单胞菌分离株的流行病学特征。
在329株分离株中，229株（69.6%）对所检测的碳青霉烯类药物敏感，包括亚胺培南和美罗培南；而100株（30.4%）对一种以上的碳青霉烯类药物不敏感。在21株（6.4%）分离株中鉴定出编码亚胺培南酶-6（IMP-6）和维罗纳亚胺培南酶-2（VIM-2）MBL的基因（分别为n = 17和4）。所有产MBL的分离株均表现出多重耐药表型，大多数（n = 19）分离株被鉴定为序列型235（ST235）。其余分离株（n = 2）被鉴定为ST309和ST463。
铜绿假单胞菌ST235可能在韩国MBL基因的传播中起重要作用。
