Lai Kaisheng, Ma Yanning, Guo Ling, An Jingna, Ye Liyan, Yang Jiyong
Department of Microbiology, Chinese PLA General Hospital, 301 Hospital, 28# Fuxing Road, Beijing, 100853, China.
Ann Clin Microbiol Antimicrob. 2017 Jun 19;16(1):42. doi: 10.1186/s12941-017-0218-9.
IMP-producing Klebsiella pneumoniae (IMPKpn) exhibits sporadic prevalence in China. The mechanisms related to the spread of IMPKpn remain unclear.
Carbapenem non-susceptible K. pneumoniae isolates were collected from our hospital. The genetic relatedness, antimicrobial susceptibility, as well as sequence types (ST) were analyzed by pulsed-field gel electrophoresis (PFGE), VITEK 2 AST test Kit, and multilocus sequence typing (MLST), respectively. S1-PFGE, Southern blot analysis and multiple PCR amplification were used for plasmid profiling.
Between October 2009 and June 2016, 25 non-repetitive IMPKpn isolates were identified. PFGE results showed that these isolates belonged to 20 genetically unrelated IMPKpn strains. Diverse STs were identified by MLST. Most strains carried bla , followed by bla . Four incompatibility types of bla -carrying plasmids were identified, which included A/C (n = 2), B/O (n = 2), L/M (n = 1) and N (n = 14), while type of other one plasmid failed to be determined.
The IMPKpn isolates exhibited sporadic prevalence in our hospital. IncN types of plasmids with various sizes have emerged as the main platform mediating the spread of the bla genes in our hospital.
产 IMP 型肺炎克雷伯菌（IMPKpn）在中国呈散发性流行。与 IMPKpn 传播相关的机制仍不清楚。
从我院收集碳青霉烯类不敏感的肺炎克雷伯菌分离株。分别采用脉冲场凝胶电泳（PFGE）、VITEK 2 AST 检测试剂盒和多位点序列分型（MLST）分析其遗传相关性、抗菌药物敏感性及序列型（ST）。采用 S1-PFGE、Southern 印迹分析和多重 PCR 扩增进行质粒分析。
2009 年 10 月至 2016 年 6 月，共鉴定出 25 株非重复性 IMPKpn 分离株。PFGE 结果显示，这些分离株属于 20 个遗传不相关的 IMPKpn 菌株。通过 MLST 鉴定出多种 ST 型。大多数菌株携带 bla，其次是 bla。鉴定出四种携带 bla 的质粒不相容类型，包括 A/C（n = 2）、B/O（n = 2）、L/M（n = 1）和 N（n = 14），而另一种质粒的类型未能确定。
IMPKpn 分离株在我院呈散发性流行。不同大小的 IncN 型质粒已成为介导我院 bla 基因传播的主要平台。
