Characterization of carbapenemases, extended spectrum β-lactamases and molecular epidemiology of carbapenem-non-susceptible Enterobacter cloacae in a Chinese hospital in Chongqing.

摘要: Carbapenem-resistant Enterobacteriaceae, including strains from multiple species harboring metallo-β-lactamases (IMP, NDM or VIM) and non-metallo (KPC) carbapenemases, as well those combining an extended-spectrum β-lactamase (ESBL) enzyme with porin loss, present increasingly urgent clinical danger. The aim of this study was to characterize the carbapenemases ESBLs in carbapenem-non-susceptible (CNS) Enterobacter cloacae (E. cloacae) isolates a Chinese teaching hospital. A total 986 non-duplicated E. collected between September 2009 February 2012 were analyzed via antimicrobial susceptibility testing. Carbapenemase ESBL genes examined using PCR amplification DNA sequencing. Clonal relatedness investigated by pulsed-field gel electrophoresis (PFGE) dendrogram analysis. We demonstrated that CNSs prevalent (35/986, 3.55%) cloacae. Phenotypes respectively found 9 (25.7%) 23 (65.7%) 35 CNS strains. KPC-2, IMP-8, IMP-26, NDM-1, TEM-6, CTX-M-3', CTX-M-14' SHV-12 type β-lactamases identified 3 (8.6%), 5 (14.3%), 1 (2.9%), 13 (37.1%), (25.7%), 8 (22.9%) isolates, respectively. Importantly, resistance be co-expressed same isolates. PFGE analysis showed clonal diversity among these Our suggested over-production contributed together China. Furthermore, decreased carbapenems cloaca hospital might arise stepwise accumulations drug-resistance determinants different clones. prevalence not caused dissemination. Most importantly, we isolate co-expressing IMP-26 which is first reported best our knowledge. This also report NDM-1-producing Enterobacteriaceae mainland