耐碳青霉烯类肠杆菌科细菌KPC和NDM-1β内酰胺酶耐药基因的研究

目的检测江苏盛泽医院耐碳青霉烯类肠杆菌科细菌的KPC和NDM-1耐药基因，分析耐碳青霉烯类的耐药机制。方法采用改良Hodge试验、亚胺培南-EDTA纸片协同试验和AmpC酶三维试验检测29株耐碳青霉烯类抗生素肠杆菌科细菌产酶情况；用PCR方法检测KPC及NDM-1两种碳青霉烯酶耐药基因。结果29株分离菌中，26株菌改良Hodge试验阳性，7株亚胺培南EDTA纸片协同试验阳性，7株AmpC酶三维试验阳性，16株携带KPC型碳青霉烯酶耐药基因，未扩增出NDM-1碳青霉烯酶耐药基因。结论该院耐碳青霉烯类抗生素肠杆菌科细菌的耐药机制主要是携带KPC型碳青霉烯酶基因。

Identification of blaKec and blaNDM-1 genes in carbapenem-resistant Enterobacteri-aceae

Objective To detect blaKPC and blaNDM-1 genes in carbapenem-resistant Enterobacteriaceae isolates and explore the potential mechanism of resistance. Methods Phenotypic confirmatory tests such as modified Hodge test, imipenem-EDTA double disk synergy test and three-dimensional modified test were carried out to confirm the production of carbapenemases. The encoding genes of KPC and NDM-1 were analyzed by PCR and verified by DNA sequencing. Results Production of carbapene-mases was revealed in 26 clinical isolates of carhapenem-resistant Enterobacteriaceae by modified Hodge test, 7 isolates hy imi penem-EDTA double-disk synergy test, and 7 isolates by three-dimensional modified test. The encoding gene of KPC was iden-tified in 16 clinical isolates. The encoding gene of NDM-1 was not detected in any isolate. Conclusions Resistance or reduced susceptibility to carbapenems is mainly due to the production of KPC in these Enterobacteriaceae strains.