耐碳青霉烯类肠杆菌科细菌KPC与NDM的研究

Investigation of blaKPC and blaNDM of carbapenem-resistant Enterobacteriaceae

目的检测耐碳青霉烯类肠杆菌科细菌的KPC和NDM耐药基因,分析耐碳青霉烯类的耐药机制。方法收集2014年1月-2015年6月医院27株对碳青霉烯类抗菌药物敏感性降低的肠杆菌科细菌,筛选出耐亚胺培南或美罗培南的肠杆菌科细菌,采用改良Hodge试验初筛,聚合酶链反应(PCR)扩增检测细菌产KPC和NDM耐药基因。结果针对碳青霉烯类抗菌药物耐药的27株菌,用改良的Hodge试验5株阳性,有9株经PCR扩增检测细菌产KPC基因,有13株经PCR扩增检测细菌产NDM耐药基因;基因测序比对结果为KPC-2型碳青霉烯酶和NDM-1型耐药基因。结论耐碳青霉烯类肠杆菌科细菌耐药机制主要携带KPC-2型碳青霉烯酶耐药基因和NDM-1型耐药基因,临床与实验室应引起重视。

OBJECTIVE To detect blaKPC and blaNDM of carbapenem-resistant Enterobacteriaceae, and investi- gate the mechanism of carbapenem-resistance in Enterobacteriaceae. METHODS A total of 27 strains of carbapen- em-resistant Enterobacteriaceae from Jan. 2014 to Jun. 2015 were collected. Enterobacteriaceae bacteria which were resistant to imipenem or meropenem or both of them were screened. Modified Hodge test was used for early screening, and polymerase chain reaction （PCR） amplification was used to detect drug-resistant genes sequencing of producing KPC and NDM. RESULTS A total of 5 strains from 27 isolated strains were positive in modified Hodge test, and there were 9 strains carrying blaKPC carbapenem-resistant gene and 13 strains carrying blaNDM carbapenem-resistant gene were detected by PCR. Genetic sequencing showed that KPC-2 type carbon penicillium enzyme and NDM-1 type resistant genes were related to drug-resistance. CONCLUSION The mechanism of carbap- enem-resistance in Enterobacteriaceae is mainly due to KPC-2 type carbon peniciUium enzyme and NDM-1 type re- sistant genes, which should be concerned in the clinical and laboratory.