神经外科碳青霉烯类耐药肠杆菌科细菌的耐药率及耐药基因分析

Analysis of drug resistance rate and drug resistance genes of Enterobacteria resistant to carbapenemase in neurosurgery

目的探讨神经外科碳青霉烯类耐药肠杆菌科细菌(CRE)的流行菌株、耐药率、碳青霉烯耐药表型及耐药基因类型。方法收集2019年12月至2020年12月该院神经外科感染患者送检标本中分离的30株CRE,采用微量肉汤稀释法进行体外药敏试验,然后采用改良碳青霉烯灭活法试验和碳青霉烯酶抑制剂增强试验对肠杆菌科细菌产生的碳青霉烯酶进行检测并分型,同时采用PCR作为金标准检测碳青霉烯酶的基因型。结果神经外科的30株CRE对抗菌药物黏菌素、替加环素均敏感,对其他药物耐药率均较高。30株CRE全部产碳青霉烯酶,其中20株产blaKPC-2,8株产blaNDM-1,1株同时产blaKPC-2和blaNDM-1,1株产blaKPC-3。耐药表型检测与PCR基因测序的符合率为96.7%(29/30)。结论神经外科患者感染的CRE以肺炎克雷伯菌为主,对大多数抗菌药物均高度耐药,耐药基因以blaKPC-2为主,需要做好医院感染的隔离防护。

Objective To study the prevalent strains,resistance rates,carbapenem resistance phenotypes and resistance gene types of Enterobacteria resistant to carbapenemase(CRE)in neurosurgery.Methods Thirty CRE isolated from specimens submitted by neurosurgery patients from December 2019 to December 2020 were collected.Micro broth dilution method for in vitro drug susceptibility test was used,then modified carbapenem inactivation test and carbapenemase inhibitor enhancement test were used to detect and the carbapenemase produced by Enterobacteriaceae bacteria was typed,and use PCR as the gold standard detection of carbapenemase genotype.Results CRE in neurosurgery was sensitive to the antibacterial drugs colistin and tigecycline,and had a high resistance rate to other drugs.All 30 CRE strains produced carbapenemase,of which 20 strains produced blaKPC-2.Eight strains produced blaNDM-1,one strain produced both blaKPC-2 and blaNDM-1,and one strain produced blaKPC-3.The coincidence rate of drug resistance phenotype detection and PCR gene sequencing was 96.7%(29/30).Conclusion The CRE infected by neurosurgery patients are mainly Klebsiella pneumoniae,which are highly resistant to most antibacterial drugs,and the main resistance gene is blaKPC-2.It is necessary to do a good job in the isolation and protection of hospital infections.