摘要
目的评价改良碳青霉烯灭活试验(modified carbapenem inactivation method,mCIM)和EDTA碳青霉烯灭活试验(EDTA-carbapenem inactivation method,eCIM)对肠杆菌科细菌碳青霉烯酶的检测性能。方法收集2017年1月至2018年9月重庆市16家区县医院临床分离的136株碳青霉烯耐药或敏感的肠杆菌科细菌,采用PCR方法检测碳青霉烯酶基因,mCIM和eCIM筛选碳青霉烯酶表型,并对基因检测结果与表型筛选试验结果进行分析和评价。结果85株碳青霉烯耐药肠杆菌科细菌中79株检出碳青霉烯酶基因,共表达A类和B类碳青霉烯酶基因8株,占比10.13%(8/79),碳青霉烯酶表型筛选试验mCIM阳性78株,eCIM阳性44株。51株碳青霉烯敏感菌株未检测到碳青霉烯耐药基因且mCIM均为阴性。mCIM筛选肠杆菌科细菌碳青霉烯酶的灵敏度为98.7%(95%CI:92.2~99.9),特异性为100.0%(95%CI:92.1~100.0),Kappa值为0.985;eCIM筛选金属酶灵敏度为85.7%(95%CI:72.1~93.6),特异性为94.4%(95%CI:80.0~99.0),Kappa值为0.787;eCIM筛选丝氨酸酶灵敏度为89.5%(95%CI:74.3~96.6),特异性为100.0%(95%CI:90.6~100.0),Kappa值为0.904。结论mCIM联合eCIM检测可有效筛选产碳青霉烯酶菌株,但随着共表达A类和B类碳青霉烯酶菌株的分离率增加会降低对金属酶筛选的灵敏度。
Objective To evaluate the performance of modified carbapenem inactivation method(mCIM)and EDTA carbapenem inactivation method(eCIM)in detection of carbapenemase in Enterobacteriaceae Bateremia.Methods Polymerase chain reaction(PCR)was used to detect carbapenemase gene in 136 strains of carbapenem-resistant and-sensitive Enterobacteriaceae clinically isolated from 16 county-level hospital during January 2017 and September 2018.Meanwhile,the phenotype of obtained carbapenemase gene was screened by mCIM and eCIM.The results of gene detection and phenotypic screening test were analyzed and evaluated.Results Seventy-nine strains out of 85 carbapenem-resistant Enterobacteriaceae strains(CRE)were positive to carbapenemase gene by PCR,and 8 strains expressed class A and B carbapenemase gene,accounting for 10.13%(8/79).Seventy-eight strains of 85 CRE strains were positive detected by mCIM,and 44 strains were identified to be positive by eCIM among them.The carbapenem-resistant genes were not detected in the 51 carbapenem-sensitive strains by mCIM results.Screening the carbapenemase by mCIM had the sensitivity of 98.7%(95%CI:92.2~99.9),the specificity of 100.0%(95%CI:92.1~100.0),and the Kappa value of 0.985.When eCIM screened metallo-β-lactamase,the sensitivity was 85.7%(95%CI:72.1~93.6),the specificity was 94.4%(95%CI:80.0~99.0),and the Kappa value was 0.787.Screening serine carbapenemase,the sensitivity of eCIM was 89.5%(95%CI:74.3~96.6),the specificity was 100.0%(95%CI:90.6~100.0),and the Kappa value was 0.904.Conclusion Combination of mCIM and eCIM can screen carbapenemase-producing Enterobacteriaceae effectively.However,the sensitivity of the combined detection to screen metallo-β-lactamase will be reduced with the emergence of a large number of co-expressed class A and B carbapenemase-producing Enterobacteriaceae.
作者
王永红
刘航
邹家齐
马华兰
夏云
WANG Yonghong;LIU Hang;ZOU Jiaqi;MA Hualan;XIA Yun(Department of Clinical Laboratory,the First Affiliated Hospital of Chongqing Medical University,Chongqing,400016;Department of Clinical Laboratory,Chongqing Qianjiang Central Hospital,Chongqing,409099,China)
出处
《第三军医大学学报》
CAS
CSCD
北大核心
2020年第5期466-472,共7页
Journal of Third Military Medical University
基金
重庆市科卫联合医学科研项目(2018MSXM104)。
