2种常用肺炎克雷伯菌碳青霉烯类抗菌药物敏感性试验卡性能评价

Performance evaluation of GN13 and NM38 to determine the drug susceptibility of carbapenems against Klebsiella pneumoniae

目的评价2种常用全自动微生物鉴定系统配套药物敏感性试验卡(GN13、NM38)检测肺炎克雷伯菌对碳青霉烯类抗菌药物敏感性的可靠性。方法收集2016年1月—2017年8月黄山市人民医院分离自临床样本的168株肺炎克雷伯菌,分别采用GN13、 NM38及微量肉汤稀释法测定其对碳青霉烯类抗菌药物的敏感性。以微量肉汤稀释法为金标准,对GN13和NM38的检测结果进行分析。采用改良碳青霉烯类灭活试验(mCIM)检测碳青霉烯酶,分析经仪器高级专家系统(AES)推测或预警提示为产碳青霉烯酶的可靠性。结果以微量肉汤稀释法为金标准, GN13与NM38检测结果的分类一致率(CA)均>90%。检测结果经AES修正后,GN13对亚胺培南的一般错误(MIE)和重大错误(ME)均降低了0.6%,对厄他培南的MIE增加了0.6%,均未出现严重错误(VME); NM38对亚胺培南的MIE、ME、VME分别为1.19%、1.19%、2.97%,对厄他培南的MIE、ME、VME分别为3.6%、0.0%、0.6%。mCIM表型检测结果显示碳青霉烯酶阳性率为27.4%(46/168),经AES修正后GN13推测和NM38预测产碳青霉烯酶的阳性率分别为31.0%和30.4%,与mCIM一致(P>0.05)。结论 GN13与NM38检测肺炎克雷伯菌对碳青霉烯类抗菌药物的性能均可靠,但应重视AES的修正或预警作用。

Objective To evaluate the reliabilities of VITEK 2-Compact GN13 and MicroScan WalkAway 96 Plus NM38 to determine the drug susceptibility of carbapenems against Klebsiella pneumoniae.Methods GN13,NM38 and broth micro-dilution method were used to determine the drug susceptibility of carbapenems to 168 isolates of Klebsiella pneumoniae which were isolated from Huangshan People's Hospital from January 2016 to August 2017.The determination results of GN13 and NM38 were judged by broth micro-dilution method as gold standard.A modified carbapenem inactivation method(mCIM)was used to determine carbapenems and to analyze their reliabilities of advanced expert system(AES)as a predictor or early warning indicator for carbapenem production.Results Using broth micro-dilution method as gold standard,GN13 and NM38 classification categorical agreement(CA)was>90%.Minor errors(MIE)and major errors(ME)for imipenem were reduced by 0.6%,and MIE for ertapenem was increased by 0.6%without very major errors(VME)after AES modification.The MIE,ME and VME determined by NM38 for imipenem accounted for 1.19%,1.19%and 2.97%,and MIE,ME and VME for ertapenem accounted for 3.6%,0.0%and 0.6%.The mCIM phenotype determination showed that the positive rate of carbapenems was 27.4%(46/168),and the positive rates of carbapenems after GN13 AES modification and NM38 prediction were 31.0%and 30.4%,respectively.Compared with mCIM,there was no statistical significance(P>0.05).Conclusions The results of GN13 and NM38 are reliable in determining the drug susceptibility of carbapenems against Klebsiella pneumoniae.However,attention should be paid to the modification or early warning of AES.