产KPC-71肺炎克雷伯菌对头孢他啶/阿维巴坦耐药机制研究  

Mechanism of KPC-71 producing Klebsiella pneumoniae resistance to Cefotaxime/Avibactam

作　　者：卫叶林[1] 王佳庆 朱永泽[3] 张淑琦 WEI Yelin;WANG Jiaqing;ZHU Yongze;ZHANG Shuqi(Department of Laboratory Medicine,the First People's Hospital of Xiaoshan District,Hangzhou City,Hangzhou 311200,China;不详)

机构地区：[1]杭州市萧山区第一人民医院检验科,311200 [2]绍兴市中心医院医共体总院检验科 [3]浙江省人民医院检验中心 [4]海宁市中心医院检验科

出　　处：《浙江医学》2025年第6期619-624,共6页Zhejiang Medical Journal

摘　　要：目的探讨产肺炎克雷伯碳青霉烯酶(KPC)71型(KPC-71)肺炎克雷伯菌(KP)对头孢他啶/阿维巴坦耐药的分子机制。方法采用侧流免疫层析法对分离自2024年杭州市萧山区第一人民医院收治的同一肺部感染患者的2株KP菌株(KP536与KP877)进行碳青霉烯酶酶型检测;采用微量肉汤稀释法对菌株进行药物最低抑菌浓度检测;利用聚合酶链式反应(PCR)对菌株携带的blaKPC基因进行扩增并测序,结果用SnapGene软件进行分析;通过全基因组测序明确菌株序列型别及耐药基因;通过生长曲线仪检测菌株生长特点。结果KP536与KP877相隔70 d先后分离自患者痰液标本。酶型结果显示KP536与KP877菌株均产KPC,药物敏感实验结果显示两个菌株具有不同药敏表型:KP536菌株对头孢他啶/阿维巴坦敏感,对亚胺培南、美罗培南耐药;而KP877菌株对头孢他啶/阿维巴坦耐药,对亚胺培南、美罗培南敏感;PCR及测序结果显示KP536与KP877分别携带bla_(KPC-2)与bla_(KPC-71)基因。相比bla_(KPC-2),bla_(KPC-71)在542至545位插入了3个核苷酸(ATC),导致在Ambler182和183位之间插入1个丝氨酸。全基因组测序结果显示,2株KP菌株均为ST11型,且携带多个耐药基因,包括bla_(KPC)、bla_(LAP-2)、bla_(SHV-187)、bla_(TEM-1)、rm-tB1、qnrS1、sul2、tetA、dfrA14、fosA6等。结论KP携带的bla_(KPC-71)由bla_(KPC-2)突变而来,可导致KP对头孢他啶/阿维巴坦耐药而恢复对碳青霉类抗菌药物敏感性。临床应注意在使用头孢他啶/阿维巴坦治疗KP时出现耐药问题。Objective To clarify the molecular mechanism of Klebsiella pneumoniae carbapenemase 71(KPC-71)producing Klebsiella pneumoniae(KP)resistance to cefotaxime/avibactam.Methods Two strains of KP(KP536 and KP877)isolated from the same clinical patient were subjected to carbapenemase type detection using lateral flow immunoassay;the minimum inhibitory concentration of the bacterial strain was detected using the micro broth dilution method;The blaKPC gene carried by the strain was amplified and sequenced using polymerase chain reaction(PCR),and the results were analyzed using SnapGene software;strain sequence types and resistance genes were determined via whole genome sequencing;the growth characteristics of bacterial strains were detected using a growth curve analyzer.Results KP536 and KP877 were successively separated from sputum samples of patients 70 days apart.The enzyme typing results showed that both KP536 and KP877 strains produced KPC.The drug sensitivity results showed that the two strains had inconsistent drug sensitivity phenotypes:KP536 strain was sensitive to cefotaxime/avibactam,but resistant to imipenem and meropenem;KP877 strain was resistant to cefotaxime/avibactam but sensitive to imipenem and meropenem;PCR sequencing results showed that KP536 and KP877 carried the bla_(KPC-2) and bla_(KPC-71) genes,respectively.Compared to bla_(KPC-2),bla_(KPC-71) inserted three nucleotides(ATC)between positions 542 and 545,resulting in the insertion of a serine between positions Ambler 182 and 183.The whole genome sequencing results showed that two strains of KP were ST11 type,carrying multiple resistance genes,including bla_(KPC),bla_(LAP-2),bla_(SHV-187),bla_(TEM-1),rmtB1,qnrS1,sul2,tetA,dfrA14,fosA6,etc.Conclusion The bla_(KPC-71) carried by KP is mutated from bla_(KPC-2),which can lead to KP resistance to cefotaxime/avibactam and restore sensitivity to carbapenem antibiotics.Clinical attention should be paid to the issue of drug resistance when using cefotaxime/avibactam to treat KP.

关 键 词：肺炎克雷伯菌 碳青霉烯酶 耐药机制 头孢他啶/阿维巴坦耐药 

分 类 号：R44[医药卫生—诊断学]