一株高度耐碳青霉烯类药物的肺炎克雷伯菌耐药性研究

Detection of a IMP-4 type metal beta lactamase-producing Klebsiella pneumonia highly resistant to carbapenem drugs

目的了解从临床患者病灶中分离到的一株高度耐碳青霉烯类药物的肺炎克雷伯菌的耐药机制。方法药敏试验采用微量肉汤稀释法与etest法,碳青霉烯酶表型检测采用改良Hodge试验和双纸片增效法,其基因型测定采用多组碳青霉烯耐药相关基因引物PCR并测序,由北京大学临床药理研究所负责完成。结果药敏测试结果除对阿米卡星和多粘菌素敏感外,对临床常用亚胺培南(mic>32ug/ml)、美罗培南(mic>32ug/ml)、一至四代的头孢菌素类、硅诺酮类以及庆大霉素、头孢西丁、氨曲南、复方新诺明、四环素、美满霉素、氨苄西林、氨苄西林/舒巴坦、哌拉西林、哌拉西林/他唑巴坦、阿莫西林/棒酸、头孢哌酮/舒巴坦,均表现为耐药。碳青霉烯酶表型检测试验改良Hodge试验阳性,双纸片增效法阳性,碳青霉烯耐药基因为blaIMP-4。结论产IMP-4型金属β内酰胺酶的肺炎克雷伯菌已证实在我院存在,其泛耐药性,应引起我们足够的重视。

Objective To understand the resistant mechanism of a Klebsiella pneumonia strain highly resistant to to carbapenem drugs.Methods Both broth microdilution and Etest method were usef for antimicrobial susceptibility test of Klebsiella pneumonia to carbapenemases,modified Hodge test and double disk synergy method were uxed for phenotype detection and multiple groups of carbapenem resistance related gene primers PCR and sequencing was used for genotype determination with assistance of Beijing University Institule of Clinical Pharmacology.Results Klebsiella pneumonia resistant to on commonly used clinical imipenem（mic32ug/ml）,meropenem（mic32ug/ml）,the first to fourth generation of cephalosporins,quinolone and gentamicin,cefoxitin,aztreonam trimethoprim/sulphamethoxazole,telracycline minocycline,ampicillin,ampicillin/sulbactam,piperacillin,piperacillin/tazobactam,amoxicillin/clavulanic acid,cefoperazone/sulbactam,but sensitive to amikacin and polymyxin B.carbapenem resistance gene was blaIMP-4.Conclusion IMP-4 type metal lactamase Klebsiella pneumonia resistant to most common antibacterials has been detected in this hospital and attention be paid to monitoring and treatment..