肺炎克雷伯菌gyrA和parC基因喹诺酮耐药决定区突变与环丙沙星耐药相关性研究  

Correlation between mutation in quinolone resistance-determining region of gyrA and parC genes in Klebsiella pneumoniae isolates and ciprofloxacin resistance

作　　者：何俊英 胡晓玲 孙爱华[2] 

机构地区：[1]衢州市妇幼保健院,浙江衢州324000 [2]浙江医学高等专科学校,浙江杭州310053

出　　处：《中国卫生检验杂志》2014年第8期1191-1193,1198,共4页Chinese Journal of Health Laboratory Technology

基　　金：浙江省自然科学基金项目(LY12H19002);浙江省医药卫生科技计划项目(2011KYA005)

摘　　要：目的研究肺炎克雷伯菌临床菌株gyrA和parC基因喹诺酮耐药决定区(QRDR)突变与环丙沙星耐药的相关性。方法采用琼脂稀释法检测124株临床菌株对环丙沙星的最小抑菌浓度(MIC),K-B法检测临床菌株对其他13种抗菌药物的耐药性,测序分析50株临床菌株gyrA和parC基因QRDR喹诺酮耐药决定区。结果 124株临床菌株对环丙沙星耐药和敏感的分别有56株和68株。未见亚胺培南和美洛培南耐药菌株,氨苄西林和哌拉西林总耐药率达99.2%和96.0%。所有敏感株对环丙沙星的MICs≤1mg/L,耐药株对环丙沙星的MICs≥4 mg/L。环丙沙星耐药株gyrA基因突变发生率明显高于敏感株(P<0.05),且Ser83突变发生与MICs大小有关。环丙沙星耐药株parC基因Ser80突变发生率明显高于敏感株(P<0.01),parC基因Ser80突变与耐药程度密切相关。结论亚胺培南和美洛培南可推荐用于本地区肺炎克雷伯菌感染的治疗,gyrA和parC基因突变在环丙沙星耐药中起重要作用。Objective To analyze the correlation between mutations in the quinolone-resistance-determining-region（ QRDR） of gyrA and parC and ciprofloxacin resistance in K. pneumoniae isolates. Methods The MICs of ciprofloxacin in 124 Klebsiella pneumoniae isolates were determined by agar dilution method. The susceptibility to other 13 antibiotics were determined by K-B method. PCR and DNA sequencing were conducted to analyze the QRDR associated genes gyrA and parC in 50 Klebsiella pneumoniae isolates. Results In the 124 Klebsiella pneumoniae isolates,56 isoaltes were resistant to ciprofloxacin, while 68 isolates were susceptive to ciprofloxacin. All isolates were susceptive to imipenem and meropenem,the resistance rate of 124 Klebsiella pneumoniae isolates were 99. 2% and 96. 0% to ampicillin and piperacillin,respectively. The MICs of ciprofloxacin was below 1 mg/ L in ciprofloxacin-susceptive isoaltes,while that was above 4 mg/ L in ciprofloxacin-resistance isolates. The mutation rates of Ser83 or/ and Asp87 in ciprofloxacin-resistance isolates were obviously higher than those in ciprofloxacin-susceptive isolates,respectively（ P〈 0. 05）,and ciprofloxacin MICs were closely related with Ser83 mutations. The mutation rate of Ser80 in ciprofloxacin-resistance was obviously higher than that in ciprofloxacin-susceptive isolates,（ P〈 0. 01）,and Ser80 mutation of parC gene was closely related to the degree of drug resistance. Conclusion Imipenem and meropenem can be used for routine therapy of Klebsiella pneumoniae infection. Mutations in gyrA and parC genes play an important role in the development of ciprofloxacin resistance in Klebsiella pneumoniae.

关 键 词：肺炎克雷伯菌 GYRA和PARC基因 突变/耐药性 序列分析 

分 类 号：R378.14[医药卫生—病原生物学]