呼吸道感染患者肺炎克雷伯菌gyrA基因和parC基因突变情况及其耐药机制分析  

Analysis of mutations of the gyrA gene and parC gene of Klebsiella pneumoniae infecting patients with a respiratory tract infection and analysis of the mechanisms of drug resistance

作　　者：张明华[1] 杨钢[1] 李晶[2] 

机构地区：[1]湖北省武汉市中心医院呼吸内科,湖北武汉430014 [2]天津医科大学肿瘤医院检验科、国家肿瘤临床医学研究中心、天津市肿瘤防治重点实验室,天津300060

出　　处：《中国病原生物学杂志》2015年第1期65-68,共4页Journal of Pathogen Biology

摘　　要：目的通过药敏试验探究肺炎克雷伯菌的耐药情况,分析其gyrA基因和parC基因突变与其耐药性的相关性,进而为呼吸道感染肺炎克雷伯菌的临床治疗提供指导。方法从呼吸道感染患者体内分离肺炎克雷伯菌并进行鉴定,然后测定其对各种抗生素的耐药情况,并通过基因测序研究gyrA基因和parC基因的突变情况与其耐药性关系。结果药敏试验结果显示,肺炎克雷伯菌对诺氟沙星、氧氟沙星、左氧氟沙星、环丙沙星、加雷沙星、加替沙星和莫西沙星的耐药率分别为45.65%、39.13%、30.43%、27.17%、13.30%、14.13%和10.87%。通过PCR方法成功地对gyrA和parC基因进行了扩增,并从电泳图得出gyrA基因分子量大小为449bp、parC基因分子量大小为319bp。通过基因测序比对发现,gyrA基因的83位、87位和parC基因的80位、91位都有不同类型的突变,这些突变与肺炎克雷伯菌的耐药性密切相关。结论 gyrA基因和parC基因突变与肺炎克雷伯菌的耐药性密切相关,但是若要彻底解决其耐药性问题,应从源头上控制抗生素的合理选用,从而更好地指导呼吸道感染的临床治疗。Objectives Drug susceptibility testing was used to explore the drug resistance of Klebsiella pneumoniae and to analyze the correlation between mutations of the gyrA gene and parC gene and drug resistance in order to guide the clinical treatment of K.pneumoniae infecting the respiratory tract. Methods K.pneumoniae was isolated from patients with a respiratory tract infection and identified.Its resistance to various antibiotics was then determined.Gene sequencing was used to study the correlation between mutations of the gyrA gene and parC gene and the drug resistance of K.pneumoniae. Results Drug sensitivity testing indicated that K.pneumoniae had 100.0% resistance to cefotaxime,ampicillin,cefepime,and cefuroxime,80.0% resistance to gentamycin,60.0% resistance to piperacillin,and 0.0% resistance to amikacin.The gyrA and parC genes were successfully amplified with PCR,and electrophoregrams indicated that the gyrA gene was 449 bp in size and that the parC gene was 319 bp in size.Gene sequencing and comparison of sequences revealed that there were different types of mutations at exon 83 and exon 87 of the gyrA gene and at exon 80 and exon 91 of the parC gene.These mutations were closely associated with the drug resistance of K.pneumoniae. Conclusion Amikacin can be the drug of choice to treat K.pneumoniaeinfecting patients with a respiratory tract infection.Mutations of the gyrA gene and parC gene were closely associated with the drug resistance of K.pneumoniae.To completely resolve the problem of that resistance,antibiotics should be chosen rationally to control that infection from the start,thus facilitating better clinical treatment of respiratory tract infections

关 键 词：呼吸道感染 肺炎克雷伯菌 GYRA基因 PARC基因 耐药率 

分 类 号：R378.99[医药卫生—病原生物学]