神经外科患者感染肺炎克雷伯菌耐药株parC基因变异分析及抗生素合理选用  

Analysis of mutations of the parC gene of Klebsiella pneumoniae infecting Neurology patients and the rational selection of antibiotics

作　　者：胡成旺[1] 蔡中立[2] 张忠[3] 

机构地区：[1]南阳医学高等专科学校第一附属医院神经外科,河南南阳473000 [2]南阳医学高等专科学校第一附属医院胸外科,河南南阳473000 [3]首都医科大学附属北京天坛医院神经外科,北京100050

出　　处：《中国病原生物学杂志》2015年第7期644-647,共4页Journal of Pathogen Biology

摘　　要：目的研究神经外科患者感染肺炎克雷伯菌耐药株parC基因变异情况,分析菌株耐药性,以指导临床治疗的合理用药。方法收集2014年3月至2015年1月间神经外科院内感染患者的痰液等标本,作细菌培养后采用VITEK-2Compact全自动细菌鉴定仪进行鉴定,采用K-B纸片法检测肺炎克雷伯菌对喹诺酮类抗菌药物耐药性。提取parC基因,电泳鉴定后测序,分析其变异情况。结果药敏试验显示,分离株肺炎克雷伯菌对诺氟沙星、氧氟沙星、培氟沙星、左氧氟沙星、依诺沙星以及环丙沙星的耐药率分别为88.57%、82.86%、60.00%、51.43%、40.00%和32.86%,对加替沙星敏感。PCR扩增肺炎克雷伯菌parC基因片段大小为423bp。基因测序后与标准株对比,实验株80位氨基酸密码子由AGC突变为ATC,相应氨基酸由丝氨酸突变为异亮氨酸;实验株91位氨基酸密码子由AAT突变为GAT,相应氨基酸由天冬酰胺突变为天冬氨酸。结论肺炎克雷伯菌的耐药性产生与其parC基因位点突变有关。神经外科患者感染肺炎克雷伯菌的药物治疗应首选加替沙星。Objective Mutations in the parC gene of Klebsiella pneumoniae infecting Neurology patients were studied and the drug resistance of K.pneumoniae was analyzed to guide the rational use of drugs in clinical treatment. Methods Sputum and other specimens were collected from Neurosurgery patients with a nosocomial infection from March 2014 to January 2015.Bacteria were identified with the VITEK-2Compact and then cultured.The drug resistance of K.pneumoniae to quinolone was tested using the K-B method.The parC gene was extracted and sequenced using electrophoresis to analyze its mutations. Results The results of drug resistance testing indicated that K.pneumoniaeresistance to norfloxacin was 88.57%,its resistance to ofloxacin was 82.86%,its resistance to pefloxacin was 60.00%,its resistance to levofloxacin was 51.43%,its resistance to enoxacin was 40.00%,and its resistance to ciprofloxacin was 32.86%,but it was sensitive to gatifloxacin.Results of PCR amplification revealed that the parC gene of K.pneumoniae was 423 bp in length.After gene sequencing,isolates were compared to standard strains.The amino acid at codon 80 in the tested strain was mutated from AGC to ATC,corresponding to an amino acid mutation from Ser to Ile.The amino acid at codon 91 was mutated from AAT→GAT,corresponding to an amino acid mutation from Asn→Asp. Conclusion The drug resistance of K.pneumoniae was related to mutations in its parC gene.Gatifloxacin should be the drug of choice when treating an infection with K.pneumoniaein Neurology patients.

关 键 词：神经外科 肺炎克雷伯菌 PARC基因 抗生素 

分 类 号：R511[医药卫生—内科学]