携带blaCTX-M-55基因的大肠埃希菌氨基糖苷类耐药相关元件分析

发布时间：2018-05-31 13:14

本文选题：大肠埃希菌 + 耐药　；参考：《中华医院感染学杂志》2017年11期

【摘要】：目的调查携带blaCTX-M-55基因的大肠埃希菌中氨基糖苷类耐药相关元件的携带状况,以及了解本组菌株间的亲缘关系。方法收集2015年1-12月宁波大学医学院附属医院住院患者痰液标本中分离30株携带blaCTX-M-55基因的大肠埃希菌,用K-B法测定9种抗菌药物的敏感性,采用聚合酶链反应(PCR)及序列分析的方法分析7种氨基糖苷类修饰酶基因,2种16SrRNA甲基化酶基因,7种可移动遗传元件遗传标记,阳性耐药基因测序后直接作BLAST比对,耐药基因检测结果作样本聚类分析(UPGMA法)。结果 30株携带blaCTXM-55基因的大肠埃希菌对头孢类、氨基糖苷类、喹诺酮类抗菌药物均耐药,但对碳青霉烯类抗菌药物均为敏感;30株菌均检出氨基糖苷类修饰酶基因和可移动遗传元件遗传标记,另有5株检出16SrRNA甲基化酶基因,30株菌共检出5种氨基糖苷类修饰酶基因、1种16SrRNA甲基化酶基因、7种可移动遗传元件遗传标记,且阳性率较高;样本聚类分析显示,该组菌株有明显的聚集性,有6个克隆传播。结论本组30株携带blaCTX-M-55基因的大肠埃希菌同时携带了氨基糖苷类修饰酶基因、16SrRNA甲基化酶基因和可移动遗传元件遗传标记,是对头孢类和氨基糖苷类产生耐药的重要原因;本组菌检出的6个克隆高度疑似医院感染,同一克隆菌株携带相同基因。
[Abstract]:Objective to investigate the carrying status of aminoglycoside resistance related elements in Escherichia coli carrying blaCTX-M-55 gene and to understand the relationship between these strains. Methods from January to December 2015, 30 strains of Escherichia coli carrying blaCTX-M-55 gene were isolated from the sputum of hospitalized patients in the affiliated Hospital of Ningbo University Medical College, and the sensitivity of 9 antimicrobial agents was determined by K-B method. Polymerase chain reaction (PCR) and sequence analysis were used to analyze 7 aminoglycoside modified enzyme genes, 2 16SrRNA methylase genes and 7 transportable genetic element genetic markers. The positive drug resistance genes were sequenced and compared with BLAST directly. The results of detection of drug resistance genes were analyzed by UPGMA method. Results 30 strains of Escherichia coli carrying blaCTXM-55 gene were resistant to cephalosporins, aminoglycosides and quinolones. However, the aminoglycoside modifying enzyme gene and the genetic marker of removable genetic elements were detected in 30 strains of carbapenem antibiotics. In addition, 5 16SrRNA methylase genes and 1 16SrRNA methylase gene were detected in 5 strains and 7 transportable genetic element genetic markers were detected, and the positive rate was high. The strain showed obvious aggregation and 6 clones were transmitted. Conclusion the 30 strains of Escherichia coli carrying blaCTX-M-55 gene carry 16s rRNA methylase gene of aminoglycoside modifying enzyme and the genetic marker of removable genetic elements, which is an important reason for drug resistance to cephalosporins and aminoglycosides. The 6 clones were highly suspected of nosocomial infection, and the same cloned strains carried the same gene.
【作者单位】：宁波大学医学院附属医院普外科;宁波大学医学院附属医院呼吸科;宁波大学医学院附属医院细菌室;
【基金】：宁波市自然科学基金资助项目(2016A610132)
【分类号】：R446.5

【相似文献】