检验医学 ›› 2013, Vol. 28 ›› Issue (1): 11-16.DOI: 10.3969/j.issn.1673-8640.2013.01.003

• 临床应用研究.论著 • 上一篇    下一篇

肺炎支原体23SrRNA基因突变位点与耐药表型的分析

  

  1. 西安医学院附属医院,陕西 西安 710077
  • 出版日期:2013-01-30 发布日期:2013-01-10
  • 作者简介:叶芸,女,1974年生,硕士,副主任技师,主要从事免疫学及分子生物学研究。
  • 基金资助:

    西安医学院附属医院科研计划项目(XYFY-09-20)

Analysis on Mycoplasma pneumonia 23SrRNA gene mutation site and drug resistance phenotype

  1. The Affiliated Hospital of Xi′an Medical College,Shanxi Xi′an 710077,China
  • Online:2013-01-30 Published:2013-01-10

摘要: 目的 了解本地区社区呼吸道感染肺炎支原体(Mycoplasma pneumoniae,Mp)感染状况,探讨肺炎支原体对大环内酯类抗菌药物的耐药分子机制,并分析肺炎支原体耐药菌株23SrRNA基因突变位点与耐药表型之间的关系。 方法 对400例社区获得性呼吸道感染患儿咽拭子标本进行分离培养,应用巢式聚合酶链反应(PCR)对临床分离株进行分子鉴定;通过体外药物敏感试验测定Mp临床分离株对大环内酯类抗菌药物的最小抑菌浓度(MIC),并筛选出耐药株;检测耐药株23SrRNA基因序列,并与标准菌株M129基因序列对比分析,分析突变位点与耐药表型的关系。 结果 400例咽拭子标本中分离Mp 50株。其中敏感株32株,耐药株18株。18株耐药株分别出现A2063G、A2064G、A2067G 位点突变。A2063G表现出对14元环大环内酯类抗菌药的耐药,A2064G表现为对14、16元环大环内酯类抗菌药的耐药,A2067G表现出对交沙霉素耐药。 结论 Mp对大环内酯类抗菌药物耐药现象严重,23SrRNA基因位点突变是耐药性产生的主要机制。通过对23SrRNA基因突变位点与耐药表型的分析研究,初步了解临床肺炎支原体耐药现状,并且为抗菌药物的合理选择和应用提供理论指导。

关键词: 肺炎支原体, 基因突变, 大环内酯类, 微生物敏感试验

Abstract: Objective To investigate the infection situation of Mycoplasma pneumonia(Mp)in patients with community-acquired respiratory tract infection and the molecular drug resistance mechanisms of macrolide,and to analyze the relationship between 23SrRNA gene mutation site of isolates resistant to Mp and drug resistance phenotype.   Methods A total of 400 throat swab specimens of community-acquired respiratory tract infection were cultured to isolate Mp,the clinical isolates were identified by nested polymerase chain reaction,and the in vitro antibiotic sensitivity test was performed for identifying macrolide-resistant isolates through the minimal inhibitory concentration(MIC).The sequences of macrolide-resistant 23SrRNA gene were detected. The sequences were compared to the corresponding sequences of M129. The relationship between mutation site and drug resistance phenotype was analyzed.  Results A total of 50 Mp were isolated from 400 throat swab specimens.Of the 50 isolates,32 isolates were susceptible to macrolide,and 18 isolates were resistant to macrolide.The 18 clinical isolates appeared mutation A2063G,A2064G and A2067G,separately. A2063G showed 14 ring macrolide resistance.A2064G showed 14 and 16 ring macrolide resistances. A2067G showed josamycin resistance.  Conclusions Mp to macrolide resistance is serious,and the mutation of 23SrRNA gene is a predominant mechanism that contributes to the macrolide resistance. Through the analysis of 23SrRNA gene mutation site and drug resistance phenotype,the clinical Mp drug resistance situation is obtained. The theoretical guidance for reasonable selection and application of antibiotics is provided.

Key words: Mycoplasma pneumonia, Gene mutation, Macrolide, Microbial sensitivity test