摘要
背景大环内酯类抗生素是治疗儿童和青少年肺炎支原体（MP）相关呼吸道感染的首选药物,近年来,大环内酯类抗生素耐药MP逐渐增多.目的 了解2011年北京地区儿童MP耐药情况并探讨其耐药机制.方法 采集2011年首都医科大学附属北京友谊医院儿科和首都医科大学附属北京朝阳医院儿科收治的205例MP感染患儿呼吸道咽拭子标本,进行MP培养与药敏试验,采用巢式PCR扩增法鉴定MP耐药位点.结果 采集的205株MP中,MP培养阳性59株,阳性率为28.8%;23S rRNA巢式PCR扩增阳性122株,阳性率为59.5%,其中敏感株19例,耐药株103例,耐药率为84.4%,均为23S rRNA结构域Ⅴ区A2063G点突变.59株培养阳性的MP共在实验室储存了26株,药敏试验结果显示其中2株为敏感株,红霉素最小抑菌浓度（MIC）≤0.01 mg/L;剩余24株为耐药株,红霉素MIC为32.00～256.00 mg/L,红霉素耐药率为92.3%.26株临床分离株均无23S rRNA结构域Ⅱ区基因改变,均存在23S rRNA结构域Ⅴ区A2063G点突变.1株敏感株和MP标准株FH发现核糖体蛋白L4的162位点C-A和430位点A-G点突变,1株敏感株发现209位点A-T点突变;26株临床分离株均出现核糖体蛋白L22的508位点T-C点突变.结论 2011年北京地区儿童MP感染率较高,对大环内酯类抗生素耐药现象严重,其耐药机制主要为23S rRNA结构域Ⅴ区点突变,而核糖体蛋白L4、L22点突变及其引起的部分氨基酸变化的作用还有待进一步研究.
Backgrounds Macrolides （MLs） are considered as the first choice for. the treatment of Mycoplasma pneumoniae （MP） - associated respiratory diseases in children and adolescents, but Macrolide - resistance to MP has increased gradually in recent years. Objective To investigate prevalent condition of the Macrolide - resistant MP in Beijing Distrect in 2011 and its molecular mechanism. Methods The throat swab specimens of 205 MP children admitted to Pediatric Departments of Beijing Friendship Hospital and Chaoyang Hospital in the year of 2011 were collected and cultured, and drug sensitivity test performed. Nested PCR amplification method （nPCR） was used to identify MP resistance loci. Results In collected 205 MP strains, there were 59 strains of MP cuhure positive （28. 8% ） ; 122 strains of 23S rRNA nPCR positive （59. 5% ）, including 19 sensitive strains, 103 drug- resistance strains, with a rate of 84.4%, which were all A2063G point mutations in 23S rRNA V domain. Totally 26 positive MP strains were established, including 2 sensitive strains [ erythromycin minimum inhibitory con- centration （MIC） ~〈0. 01 mg/L~, 24 drug -resistance strains （MIC = 32. 00 -256. 00 mg/L）, with a drug - resistance rate of 92. 3%. And 26 isolates had no gene changes in 23S rRNA II domain and had A2063G point mutations in 23S rRNA V do- main. One sensitive strain and MP standard strain FH had point mutations at 162 loci C - A and 430 loci A - G of ribosomal pro- tein IA, 1 sensitive strain had point mutation of 209 loci A - T ; 26 isolates all had 508 loci T - C point mutation of ribosomal protein L22. Conclusion MP is widely prevalent in children and its resistance to MLs is serious. Point mutation in domain V of 23S rRNA is the main molecular mechanism. But point mutation in ribosomal protein and the change of amino acid remains un- clear, which requires further investigation.
出处
《中国全科医学》
CAS
CSCD
北大核心
2013年第32期3778-3782,共5页
Chinese General Practice
基金
北京市科学技术委员会资助项目:北京地区儿童重症肺炎支原体肺炎临床特征和控制方案研究(Z131100004013029)
首都医科大学附属北京友谊医院院级课题:肺炎支原体及耐药支原体监测平台的建设(BJYYYY2011-31)
关键词
支原体
肺炎
大环内酯类
抗药性
微生物
药理作用分子作用机制
Mycoplasma pneumoniae
Macrolides
Drug resistance, microbial
Molecular mechanisms of pharmacological action
