肺炎链球菌毒力基因表达差异性及对大环内酯类耐药性分析  

Differences of virulence gene expression in Streptococcus pneumoniae and analysis of resistance to macrolide

作　　者：熊晓顺 林祥芳 张楠[1] 魏丹丹[3] XIONG Xiao-shun;LIN Xiang-fang;ZHANG Nan;WEI Dan-dan(The Second Affiliated Hospital of Nanchang University,Nan chang,Jiang xi 330006,China)

机构地区：[1]南昌大学第二附属医院检验科,江西南昌330006 [2]扬州市第一人民医院检验科,江苏扬州225001 [3]南昌大学第一附属医院检验科,江西南昌330006

出　　处：《中华医院感染学杂志》2020年第5期641-647,共7页Chinese Journal of Nosocomiology

基　　金：国家自然科学基金资助项目(81560323);江西省教育厅青年基金资助项目(GJJ160233);江西省卫生计生委科技计划基金资助项目(20195210)。

摘　　要：目的探讨临床分离各表型肺炎链球菌毒力基因表达的差异性并分析其对青霉素和大环内酯类抗菌药物的耐药性.方法收集2012年12月-2016年12月不同来源的肺炎链球菌111株,分为侵袭性组和非侵袭性组,采用荚膜肿胀实验进行血清学分型,聚合酶链反应(PCR)和荧光定量PCR检测psaA、ply、lytA、cbpA、nanA毒力基因,最低抑菌浓度(MIC)法检测药物敏感性并用PCR检测相关耐药基因(PBP1A、PBP2B、PBP2X,er-mB、mefA).结果111株肺炎链球菌共检出24个血清型/群,流行血清型为:19F、19A、14、23F、6A、6B.所有菌株5个毒力基因的携带率基本均接近100%;侵袭性菌株nanA、lytA、psaA、ply 4个毒力基因在转录水平高于非侵袭性菌株,此外19F和6A/B血清型中侵袭性菌株这4个毒力基因转录水平也高于非侵袭性组;nanA、psaA、cbpA和ply在3型中的转录水平高于其他血清型.血液与痰液标本来源的肺炎链球菌毒力基因转录水平有一定差异但无统计学意义,脑脊液来源与血液,痰液比较,转录水平增高;脑膜炎肺炎链球菌青霉素非敏感率为70.00%(7/10),非脑膜炎肺炎链球菌青霉素非敏感率为18.81%(19/101),90.09%(100/111)菌株同时对红霉素和克林霉素耐药,主要携带ermB基因.结论常见5种毒力基因在肺炎链球菌中普遍存在,但不同致病类型、不同血清型和不同来源菌株基因表达水平存在差异,侵袭性3型和脑脊液来源的菌株毒力较强,且该地区肺炎链球菌对青霉素、红霉素和克林霉素耐药率较高,尤其是脑膜炎肺炎链球菌,应引起临床重视.OBJECTIVE To investigate the differences in virulence gene expression of clinically isolated phenotypes of Streptococcus pneumoniae and to analyze their resistance to penicillin and macrolide antibiotics. METHODS From Dec. 2012 to Dec. 2016, 111 strains of S.pneumoniae from different sources were collected and divided into invasive and non-invasive groups. Capsid swelling test was used for serological typing, polymerase chain reaction(PCR) and fluorescence quantitative PCR were used to detect the psaA, ply, lytA, cbpA, and nanA virulence genes. The minimum inhibitory concentration(MIC) method was used to detect drug susceptibility and PCR was used to detect relevant drug resistance genes(PBP1A, PBP2B, PBP2X, ermB, and mefA). RESULTS A total of 24 serotypes/groups were detected in 111 strains of S. pneumoniae, and the prevalence serotypes were: 19 F, 19 A, 14, 23 F, 6 A, 6 B. The carrier rates of 5 virulence genes in all strains were basially close to 100%. The transcriptional level of four virulence genes(nanA, lytA, psaA, and ply) in invasive strains were significantly higher than that in non-invasive strains, which is same in the strains of 19 F and 6 A/B serotypes. The transcription levels of nanA, psaA, cbpA, and ply in type 3 were higher than those in other serotypes. The transcriptional level of virulence genes of S. pneumoniae derived from blood and sputum specimens at showed a certain difference but not significant. Compared with blood and sputum, the cerebrospinal fluid source had higher transcription levels. Meningitis Streptococcus pneumoniae non-sensitivity rate was 70.00%(7/10), non-meningitis ones penicillin non-sensitivity rate was 18.81%(19/101), and 90.09%(100/111) of strains were simultaneously resistant to erythromycin and clindamycin, mainly carrying the ermB gene. CONCLUSION Five common virulence genes were ubiquitous in S.pneumoniae but virulence gene expression level of different pathopoiesis types, different serotypes and strains from different sources were different. Aggressive type 3 and

关 键 词：肺炎链球菌 血清型 毒力基因 转录水平 耐药率 

分 类 号：R378[医药卫生—病原生物学]