猩红热患儿A族链球菌emm基因分型及地域与毒力基因分布相关研究

Relationship among emm gene typing,regional and virulence gene distribution of group A Streptococcus strains isolated from children with scarlet fever

目的探讨猩红热儿童分离来源的A族链球菌(GAS)emm分型、地域与毒力基因分布的相关性。方法采集北京和上海地区猩红热患儿标本进行GAS分离鉴定,应用聚合酶链式反应(PCR)方法检测emm基因型以及13种毒力基因(speA、speB、speC、speF、speG、speH、speI、speJ、speK、speL、speM、ssa和smeZ)携带情况,分析GAS菌株毒力基因分布与地域、emm基因型的关系。结果114株GAS分离株中,emm1.0型60株,emm12.0型54株;52株分离自北京(emm1.0型31株,emm12.0型21株),62株分离自上海(emm1.0型29株,emm12.0型33株)。speA、speC、speG、speH、speI、speJ、speK、ssa和smeZ基因携带率分别为52.6%、76.3%、80.7%、43.9%、55.3%、57.0%、75.4%、97.4%、93.0%,speB和speF携带率均为98.2%,未检出speL、speM基因。北京地区emm1.0型与emm12.0 GAS菌株speA、speH、speI和speJ基因携带率比较,上海地区emm1.0型与emm12.0 GAS菌株speA、speH、speI、speJ和speK基因携带率比较,差异均有统计学意义(均P<0.05)。emm1.0型GAS菌株speC、speH、speJ和speK基因携带率北京与上海两地区比较,差异均有统计学意义(均P<0.05),emm12.0型GAS菌株speC、speH、speI、speJ和speK基因北京与上海两地区比较,差异均有统计学意义(均P<0.05)。结论GAS菌株毒力基因的分布状态因emm基因分型及地域不同存在差异。

Objective To investigate the relationship between emm typing,regional and virulence gene distribution of group A Streptococcus(GAS)isolated from children with scarlet fever.Methods Specimens from children with scarlet fever in Beijing and Shanghai were collected for GAS isolation and identification,emm genotype and carrying status of 13 kinds of virulence genes(speA,speB,speC,speF,speG,speH,speI,speJ,speK,speL,speM,ssa and smeZ)were detected by polymerase chain reaction(PCR),relationship between distribution of virulence gene and region as well as emm genotype of GAS strains was analyzed.Results Among 114 GAS strains,60 were emm1.0 and 54 were emm12.0;52 strains were isolated from Beijing(31 strains were emm1.0 and 21 were emm12.0),and 62 strains were from Shanghai(29 were emm1.0 and 33 were emm12.0).The carrying rates of speA,speC,speG,speH,speI,speJ,speK,ssa and smeZ were 52.6%,76.3%,80.7%,43.9%,55.3%,57.0%,75.4%,97.4%,and 93.0%respectively,carrying rates of speB and speF were both 98.2%,speL and speM genes were not found.There were significant difference in carrying rates of speA,speH,speI and speJ genes of emm1.0 and emm12.0 GAS strains in Beijing as well as speA,speH,speI,speJ and speK genes of emm1.0 and emm12.0 GAS in Shanghai(all P<0.05).Carrying rates of speC,speH,speJ and speK of emm1.0 GAS strain,as well as carrying rates of speC,speH,speI,speJ and speK of emm12.0 strain between Beijing and Shanghai were all significant(all P<0.05).Conclusion Distribution of virulence genes of GAS strains is different with emm genotyping and region.