新生儿B组链球菌感染传播途径的研究

目的 确定新生儿Ｂ组链球菌（ＧＢＳ）感染的传播途径和随机引物扩增多态性（ＲＡＰＤ）分型方法的应用价值。方法 采用血清学、核酸杂交和ＰＡＲＤ方法对２例诊断为早发型ＧＢＳ肺炎和晚发型ＧＢＳ脑膜炎患儿体内分离的５株ＧＢＳ和其母阴道分离的２株ＧＢＳ菌株作母婴配对分析,对８８株孕妇生殖道携带ＧＢＳ进行ＲＡＰＤ分型研究。结果 １例早发型ＧＢＳ肺炎母婴配对ＧＢＳ血清型均为ＩＩＬ／Ｒ型致病,毒力因子基因片段大小」

The different transmission of group B streptococcus infections in neonates

Objective To study the transmission of group B Streptococcus (GBS) in the neonatal infections and the value of randomly amplified polymorphic DNA(RAPD) analysis in the GBS epidemiology. Methods The serotyping, hybridization and RAPD typing methods were used. Seven strains of GBS were detected in 2 pairs of mother-baby, which included 2 strains from the 2 mothers and 5 strains from their babies with early and late-onset infections. Eighty-eight strains of GBS were detected in vaginas of pregnant womens. Results In the two cases, the strains from the paired mother and baby showed the identical serotype (III/R) and restriction fragment length of virulent factor genes that is , alpha and beta genes negative, ScaA 2kb, glnA 6.5kb and ScpB 2.6kb. In the case with early-onset infection, the strains from the paired mother and baby were revealed with the identical RAPD pattern ( RAPD1). In the case with late-onset infection, the strains from the paired mother and baby were revealed with different RAPD patterns, GBS strain isolated from mother was RAPD27, GBS strains from blood and CSF of the baby were RAPD1. Conclusion There may be a vertical transmission between mother and baby in early-onset of GBS infection and cross transmission in late-onset. RAPD analysis provides a valuable molecular tool for studying GBS epidemiology.