关键词: 肝炎病毒，乙型;妊娠并发症;病例对照研究;免疫组织化学;原位杂交

    摘 要:目的 探索乙型肝炎病毒(HBV)宫内传播的机制和时间. 方法 孕妇和新生儿血清HBsAg和HBV DNA检测采用ELISA和PCR法.引产胎儿肝组织和胎盘的HBsAg，HBxAg，HBcAg和HBV DNA检测采用ABC免疫组化染色和原位杂交. 结果 母亲外周血HBV高浓度(≥0.02μg·L-1 )、先兆早产和胎盘绒毛毛细血管内皮细胞HBV感染导致宫内感染发生的危险性比值比(OR)分别为7.06，13.08和16.15.胎盘HBV感染从孕早期、孕中期至足月分娩愈来愈严重且广泛.在足月分娩胎盘中，从母面蜕膜细胞至胎儿面绒毛毛细血管内皮细胞HBV感染率呈逐渐下降趋势，但胎儿宫内感染的OR值却越来越大.1例孕19wk引产胎儿肝组织中检出HBV DNA和抗原. 结论 胎儿宫内感染的发生可经2条途径，即血源性和细胞性.宫内感染可发生在孕19wk前，但主要时期是在孕晚期.

    Mechanism of intrauterine infection of hepatitis B virus

    YAN Yong-Ping，XU De-Zhong，WANG Fu-Sheng，MEN Ke，LIU Zhi-Hua

    Department of Epidemiology，Faculty of Preventive Medicine，Fourth Military Medical University，Xi'an710033，China

    Keywords:hepatitis B virus;pregnancy complications;case-control studies;immunohistochemistry;in situ hybridization

    Abstract:AIM To explore the mechanism and timing of hepatitis B virus(HBV)intrauterine infection.METHODS Serologic HBV infection markers of pregnant women and newborns were detected by ELISA and PCR.HBsAg，HBx-Ag，HBcAg and HBV DNA in placentas and fetal abortion liver tissue were determined by ABC immunohistochemical staining and in situ hybridization.RESULTS Intrauterine infection ORs of high concentration(≥0.02μg·L-1 )of HBV in maternal peripheral blood ......