乙型肝炎病毒宫内感染的传播途径及早期诊断

目的分析羊水、脐带血、母血、胎盘等组织中乙型肝炎病毒标志物(HBV M)及HBV DNA与胎儿感染的关系，探讨HBV母婴传播机制。方法采用微粒子化学发光及核酸扩增杂交梳技术对65例血液乙型肝炎表面抗原(HBsAg)阳性不同孕龄孕妇的羊水、母血、脐带血进行HBV M和HBV DNA检测，对自然流产胎儿或死亡婴儿的胎盘、肝脏、心脏、肺脏进行免疫组织化学检测。结果65例血液HBsAg阳性，不同孕龄孕妇的羊水中HBsAg阳性率为21．50％，脐带血阳性率为20．00％；母血、羊水．脐带血HBsAg、乙型肝炎e抗原(HBeAg)、抗-HBc、HBV DNA均阳性者为6．15％；HBsAg、抗-HBc、抗-HBc阳性、HBV DNA阴性者占13．85％。对4例血液、羊水、脐带血HBsAg、HBeAg、抗-HBc、HBV DNA阳性孕妇分娩或自然流产后胎盘、胎儿及死亡婴儿的肝脏、肺脏、心脏进行免疫组织化学检测发现，胎盘各层组织镜下均可见到HBsAg、HBcAg阳性细胞；在肝脏、肺脏组织中可见到HBsAg、乙型肝炎核心抗原(HBcAg)阳性细胞，心肌组织内未见有HBsAg、HBcAg阳性细胞。结论胎儿感染HBV与羊水、胎盘中的病毒相平行；HBV在宫内可感染胎儿血液、肝脏、肺脏等组织；羊水检测HBV M及HBV DNA可作为胎儿早期HBV感染的诊断依据之一。

An investigation on the transmission routes and early diagnosis of intrauterine infection induced by hepatitis B virus

Objective To analyze the relationship between the fetus infection and HBV M, HBV DNA in amniotic fluid, umbilical cord blood, maternal blood and placenta, and to explore the mechanism of vertical transmission of HBV. Methods Immunonetric assay and nucleic acid amplification hybri-comb were used. Both HBV M and HBV DNA were detected in amniotic fluid, vein blood, umbilical cord blood for each of 65 HBV-positive women in their different gestational periods, while immunohistochemical analysis was carried out on the tissue of placenta, liver, lung or heart from each abortive fetus/dead infant in the case. Results For all of the 65 HBsAg-positive women in their different gestational periods, the detected positive rate of HBsAg was 21.50% in amniotic fluid, and 20.00% in umbilical blood. The positive rate of HBsAg, HBeAg, Anti-HBc and HBV DNA detected in blood, amniotic fluid and umbilical blood was 6.15%. The cases with positive of HBsAg, Anti-HBe, Anti-HBc and negative HBV DNA were in a percentage of 13.85%. Immunohistochemical analysis on placentas after birth/abortion as well as the tissues of livers, lungs, hearts of the fetuses/dead infants in 4 cases of pregnant women with positive HBsAg, HBeAg, Anti-HBc or HBV DNA in blood, amniotic fluid or umbilical blood showed that HBsAg, HBeAg positive cells in the scope could be seen in every layer of the tissue of placenta, in the hepatic/pulmonary tissue, but not in the cardiac tissue. Conclusion The infection in amniotic fluid or placenta relates to HBV infection in fetus; intrauterine HBV may result in infection in organs such as blood, liver, or lung of a fetus; infection in the amniotic fluid may be another key route of the intrauterine infection of fetus, and the detection on HBV M or HBV DNA in amniotic may be used as one of diagnostic proofs of HBV infection of fetus in its early stage.