| OBJECTIVE: ①To study the risk factors of HBV intrauterine infection and HBV infection in placenta. ②To explore HBsAg-positive pregnant women'placentas HBV infection state and risk factors.③To explore the mechanism of HBV intrauterine transmission. METHODS: 360 pregnant women and 360 newborns were collected between July,2001 and November,2004 in Taiyuan infectious hospital.The epidemiological base line data involving gestation and postpartum were also collected. newborn'femoral vein blood within 24 hours after birth and maternal elbow vein blood were collected. At the same time,the placental tissues were also collected. Following studies were performed:HBsAg,HBeAg in gravidas'and newborns 'serum were tested by ELISA;HBVDNA in both serum were detected by Fluorescence Quantitative PCR (FQ-PCR);HBsAg in placentas were detected by immunohistochemistry ABC;Both HBsAg and IL-6 in infected placental tissues were detected by double labeling immunofluorescent histochemistry assay;risk factors of HBV intrauterine infection and placental HBV infection were analyzed by nested case-control study.Furthermore,the interaction among risk factors were also analyzed. All of the data was analyzed by the statistical packages Visual Fox Por 6.0,SPSS 10.0 for windows. RESULTS:1. HBV intrauterine infection rate was 16.87%(28/166)in sum and 31.25%(20/64)in both HBsAg and HBeAg positive mothers. 2. Nested case-control study analysis showed that risk factors of HBV intrauterine infection were HBVDNA positive in pregnant women (OR=6.96,1.42-34.12) and HBV infection in placentas (OR=2.65,1.01-6.96). There was no interaction between the two factors. The exposure rate of other factors did not reveal the difference in two groups. 3.The value of association between the HBV infection rate and different layers of placental cells and virus content in gravida 'serum both showed a gradient(trend test,χ~2,8.27,P﹤0.05 and χ~2 ,26.22,P﹤0.05). 4. The best critical predictive value of HBV intrauterine infection is HBVDNA≧156 copies/ml which were determined by Roc based on the HBVDNA quanto result in gravida 'serum,the sensitivity,specificity,positive and negative predictive value was 75.25%,74.33%,36.84% and 93.58% respectively. 5.126 of 360 placentas were infected by HBsAg.HBsAg was mostly located in the cytoplasm and occationally in the nuceus and on the cell membrane. HBV infection rate gradually decreased from the maternal side to the fetal side (trend test P<0.005) in the placental cell layers. Maternal decidual cells (35.00%)> trophoblastic cells (29.72%)> villous mesenchymal cells (22.78%)> villous capillary endothelial cells (10.28%). 6.Effect factors of placental HBV infection were antepartum injection HBIG over thrice (OR=0.21,0.09-0.52) and HBV DNA positive in maternal serum (OR=4.77, 2.06-11.05). The value of association between the HBV infection rate in different layers of placental cells and virus content in gravida 'serum showed a gradient(trend test, χ~2, 43.46;P<0.05). 7.HBsAg and IL-6 were found both positive in the same place of placental cells. CONCLUSION: 1. HBV intrauterine infection rate was 16.87% for HBsAg and/or HBV DNA positive in neonatal serum. 2. The risk factors of HBV intrauterine infection were HBV infection in placental tissues and HBVDNA positive in pregnant women. 3.the risk of HBV intrauterine transmission was higher when HBV infection occurred in placental cells that were closer to the fetus,which also will be raised complying with the HBVDNA increasing in pregnant women. It is very important to comprehend the HBVDNA level in pregnant women to diagnose HBV intrauterine infection.4.HBV can infect different layers of placental cells. Main approach of HBV invasiving newborns via placenta was mediated by "cell transfer". Placental barrier can offer conservancy effect on fetus to some extent. 5.The risk factor of HBV infection in placenta was HBV DNA positive in maternal serum, which also will be higher if virus content in gravida'serum increase.Antepartum injection HBIG over thrice can effectively...
|
PDF Full Text Request