Relationship of hepatitis B virus infection of placental barrier and hepatitis B virus intra-uterine transmission mechanism

Association of gestational hepatitis B virus infection and antiviral therapy with pregnancy outcomes: A retrospective study

OBJECTIVE

To explore the relationships between gestational hepatitis B virus (HBV) infection, antiviral therapy, and pregnancy outcomes.

METHODS

We retrospectively selected hepatitis B surface antigen (HBsAg)-positive pregnant women hospitalized for delivery at Fujian Medical University Affiliated Hospital from October 1, 2016 to October 1, 2020. The control group included randomly selected healthy pregnant women hospitalized for delivery during the same time.

RESULTS

Overall, 1115 participants were enrolled and grouped into control (n = 380) and HBsAg-positive groups (n = 735), which were further divided into groups I (n = 407; low viral load), II (n = 207; high viral load without antiviral therapy), and III (n = 121; high viral load with antiviral therapy). Pregnant women with HBV were positively correlated with the incidence of intrahepatic cholestasis of pregnancy (ICP) (adjusted odds ratio [aOR] 5.1, 95% confidence interval [CI] 2.62-9.92, P < 0.001), neonatal jaundice (aOR 10.56, 95% CI 4.49-24.83, P < 0.001), and neonatal asphyxia (aOR 5.03, 95% CI 1.46-17.27, P = 0.01). Aspartate aminotransferase (AST) greater than the upper limit of normal (ULN) was an independent risk factor for increased ICP incidence (aOR 3.49, 95% CI 1.26-9.67, P = 0.019). Antiviral therapy considerably reduced HBV DNA and improved liver function. High viral load and antiviral therapy did not correlate significantly with adverse pregnancy outcomes (P < 0.05).

CONCLUSION

Pregnant women with HBV have significantly elevated incidence of ICP, neonatal jaundice, and neonatal asphyxia not significantly correlated with viral load. AST greater than ULN independently increases the risk of ICP. Antiviral therapy effectively reduces viral replication and improves liver function without increasing the risk of adverse outcomes.

The effect of intrahepatic cholestasis in pregnancy combined with different stages of hepatitis B virus infection on pregnancy outcomes: a retrospective study

BACKGROUND AND AIMS

To investigate the impact of intrahepatic cholestasis of pregnancy (ICP) with hepatitis B virus (HBV) infection on pregnancy outcomes.

METHODS

We selected 512 pregnant women, collected the data including maternal demographics, main adverse pregnancy outcomes and maternal HBV infected markers HBeAg and HBV-DNA loads status, then have a comparative analysis.

RESULTS

There were 319 solitary ICP patients without HBV infection (Group I) and 193 ICP patients with HBV infection. Of the latter, there were 118 cases with abnormal liver function(Group II) and 80 cases with normal liver function(Group III). All HBV-infected pregnant women with ICP were divided into hepatitis Be antigen (HBeAg)-positive group (102 cases) and HBeAg-negative group (91 cases), according to the level of the serum HBeAg status; and into high viral load group (92 cases), moderate viral load group (46 cases) and low viral load group (55 cases) according to the maternal HBV-DNA level. Group II had a higher level of serum total bile acids, transaminase, bilirubin as well as a higher percentage of premature delivery, neonatal intensive care unit (NICU) admission and meconium-stained amniotic fluid (MSAF) compared with the other two groups(P < 0.05), but there were no significant differences in the above indicators between the Group I and Group III. Among the HBV-infected patients with ICP, HBeAg-positive group had a higher level of serum transaminase, bilirubin and bile acid as well as earlier gestational weeks of delivery, lower birth weight of new-borns and a higher rate of NICU admission than HBeAg-negative group (P < 0.05). Those with a high viral load (HBV-DNA > 106 IU/ml) had a higher level of transaminase, bilirubin, and bile acid as well as shorter gestational weeks of delivery, lower birth weight of new-borns and a higher rate of NICU admission compared with those with a low or moderate viral load (P < 0.05).

CONCLUSION

HBV-infected pregnant women with ICP combined with abnormal liver function have more severe liver damage, a higher percentage of preterm birth and NICU admission. HBeAg-positive status and a high HBV-DNA load will increase the severity of conditions in HBV-infected pregnant women with ICP. HBV-infected patients with ICP who have abnormal liver function, HBeAg-positive or a high viral load should be treated more actively.

Antenatal hepatitis B virus sero-prevalence, risk factors, pregnancy outcomes and vertical transmission rate within 24 months after birth in a high HIV prevalence setting

BACKGROUND

Despite the availability of an effective vaccine, chronic hepatitis B virus (HBV) infections remain a major cause of liver cirrhosis and hepatocellular carcinoma. HBV burden in pregnancy, risk factors and the timing of mother to child transmission remain poorly described especially during this era of lifelong use of Tenofovir/Lamivudine/Efavirenz as firstline for HIV treatment. We aimed to determine the burden of HBV in pregnancy and infants receiving their first dose of HBV vaccine 6 weeks after birth in a high HIV-prevalence setting.

METHODS

Pregnant women ≥ 20 weeks' gestational age were enrolled and followed up as mother-infant dyads from delivery, 6, 24 and 96 weeks after birth. HBV surface antigen (HBsAg) was tested (fresh plasma, immunochromatography) in pregnancy. Women testing HBsAg-seropositive were further evaluated for other four HBV-biomarkers. Maternally HBV exposed babies were tested for HBsAg from birth and HBs-antibodies from 6 months of age. Maternal-infant factors were tested in univariable and multivariable analyses for predictors of HBsAg-seropositivity.

RESULTS

Six hundred HIV-uninfected and 608 HIV-infected women on Tenofovir/Lamivudine/Efavirenz-regimen with median (interquartile range) 350: (87-1477) days of therapy use were enrolled. The overall HBsAg-seroprevalence was 32/1208: 2.65%, 95% confidence interval (CI) [1.74, 3.55]; being 7/600: 1.17%, 95% CI [0.37, 1.97] and 25/608: 4.11%, 95% CI [2.52, 5.68] in HBsAg-monoinfected and HBsAg/HIV-coinfected respectively, disproportionately detected in 31/32: 96.9%, 95% CI [90.8, 100] women presumably HBV-unvaccinated in infancy. HBV exposed babies tended to be born prematurely (< 37 weeks); 15.2% versus 9.9% in the HBV-unexposed, p = 0.009. In multivariate logistic regression-models with variable elimination, HIV-infection and reported tooth extractions predicted antenatal HBsAg-seropositivity; odds ratios (CI): 3.85 (1.61-10.7) and 2.46 (1.07-5.34), respectively. None of the exposed infants were HBsAg-seropositive neither before nor after 6 weeks of age. No HBs-antibodies were detected in 23.3% of HBsAg-exposed infants at two years despite having successfully completed the HBV vaccination schedule.

CONCLUSION

Low and moderate HBV endemics were observed in HIV-uninfected and HIV-infected pregnant women, respectively. This underscores the need to routinely screen for HBV in pregnancy, especially the HIV-infected attending antenatal-care. Being HIV-infected and reported tooth extractions were independent risk factors for maternal HBsAg-seropositivity. Vertical and child horizontal transmissions were both absent, probably due to ~ the 50% frequency of antenatal anti-HBe-antibodies observed. Of concern was the absence of anti-HBs-antibodies in 23.3% of fully vaccinated/maternally HBV-exposed infants by two years. Absence of molecular diagnosis may have underestimated HBV burden.

TRIAL REGISTRATION

www.

CLINICALTRIALS

gov , trial registration number: NCT04087239.

Altered expression of endosomal Toll-like receptors and HBeAg seropositivity may act synergistically towards the vertical transmission of HBV

PROBLEM

Hepatitis B is one of the leading causes of mortality in India. Despite the mass vaccination programme, the burden of the infection is still increasing due to its vertical transmission. Asymptomatic nature of hepatitis B virus (HBV) infection owing to immune tolerance among pregnant women is a major issue in this regard.

METHOD OF STUDY

As such, this study aims to investigate the potential role of altered Toll-like receptor (TLR) expression (TLR-3, 7 and 9) along with peripheral blood HBeAg status in attaining differential cord blood (CB) HBV DNA status.

RESULT

Expression analysis reveals an overall downregulation of expression with mean ± SD value 1.14 ± 1.05, 0.86 ± 0.5 and 0.71 ± 0.4 (TLR 3, 7 and 9, respectively) upon comparison with healthy women. Further stratification based on CB HBV DNA status; the downregulation of expression was found to be significantly (p < .05) associated with positive CB HBV DNA status apart from peripheral HBeAg status. One hundred percent HBeAg positive parturiting women exhibit positive CB HBV DNA. Pearson's correlation analysis reveals a positive correlation between CB HBV DNA status and altered TLR expression, HBeAg status and mother HBV DNA status and as such can be associated with the potential risk of HBV vertical transmission.

CONCLUSION

This study suggests that the downregulation of TLR 3, 7 and 9 may be a risk factor for potential vertical transmission of HBV.

Vertical transmission of hepatitis B virus from father to child: what can be concluded about this possibility?

Vertical hepatitis B virus (HBV) transmission is defined as transmission that occurs during pregnancy or postpartum from an HBV-infected mother to her fetus or child. It is an efficient route for the spread of HBV and is responsible for most of the cases of chronic HBV infection in adults. During pregnancy, vertical transmission can occur in the intrauterine phase, by placental infection via peripheral blood mononuclear cells, by placental leakage, or through female germ cells.The detection of HBV DNA in semen and spermatids from HBV-infected men has provided strong evidence that the male genital tract may act as a reservoir of the virus in HBV-infected men, supporting the possibility that vertical HBV transmission from an HBV-infected father to his child may also occur via the germ line at the time of fertilization, as occurs in HBV transmission from mother to child. Furthermore, it has been shown that integration of the HBV genome into the sperm cell genome can compromise sperm morphology and function and even cause hereditary or congenital biological effects in the offspring when an HBV-infected sperm fuses with an ovum.Since vertical HBV transmission from father to child can be a topic of interest and of global importance for controlling the spread of HBV, this article addresses the evidence supporting its occurrence via germ cells, the biological impact of integration of the HBV genome into the male germ cell genome, and the role of maternal immunoprophylaxis in vertical HBV transmission from father to child.

Maternal Preconception Hepatitis B Virus Infection and Risk of Congenital Heart Diseases in Offspring Among Chinese Women Aged 20 to 49 Years

Importance

Maternal hepatitis B virus (HBV) infection during early pregnancy has been related to congenital heart diseases (CHDs) in offspring. However, no study to date has evaluated the association of maternal preconception HBV infection with CHDs in offspring.

Objective

To explore the association of maternal preconception HBV infection with CHDs in offspring.

Design, Setting, and Participants

This retrospective cohort study used nearest-neighbor (1:4) propensity score matching of 2013 to 2019 data from the National Free Preconception Checkup Project (NFPCP), a national free health service for childbearing-aged women who plan to conceive throughout mainland China. Women aged 20 to 49 years who got pregnant within 1 year after preconception examination were included, and those with multiple births were excluded. Data were analyzed from September to December 2022.

Exposures

Maternal preconception HBV infection statuses, including uninfected, previous, and new infection.

Main Outcomes and Measures

The main outcome was CHDs, which were prospectively collected from the birth defect registration card of the NFPCP. Logistic regression with robust error variances was used to estimate the association between maternal preconception HBV infection status and CHD risk in offspring, after adjusting for confounding variables.

Results

After matching with a 1:4 ratio, there were 3 690 427 participants included in the final analysis, where 738 945 women were infected with HBV, including 393 332 women with previous infection and 345 613 women with new infection. Approximately 0.03% (800 of 2 951 482) of women uninfected with HBV preconception and women newly infected with HBV carried an infant with CHDs, whereas 0.04% (141 of 393 332) of women with HBV infection prior to pregnancy carried an infant with CHDs. After multivariable adjustment, women with HBV infection prior to pregnancy had a higher risk of CHDs in offspring compared with women who were uninfected (adjusted relative risk ratio [aRR], 1.23; 95% CI, 1.02-1.49). Moreover, compared with couples who were uninfected with HBV prior to pregnancy (680 of 2 610 968 [0.026%]), previously infected women with uninfected men (93 of 252 919 [0.037%]) or previously infected men with uninfected women (43 of 95 735 [0.045%]) had a higher incidence of CHDs in offspring and were significantly associated with a higher risk of CHDs in offspring (previously infected women with uninfected men: aRR, 1.36; 95% CI, 1.09-1.69; previously infected men with uninfected women: aRR, 1.51; 95% CI, 1.09-2.09) with multivariable adjustment, while no significant association was observed between maternal new HBV infection and CHDs in offspring.

Conclusions and Relevance

In this matched retrospective cohort study, maternal preconception previous HBV infection was significantly associated with CHDs in offspring. Moreover, among women with HBV-uninfected husbands, significantly increased risk of CHDs was also observed in previously infected women prior to pregnancy. Consequently, HBV screening and getting HBV vaccination-induced immunity for couples prior to pregnancy are indispensable, and those with previous HBV infection prior to pregnancy should also be taken seriously to decrease the CHDs risk in offspring.

Impact of maternal hepatitis B carrier status on congenital abnormalities: a systematic review and meta-analysis

OBJECTIVES

This study aims to explore whether maternal hepatitis B carrier status is associated with an increased risk of congenital abnormalities.

DESIGN

A systematic review and meta-analysis of observational studies.

DATA SOURCES

PubMed, Embase (Ovid), Scopus, the China National Knowledge Infrastructure (CNKI) and the Wanfang databases.

STUDY SELECTION

Five databases were searched systematically from inception to 7 September 2021. Cohort and case-control studies that investigated the association between maternal hepatitis B virus (HBV) infection and congenital abnormalities were included. This study was conducted according to MOOSE (Meta-analysis of Observational Studies in Epidemiology) guidelines.

DATA EXTRACTION AND SYNTHESIS

Two reviewers independently collected data, as well as assessed risk of bias by using Newcastle-Ottawa Scale. We pooled crude relative risk (cRR) and adjusted OR (aOR) by DerSimonian-Laird random-effects model. Heterogeneity was explored by I ² statistics, Cochran's Q test. Several subgroup analyses and sensitivity analyses were performed.

RESULTS

In total, 14 studies involving 16 205 pregnant women exposed to HBV were included. The pooled cRR of 1.15 (95% CI: 0.92 to 1.45; 14 studies included) showed a marginal but not significant association between maternal HBV-carrier status and congenital abnormalities. However, the pooled aOR of 1.40 (95% CI: 1.01 to 1.93; 8 studies included) indicated that pregnant women with HBV infection might be associated with a higher risk of congenital abnormalities. Subgroup analyses of adjusted data showed a higher pooling cRR or aOR on high prevalence HBV infection populations, as well as studies from Asia and Oceania.

CONCLUSIONS

Maternal hepatitis B carrier status might be at potential risk for congenital abnormalities. The existing evidence was not sufficient to draw a firm conclusion. Additional studies may be warranted to confirm the association.

PROSPERO REGISTRATION NUMBER

CRD42020205459.

Effects of hepatitis B virus infection and strategies for preventing mother-to-child transmission on maternal and fetal T-cell immunity

One of the most common routes of chronic hepatitis B virus (HBV) infection is mother-to-child transmission (MTCT). Approximately 6.4 million children under the age of five have chronic HBV infections worldwide. HBV DNA high level, HBeAg positivity, placental barrier failure, and immaturity of the fetal immune are the possible causes of chronic HBV infection. The passive-active immune program for children, which consists of the hepatitis B vaccine and hepatitis B immunoglobulin, and antiviral therapy for pregnant women who have a high HBV DNA load (greater than 2 × 10⁵ IU/ml), are currently two of the most important ways to prevent the transmission of HBV from mother to child. Unfortunately, some infants still have chronic HBV infections. Some studies have also found that some supplementation during pregnancy can increase cytokine levels and then affect the level of HBsAb in infants. For example, IL-4 can mediate the beneficial effect on infants' HBsAb levels when maternal folic acid supplementation. In addition, new research has indicated that HBV infection in the mother may also be linked to unfavorable outcomes such as gestational diabetes mellitus, intrahepatic cholestasis of pregnancy, and premature rupture of membranes. The changes in the immune environment during pregnancy and the hepatotropic nature of HBV may be the main reasons for the adverse maternal outcomes. It is interesting to note that after delivery, the women who had a chronic HBV infection may spontaneously achieve HBeAg seroconversion and HBsAg seroclearance. The maternal and fetal T-cell immunity in HBV infection is important because adaptive immune responses, especially virus-specific CD8 T-cell responses, are largely responsible for viral clearance and disease pathogenesis during HBV infection. Meanwhile, HBV humoral and T-cell responses are important for the durability of protection after fetal vaccination. This article reviews the literature on immunological characteristics of chronic HBV-infected patients during pregnancy and postpartum, blocking mother-to-child transmissions and related immune mechanisms, hoping to provide new insights for the prevention of HBV MTCT and antiviral intervention during pregnancy and postpartum.

Association of Toll-Like Receptor 2 (TLR2) Expression in Placenta and Intrauterine Exposure to Hepatitis B Virus

Introduction

The placenta is a specialized organ that only performs during pregnancy and serves as an immunological barrier in preventing pathogens to reach the fetus. It has been known that toll-like receptors (TLRs) on the placenta respond to antigens, such as zymosan, lipopolysaccharide, and other viral infections. This study analyzes the distribution of TLR2 protein and hepatitis B DNA virus (HBV DNA) virus identification to gain an understanding of hepatitis B viral transmission from the mother to child.

Methods

We performed enzyme-linked immunoadsorbent assay of HBeAg, HBsAg titer, Anti-HBs, and Anti-HBc to 59 HBsAg-positive pregnant women and identified HBV DNA using nested PCR in their cord blood during delivery for evidence of exposure to HBV DNA. The expression of TLR2 protein in the placenta was performed using immunohistochemistry analysis.

Results

Intrauterine exposure to the hepatitis B virus occurred in 69.5% of all pregnant women who were HbsAg positive. TLR2 expression was predominantly identified in syncytiotrophoblast and cytotrophoblast cells with the highest score in mothers aged 20–35 years (75%), multigravida (58.3%), and mothers with term pregnancies (70.8%). Statistical analysis results showed that placental TLR2 expression did not indicate any association with hepatitis B virus DNA identified in cord blood with a p value of 0.730 and an OR of 0.650 (95% CI 0.173–2.440).

Conclusion

TLR2 expression is not associated with intrauterine exposure of hepatitis B virus.

The S100A10-AnxA2 complex is associated with the exocytosis of hepatitis B virus in intrauterine infection

Mother-to-child transmission (MTCT) is the major cause of chronic infection of hepatitis B virus (HBV) in patients. However, whether and how HBV crosses the placenta to cause infection in utero remains unclear. In this study, we investigate the mechanism as to how the HBV virions pass through layers of the trophoblast. Our data demonstrate the exocytosis of virions from the trophoblast after exposure to HBV where the endocytosed HBV virions co-localized with an S100A10/AnxA2 complex and LC3, an autophagosome membrane marker. Knockdown of either AnxA2 or S100A10 in trophoblast cells led to a reduction of the amount of exo-virus in Transwell assay. Immunohistochemistry also showed a high expression of AnxA2 and S100A10 in the placental tissue samples of HBV-infected mothers with congenital HBV-positive infants (HBV+/+). We conclude that in HBV intrauterine infection and mother-to-child transmission, a proportion of HBV hijacks autophagic protein secretion pathway and translocate across the trophoblast via S100A10/AnxA2 complex and multivesicular body (MVB)-mediated exocytosis. Our study provides a potential target for the interference of the mechanisms of HBV intrauterine infection and mother-to-child transmission.

Viral Infections During Pregnancy: The Big Challenge Threatening Maternal and Fetal Health

Viral infections during pregnancy are associated with adverse pregnancy outcomes, including maternal and fetal mortality, pregnancy loss, premature labor, and congenital anomalies. Mammalian gestation encounters an immunological paradox wherein the placenta balances the tolerance of an allogeneic fetus with protection against pathogens. Viruses cannot easily transmit from mother to fetus due to physical and immunological barriers at the maternal-fetal interface posing a restricted threat to the fetus and newborns. Despite this, the unknown strategies utilized by certain viruses could weaken the placental barrier to trigger severe maternal and fetal health issues especially through vertical transmission, which was not fully understood until now. In this review, we summarize diverse aspects of the major viral infections relevant to pregnancy, including the characteristics of pathogenesis, related maternal-fetal complications, and the underlying molecular and cellular mechanisms of vertical transmission. We highlight the fundamental signatures of complex placental defense mechanisms, which will prepare us to fight the next emerging and re-emerging infectious disease in the pregnancy population.

Hepatitis B Virus Infection in Pregnancy: Immunological Response, Natural Course and Pregnancy Outcomes

This review aimed to provide an update on the impact of pregnancy on the natural course of hepatitis B virus (HBV) infection and also on the impact of HBV infection on adverse pregnancy outcomes, including mother-to-child transmission (MTCT). For the literature review, original research articles, review articles, and guidelines were narratively reviewed and comprehensively validated. The databases of PubMed, EMBASE, and CINAHL were carefully searched for articles in English on topics related to HBV infection, pregnancy, and vertical transmission from 1960 to May 2021. Immunological changes during pregnancy such as suppression of Th1 response and induction of Th2 immunity lead to an impaired immune reaction to HBV and stimulate viral activity along with the reduction of CD8 T cells to escape immune detection. The impact of pregnancy on the natural course of chronic HBV infection seems to be minimal, while pregnancy can increase morbidity and mortality in the case of advanced HBV hepatitis or cirrhosis. Importantly, hepatitis flare or alanine aminotransferase (ALT) flare can occur during pregnancy and is more common during the postpartum period due to the interaction between HBV and the immune response. Interestingly, the impact of HBV infection on adverse pregnancy outcomes is more serious than ever thought. Updated evidence indicates that pregnancies with chronic HBV infection increase the risk of preterm birth and gestational diabetes, especially in cases of positive hepatitis e antigen (HBeAg).

Placental Immune Responses to Viruses: Molecular and Histo-Pathologic Perspectives

As most recently demonstrated by the SARS-CoV-2 pandemic, congenital and perinatal infections are of significant concern to the pregnant population as compared to the general population. These outcomes can range from no apparent impact all the way to spontaneous abortion or fetal infection with long term developmental consequences. While some pathogens have developed mechanisms to cross the placenta and directly infect the fetus, other pathogens lead to an upregulation in maternal or placental inflammation that can indirectly cause harm. The placenta is a temporary, yet critical organ that serves multiple important functions during gestation including facilitation of fetal nutrition, oxygenation, and prevention of fetal infection in utero. Here, we review trophoblast cell immunology and the molecular mechanisms utilized to protect the fetus from infection. Lastly, we discuss consequences in the placenta when these protections fail and the histopathologic result following infection.

Translational Strategies to Eliminate Chronic Hepatitis B in Children: Prophylaxis and Management in East Asian Countries

Translational medical research on hepatitis B virus (HBV) infection and chronic hepatitis B (CHB) pathogenesis provides guidance on strengthening the treatment and prevention strategies of CHB. Preventing vertical transmission is the key to eliminating HBV infection in children. The understanding of HBV replication, hepatocyte turnover, and the fate of covalently closed circular DNA (cccDNA) would help establish a personalized application of the guidelines, especially concerning the discontinuation of nucleos(t)ide analog (NA) treatment in children. Transplacental leakage of HBV-infected maternal blood is suggested as the leading cause of vertical transmission. Prenatal maternal prophylaxis could diminish maternal HBV viremia at delivery, to reduce the risk of neonatal HBV infection. The meaning of the expression "no additional risk of breast milk feeding" is thereby explained. Understanding the untreated natural course of CHB in children and the course changeable by treatment is important to apply individualistic strategies and avoid the immoral selection of treatment indications. NAs with potent efficacy and a high barrier to drug resistance should be used as first-line treatment to reduce the likelihood of NA-resistant HBV development because the rate of mutant HBV emergence might count on the infected hepatocyte turnover rate in chronic HBV infection. Although elimination of intranuclear cccDNA is difficult by NAs alone, a cure is possible by human immunity and hepatocyte turnover. The reduction of intranuclear cccDNA occurs after the destruction of HBV-infected hepatocytes, non-cytolytic immune response, apoptosis of hepatocytes, and compensatory cell proliferation. Therefore, consolidation therapy after NA-induced hepatitis B e-antigen seroconversion must be necessary for a sufficient period. This review also summarizes the treatment strategies of CHB in children based on the practical application of translational research.

Quantitative HBsAg and Qualitative HBeAg Predicts Intrauterine Placental Infection and Umbilical Blood Cord in Pregnant Women

Objective: To know the correlation between quantitative Hepatitis B surface Antigen (HbsAg) and maternal Hepatitis B Envelope Antigen (HbeAg) with hepatitis B intrauterine transmission via placental infection. Hepatitis B in pregnancy causes a mother to child transmission (MTCT) via transplacental route started with placental infection. HBV DNA viral load and HBeAg are the independent risk factors for MTCT, but it rarely available in developing country.

Materials and methods: A cross-sectional study in 33 pregnant women with HbsAg positive in 4 referral hospital in East Java, Indonesia. Quantitative HBS Ag and HBeAg) status were determined serologically from a peripheral venous blood sample. Placental Hepatitis B infection was detected by immunohistochemistry of HBsAg from placental tissues. The intrauterine transmission was diagnosed by positive HBsAg in cord blood sampling after deliveries.

Results: Serum quantitative HBsAg level has a good sensitivity and spesificity to predict placental infection (90% and 83%), with a cut off value of 3.14 Log10 IU/mL (AUC 0.87; 95% CI: 0.74-0.99). Quantitative HBsAg level also has a good sensitivity and spesificity to predict HBV transmission in umbilical blood cord (81.8% and 95.5%) with a cut off value of 3.62 log₁₀ IU/ml (AUC: 0.925, 95% CI: 0.813-1; p = 0.000). Placental infection is significantly related with intrauterine transmission with OR 4.6 (95% CI 2.29-9.4; p = 0.002).

Conclusion: The study reveals that maternal serum quantitative HBsAg level can be used as an alternative test to substitute HBeAg or HBV DNA as a marker to predict the placental infection and intrauterine transmission, especially in low-middle income countries.

Cesarean section in reducing mother-to-child HBV transmission: a meta-analysis

BACKGROUND

A meta-analysis (MA) of natural vs. cesarean births in HBV infected mothers was performed to assess which delivery methods could minimize the mother-to-child transmission (MTCT) of Hepatitis B virus (HBV).

METHODS

Electrical databases PubMed, Embase and Cochrane Library were searched for the English papers about the HBV MTCT up to 19 August 2019. STATA 11.0 software was used for all analysis. Odds ratio (OR) and 95% confidence interval (CI) were used to present the effect size for MTCT at birth and MTCT more than 6 months. Heterogeneity was evaluated using the chi-squared Q and I ² test to determine the use of random effects model or fixed effects model.

RESULTS

A total of 19 articles involving 11,144 HBV-positive pregnant women (5251 underwent natural delivery and 5893 received a cesarean section) were included in the study. The pooled OR for MTCT at birth was 0.42, 95% CI: 0.23-0.76 based on random effect model (I ² = 69.9%, p = .019). Meanwhile, in fixed effect model (I ² = 0.0%, p = .470), the pooled OR for MTCT more than 6 months was 0.62, 95% CI: 0.48-0.81. The results indicated that HBV infection in cesarean births significantly lower than that of vaginal delivery. Subgroup analysis of MTCT more than 6 months was clearly, and the results indicated that cesarean section significantly reduced the risk of MTCT (OR = 0.62, 95% CI: 0.48-0.81, p < .001).

CONCLUSIONS

Cesarean section can reduce the risk of HBV MTCT and should be employed as a preventive measure. Due to the limitations of this study, further multi-center, large-sample randomized controlled trials must be performed to confirm these findings.

Maternal hepatitis B infection status and adverse pregnancy outcomes: a retrospective cohort analysis

PURPOSE

To investigate the association between maternal HBsAg-positive status and pregnancy outcomes.

METHODS

The study enrolled women with singleton pregnancies who delivered during January-December 2018. Data of maternal demographics and main adverse pregnancy outcomes were collected from the institutional medical records and analyzed by univariate and multivariate logistic regression models to determine the association between maternal HBV markers (HBsAg/HBeAg/HBV-DNA loads status) and adverse pregnancy outcomes.

RESULTS

Total 1146 HBsAg-positive and 18,354 HBsAg-negative pregnant women were included. After adjusting for potential confounding variables, maternal HBsAg-positive status was associated with a high risk of gestational diabetes mellitus (GDM) [adjusted odds ratio (aOR) = 1.24; 95% confidence interval (CI) 1.07-1.43], intrahepatic cholestasis of pregnancy (ICP) (aOR = 3.83; 95% CI 3.14-4.68), preterm birth (aOR = 1.42; 95% CI 1.17-1.72), and neonatal asphyxia (aOR = 2.20; 95% CI 1.34-3.63). Further, higher risks of ICP and neonatal asphyxia remained with either HBeAg-positive status (aOR = 1.64; 95% CI 1.10-2.44; aOR = 3.08; 95% CI 1.17-8.00) or high HBV-DNA load during the second trimester (aOR = 1.52; 95% CI 1.06-2.35; aOR = 4.20; 95% CI 4.20-15.83) among HBsAg-positive pregnant women.

CONCLUSION

Women with maternal HBsAg-positive status may have increased risks of GDM, ICP, preterm birth, and neonatal asphyxia; furthermore, the risks of ICP and neonatal asphyxia were higher in women with HBeAg-positive status and a high HBV-DNA load during the second trimester among the HBsAg-positive pregnant women, implying that careful surveillance for chronic HBV infection during pregnancy is warranted.

Prevalence and characteristics of hepatitis C virus infection in Shenyang City, Northeast China, and prediction of HCV RNA positivity according to serum anti-HCV level: retrospective review of hospital data

Objective

The prevalence of hepatitis C virus (HCV) infection is typically evaluated based on the current rate of positivity of anti-HCV antibody; however, HCV RNA positivity is considered the main criterion for antiviral treatment of HCV infection in the clinical setting. In this study, we evaluated the prevalence of HCV infection based on anti-HCV and HCV RNA detection in the population of Liaoning Province, and investigated the correlation between serum HCV RNA positivity and anti-HCV levels.

Methods

A total of 192,202 patients who underwent serum anti-HCV examination at Shengjing Hospital in 2018 were enrolled in the study. Anti-HCV production was tested using a chemiluminescence assay, and serum HCV RNA detection was performed with Roche COBAS TaqMan (CTM) Analyzer.

Results

The prevalence of anti-HCV was 1.21 and 0.93% among male and female patients in Liaoning Province, respectively. The positive rates of anti-HCV and serum anti-HCV levels were both age-related, in which patients over 40 years of age had a significantly higher anti-HCV positive rate than those younger than 40 years. Among the anti-HCV-positive patients, the average HCV RNA positive rate was 51.66 and 35.93% in males and females, respectively. Spearman rank analysis showed a significantly positive correlation between serum HCV RNA positivity and the level of anti-HCV. The best cut-off value using serum anti-HCV levels to predict the positivity of HCV RNA was determined to be 9.19 signal-to-cut-off ratio (s/co) in males and 10.18 s/co in females.

Conclusion

The prevalence of anti-HCV in the general population of Liaoning Province was around 1.04%, which was higher than that previously reported from a national survey of HCV infection in China. Approximately 42.9% of the anti-HCV-positive patients also tested positive for HCV RNA. However, the positive correlation between the serum anti-HCV and HCV RNA levels suggests that the positivity of serum HCV RNA can be predicted according to the anti-HCV level in anti-HCV-positive patients, which can improve screening and facilitate timely intervention to prevent the spread of infection.

Hepatitis B - Vertical transmission and the prevention of mother-to-child transmission

Hepatitis B virus (HBV) infection is the commonest cause of chronic hepatitis, with an estimated global prevalence of 3.5%, and which leads to significant morbidity and mortality. Mother-to-child transmission (MTCT) during pregnancy is the leading form of transmission in endemic populations, and its interruption is thus crucial as the initial step in the elimination of HBV infection, notwithstanding the availability of potent antiviral medications. The risk of MTCT is dramatically reduced by timely neonatal HBV vaccination and the administration of hepatitis B immunoglobulin after birth in high-risk infants. Maternal HBV DNA quantification during pregnancy allows the assessment of the risk of newborn immunoprophylaxis failure (IF). Maternal antiviral treatment in highly viremic women can reduce the risk of IF. However, the optimal HBV DNA cutoff level for the initiation of antiviral treatment remains to be determined.

Maternal age and educational level modify the association between chronic hepatitis B infection and preterm labor

BACKGROUND

Few studies have investigated whether maternal age and education level modify the association of chronic hepatitis B virus (HBV) infection with preterm labor. We hypothesized that the association of HBV infection with preterm labor is modified by maternal age and education level.

METHODS

A retrospective cohort study was conducted on the HBsAg-positive and HBsAg-negative pregnant women delivered from June 2012 to August 2017 at Wuhan Medical Care Center for Women and Children, Wuhan, China. A multivariate regression model was used in this study.

RESULTS

This study included 2050 HBsAg-positive pregnant women and 2050 HBsAg negative women. In the stratified analyses, positive HBsAg status was associated with the increased risk of preterm labor in women aged < 30 years, having low educational level, with an odds ratio of 1.65(95% CI 1.07-2.54) and 2.59(95% CI 1.41-4.76), respectively. Breslow-Day test showed that there existed significant differences in the ORs for HBsAg carriage across each stratum of maternal age (p = 0.023), educational level (p = 0.002). After adjusting other co-variables, we observed maternal HBV infection (OR 1.60, 95% CI 1.03-2.49) was still associated with risk of preterm labor in pregnancy women with age < 30. Similarly, the significant association of HBV infection (OR 2.49, 95% CI 1.34-4.63) with preterm labor remained in low educated women.

CONCLUSIONS

Our results indicated that HBV infection was associated with high risk of preterm labor, but maternal age and educational level could modify the association between HBV infection and preterm labor.

The Prevalence of HBV Infection: A Retrospective Study of 13 Years in a Public Hospital of Northeast China

The prevalence of hepatitis B virus (HBV) infection was an imbalance in different provinces of China. This study aimed to investigate the prevalence of HBV infection and evaluate the prophylactic measures in a public hospital of northeast China over the preceding 13 years. A total of 13,948 patients in 2004 and 15,256 patients in 2017 of Shengjing Hospital of China Medical University were tested of serum HBsAg, HBeAg, HBsAb, HBeAb, and HBcAb levels with Abbott MEIA Kits. In people born before 1992, HBsAg-positive rate was 5.45% and 6.47%; isolated HBsAb positive rate was 14.62% and 21.24%; HBV marker negative rate was 54.27% and 42.77% in 2004 and 2017 survey, respectively. The males had a significant higher HBsAg-positive rate than the females. In people born during 1992-2004, HBsAg positive rate was 0.58% and 0.57%, isolated HBsAb positive rate was 41.47% and 46.57%; and HBV marker negative rate was 51.97% and 46.86% in 2004 and 2017 survey, respectively. Males and females had no difference of HBsAg-positive rate. In children born after 2005, HBsAg positive rate was 0.11%, isolated HBsAb positive rate was 76.68%, and HBV marker negative rate was 18.51% in 2017 survey. No difference of HBsAg-positive rate was found between the genders. A dramatic decrease of HBsAg positive rate and a progressive increase of HBsAb-positive rate were found among people born after 1992 and progressed further in those born after 2005. Immunization of infants and timely birth dose was the key method for prevention of HBV infection. Expanded HB vaccination would be needed for people born before 2005, especially those born between 1992 and 2004.

Maternal hepatitis B or C status and the long-term risk of gastrointestinal morbidity for offspring: A population-based cohort study

BACKGROUND

More than 360 million people have chronic hepatitis B or C (HBV/HCV) infection worldwide, many of which are women at childbearing age. While the risk of perinatal HBV/HCV has been well established, the long-term implications on offspring health, have been less studied. We aimed to evaluate the association between maternal HBV/HCV carrier status and long-term gastrointestinal (GI) morbidities in offspring.

AIMS & METHODS

A population-based cohort analysis compared the risk for long-term childhood GI morbidities in children born to HBV/HCV carrier mothers vs the risk in those who were born to noncarriers. Childhood GI morbidities were predefined based on ICD-9 codes, as recorded in hospital medical files. Children with congenital malformations and multiple gestations were excluded from the analysis. A Kaplan-Meier survival curve was constructed to compare the cumulative GI morbidities over time, and a Cox proportional hazards model was used to control for confounders.

RESULTS

During the study period (1991-2014), 242 342 newborns met the inclusion criteria: 771 (0.3%) were born to HBV/HCV mothers and 241 571 (99.7%) were not. The median follow-up was 10.51 years (0-18 years). Offspring to HBV/HCV mothers had a higher incidence of GI diseases (9.3% vs 5.4%, OR = 1.82; 95% CI 1.43-2.32; Kaplan-Meier log-rank = 0.001). The increased risk remained significant in the Cox proportional hazards models, which adjusted for gestational age, mode of delivery and pregnancy complications (adjusted HR = 2.26, 95% CI: 1.79-2.85; P < .001).

CONCLUSION

Maternal HBV or HCV carrier status is an independent risk factor for long-term the GI morbidity of offspring.

Maternal HBeAg positivity and viremia associated with umbilical cord blood hepatitis B viremia

BACKGROUND

Hepatitis B (HBV) transmission may result from in utero transmission. We aimed to determine the correlation between maternal serum and umbilical cord blood HBV DNA levels in infants delivered by chronic HBV-infected mothers and to describe the effect of cord blood viremia on vertical transmission.

METHODS

A prospective cohort of 92 chronic HBV-infected mother-and-child pairs recruited over three years was analyzed. Maternal and cord blood were tested for HBV DNA by real-time PCR. Standard immunoprophylaxis with both active and passive immunization was administered to all infants. Serological testing was performed on all infants at 9 months of age.

RESULTS

Moderate positive correlation of the maternal HBV DNA with cord blood HBV DNA was demonstrated (r² = 0.521, p = <0.001). HBeAg +ve mothers were younger with higher HBV and cord viremia. At 9 months of age, one infant was infected. Infants delivered by HBeAg positive mothers and mothers with high HBV DNA of more than 6 LOG IU/mL (1 x 10⁶ IU/mL) have increased relative risk of cord blood viremia.

CONCLUSIONS

Maternal HBV DNA and presence of HBeAg were positively correlated to cord blood HBV DNA in infants delivered by chronic HBV-infected mothers. Our data suggest that reducing maternal viremia during the antenatal period may help to reduce cord blood viremia.

Study of the distribution of hepatitis B immunoglobulin in pregnant mice using small-animal imaging technology

BACKGROUND

The safety and necessity of hepatitis B immunoglobulin (HBIG) in preventing the mother-to-child transmission of hepatitis B virus (HBV) are still controversial because of its unclear mechanism of action and the inconsistent injection programs used during gestation.

OBJECTIVES

This study aimed to show the dynamic transportation and distribution of HBIG in the maternal body and to provide evidence for its clinical efficacy in preventing mother-to-child HBV transmission.

STUDY DESIGN

Pregnant mice were injected with Cy7-labeled mouse anti-human monoclonal hepatitis B surface antibodies through the tail vein. In vivo imaging technology was used to observe the dynamic transportation and distribution of HBIG in the pregnant mice.

RESULTS

HBIG fluorescence signals were higher in the uterus than in the liver, spleen, and kidneys. Fluorescence signals in the uterine region were obviously higher at the third trimester than at early and mid pregnancy.

CONCLUSIONS

HBIG is gradually deposited in the mouse placenta during pregnancy, with the phenomenon being more significant in the third trimester.

Cellular and molecular mechanisms of viral infection in the human placenta

The placenta is a highly specialized organ that is formed during human gestation for conferring protection and generating an optimal microenvironment to maintain the equilibrium between immunological and biochemical factors for fetal development. Diverse pathogens, including viruses, can infect several cellular components of the placenta, such as trophoblasts, syncytiotrophoblasts and other hematopoietic cells. Viral infections during pregnancy have been associated with fetal malformation and pregnancy complications such as preterm labor. In this minireview, we describe the most recent findings regarding virus-host interactions at the placental interface and investigate the mechanisms through which viruses may access trophoblasts and the pathogenic processes involved in viral dissemination at the maternal-fetal interface.

Hepatitis B Management in the Pregnant Patient: An Update

Chronic hepatitis B is a worldwide disease, with significant burden on health care systems. While universal vaccination programs have led to an overall decrease in incidence of transmission of hepatitis B, unfortunately, there remain large areas in the world where vaccination against hepatitis B is not practiced. In addition, vertical transmission of hepatitis B persists as a major concern. Hepatitis B treatment of the pregnant patient requires a thorough assessment of disease activity and close monitoring for flares, regardless of initiation of antiviral therapy. We discuss, in this article, the current and emergent strategies which aim to reduce the rate of transmission of hepatitis B from the pregnant mother to the infant and we review the updated guidelines regarding management of liver disease in pregnant women with hepatitis B.

Serological positive markers of hepatitis B virus in femoral venous blood or umbilical cord blood should not be evidence of in-utero infection among neonates

Background

Maternal-infant transmission of hepatitis B virus(HBV) occurs even after passive-active immunization. Some scholars speculate that in-utero infection may be the main cause of immunoprophylaxis failure. However, there is a lack of evidence about the possible occurrence periods of perinatal transmission.

Methods

From 2008 to 2012, 428 pairs of HBsAg-positive mothers and neonates were enrolled and 385 infants aged 8–12 months were followed. HBV markers (HBsAg, anti-HBs, HBeAg, anti-HBe, anti-HBc, HBV-DNA) were performed on all subjects.

Results

Of mothers who were positive for HBsAg, HBeAg, HBV-DNA, 35.1 %, 94.3 %, 12.7 % of their neonates were positive for those indices, respectively. Neonates’ mean titers of those indices were significantly lower than their mothers’. There were no significant differences in rates of positivity and mean titers of anti-HBe and anti-HBc between neonates and mothers. Most of the positive indices turned negative during the follow-up period. Immunoprophylaxis failed in seventeen infants: four infants had HBV-DNA > 6 log ₁₀copies/mL both at birth and in follow-up; in six infants, mean viral load was 3.72 ± 0.17 log ₁₀copies/mLat birth and 7.62 ± 0.14 log ₁₀copies/mL at follow-up; seven infants were HBV-DNA negative at birth but were found to have > 6 log ₁₀copies/mL during follow-up. Infants that were immunoprophylaxis failures were all born to HBeAg-positive mothers with HBV-DNA > 6 log ₁₀copies/mL.

Conclusions

The placental barrier can partly prevent maternal HBsAg, HBeAg, HBV-DNA from passing through to fetus. Performing HBsAg, HBeAg, HBV-DNA once at birth can neither diagnose nor exclude maternal-infant transmission. The diagnosis of infection period depends on the dynamic changes in viral load from birth through the follow-up period but whether the infection occurred in utero, at delivery or during the neonatal period could not be determined.

Genetic variant in CXCL13 gene is associated with susceptibility to intrauterine infection of hepatitis B virus

Intrauterine infection of hepatitis B virus (HBV), which accounts for the majority of mother-to-child transmission, is one of the main reasons for the failure of combined immunoprophylaxis against the transmission. Recent studies have identified that genetic background might influence the susceptibility to intrauterine infection of HBV. We conducted this study to investigate the associations between 10 genetic variants in 9 genes (SLC10A1, HLA-DP, HLA-C, CXCR5, CXCL13, TLR3, TLR4, TLR9 and UBE2L3) of mothers and their neonates and HBV intrauterine infection. A significantly decreased risk of HBV intrauterine transmission were found among mothers who carried the rs355687 CT genotypes in CXCL13 gene compared to those with CC genotypes (OR = 0.25, 95% CI, 0.08–0.82, P = 0.022); and a marginally significantly decreased risk was also observed under the dominant model (OR = 0.34, 95% CI, 0.11–1.01, P = 0.052). Besides, neonatal rs3130542 in HLA-C gene was found to be marginally significantly associated with decreased risk of HBV intrauterine infection under the additive model (OR = 0.55, 95% CI, 0.29–1.04, P = 0.064). However, we found no evidence of associations between the remaining 8 SNPs and risk of HBV intrauterine infection among mothers and their neonates. In conclusion, this study suggested that genetic variant in CXCL13 gene was associated with susceptibility to intrauterine infection of HBV.

The clinical implications of hepatitis B virus genotypes and HBeAg in pediatrics

Although a successful vaccine against HBV has been implemented in 184 countries, eradication of hepatitis B virus (HBV) is still not on the horizon. There are over 240 million chronic carriers of HBV globally. The risk of developing chronic hepatitis ranges from >90% in newborns of hepatitis Be antigen (HBeAg)‐positive mothers, 25%–35% in children under 5 years of age and <5% in adults. HBeAg, a non‐particulate viral protein, is a marker of HBV replication. This is the only HBV antigen to cross the placenta, leading to specific unresponsiveness of helper T cells to the capsid protein and HBeAg in newborns. HBeAg is tolerated in utero and acts as a tolerogen after birth. Perinatal transmission is frequent when mothers are HBeAg‐positive, whereas it occurs less frequently when mothers are HBeAg‐negative. Sequence heterogeneity is a feature of HBV. Based on an intergroup divergence >7.5% across the complete genome, HBV is classified phylogenetically into at least nine genotypes. With between ~4% and 8% intergroup nucleotide divergence, genotypes A–D, F, H and I are classified further into subgenotypes. HBV genotypes/subgenotypes may have distinct geographical distribution and can develop different mutations in the regions of the HBV genome that code for HBeAg. These differences can be related to the role of HBV genotypes to the natural history of infection and mode of transmission. Thus genotypes/subgenotypes of HBV can be responsible for the different natural history of infection and modes of transmission in children, found in various regions of the world, where different genotypes/subgenotypes prevail. Copyright © 2016 John Wiley & Sons, Ltd.

Changes in the prevalence of HBV infection in pregnant women in Turkey between 1995 and 2015: a 20-year evaluation

OBJECTIVE

To determine changes in hepatitis B virus (HBV) prevalence across three different time periods in pregnant women.

METHODS

This was a retrospective study of pregnant women attending four healthcare centres between January 1995 and May 2015. Data for serum hepatitis B surface antigen (HBsAg) and anti-HBs levels were collected from routine antenatal screening records. The 20-year study was divided into three periods: 1995-2001, 2002-2008 and 2009-2015. The results are presented by the women's age and gravidity as possible determinants of HBV infection.

RESULTS

7605 pregnant women (56.0% primigravidae) (mean age 23.4±4.8 years) were tested for markers of HBV infection. 3010 pregnant women were screened between 1995 and 2001, 2995 between 2002 and 2008, and 1600 between 2009 and 2015. The overall prevalence of HBsAg and anti-HBs positivity in the 7605 pregnant women was 1.5% (n=114) and 11.5% (n=877), respectively. Regarding temporal change in the prevalence of HBV markers, HBsAg decreased significantly from 2.6% to 0.8% (p<0.01), while anti-HBs increased significantly from 9.5% to 17.5% (p<0.01), between the first and last study periods. Multigravidae and older women had higher HBsAg and anti-HBs positivity compared to primigravidae.

CONCLUSIONS

The data suggest that the prevalence of HBsAg positivity is gradually decreasing among pregnant women, while the level of HBsAg antibody seropositivity is lower than expected. HBV carrier rate increases with increasing age and gravidity. In addition to the national HBV immunisation programme, the prevention of perinatal transmission should also be prioritised to decrease the HBV pool of infection.

Management of mother-to-child transmission of hepatitis B virus: Propositions and challenges

Chronic hepatitis B virus (HBV) infection due to mother-to-child transmission (MTCT) during perinatal period remains an important global health problem. Despite standard passive-active immunoprophylaxis with hepatitis B immunoglobulin (HBIG) and hepatitis B vaccine in neonates, up to 9% of newborns still acquire HBV infection, especially these from hepatitis B e antigen (HBeAg) positive mothers. Management of HBV infection in pregnancy still need to draw careful attention because of some controversial aspects, including the failure of passive-active immunoprophylaxis in a fraction of newborns, the effect and necessity of periodical hepatitis B immunoglobulin (HBIG) injection to the mothers, the safety of antiviral prophylaxis with nucleoside/nucleotide analogs, the benefit of different delivery ways, and the safety of breastfeeding. In this review, we highlight these unsettled issues of preventive strategies in perinatal period, and we further aim to provide an optimal approach to the management of preventing MTCT of HBV infection.

Unsolved problems and future perspectives of hepatitis B virus vaccination

Hepatitis B virus (HBV) infection is still a serious worldwide problem, and vaccination is the most effective strategy for primary prevention of the infection. Although universal vaccination may be required for total eradication, several countries, including Japan, have not yet adopted universal vaccination programs. Some individuals are non-responders to HBV vaccine and several mechanisms responsible for their poor response have been proposed. To overcome non-response, third generation vaccines with pre-S proteins have been developed. These vaccines have shown better anti-HBs responses and may also be effective in preventing infection by HBV with S mutant. Improvement of vaccine efficacy by intradermal administration, or co-administration with cytokines or adjuvants, may also be effective in non-responders. The necessity, timing and method of booster vaccination in responders with decreased anti-HBs responses, and effective vaccination against S-mutant HBV, are issues requiring resolution in the global prevention of HBV infection.

Study of the relationship in pregnant women between hepatitis B markers and a placenta positive for hepatitis B surface antigen

AIMS

A placenta with hepatitis B virus (HBV) is one of the main reasons for transplacental transmission during pregnancy. This study aims to explore the factors influencing the presence of hepatitis B surface antigen (HBsAg) in the placenta and the synergistic effect of these factors.

METHODS

A total of 155 placentae and blood specimens were collected from HBsAg-positive mothers and their newborns. HBsAg in placenta was detected using the immunohistochemistry method. HBV serum markers were detected using enzyme-linked immunosorbent assay (ELISA) and polymerase chain reaction (PCR) methods.

RESULTS

The results showed that hepatitis B e antigen (HBeAg) positive, or HBV DNA positive status, is significantly associated with an HBsAg-positive placenta. A synergistic effect was present. The hazard ratio for a HBsAg-positive placenta in mothers with HBeAg and HBV DNA was 1.97 times higher than the sum of the independent relative risk of each separate effect (synergy index, S=1.97). There was a statistically significant association between HBsAg in newborns and HBsAg in placenta, and the risk of newborns with HBsAg was greater (odds ratio values 3.33 and 5.31, respectively) when placental cells close to the fetal side were HBsAg positive.

CONCLUSIONS

Being positive for HBeAg and/or HBV DNA are significant risk factors for HBsAg in the placenta. HBsAg can pass through the placenta via cellular transfer, possibly contributing to transplacental transmission.

Liver function tests in viremic and nonviremic chronic hepatitis B virus-infected pregnant women: importance of alanine aminotransferase/sodium ratio

The major risk factor of perinatal transmission of Hepatitis B virus (HBV) infection is the level of maternal HBV-deoxyribonucleic acid (DNA) during the third trimester of pregnancy. The primary aim of this study was to evaluate the hematological and biochemical status in Hepatitis B e-antigen (HBeAg)-negative chronic HBV-infected pregnant women and to correlate the findings with the presence or absence of viremia. Ninety-five consecutive chronic HBV-infected pregnant women were evaluated between the 28th and 32nd week of gestation. Viral load was determined by using the COBAS TaqMan HBV test. Sixty-nine women were evaluated and 14 of them exhibited HBV-DNA levels higher than 2000 IU·ml. In this study, viremic women exhibited significantly higher alanine aminotransferase (ALT), creatinine, and uric acid values as well as significantly lower white blood cell count compared with nonviremic women. There was also a significant statistical difference concerning ALT/sodium ratio between viremic and nonviremic women (0.20 ± 0.22 vs. 0.10 ± 0.09, respectively, p= .024). The optimal cutoff points discriminating those women with a high probability to have detectable serum HBV-DNA were 0.092 for ALT/sodium ratio (sensitivity = 73.0%, specificity = 61.5%, area under the receiver operating characteristic curve [AUC] = 71.05%) and 12.8 IU/L for ALT (sensitivity = 73.0%, specificity = 63.0%, AUC = 72.2%). Chronic HBV-infected pregnant women with ALT/sodium ratio ≥ 0.11 had the higher probability of having serum HBV-DNA levels higher than 2000 IU/ml (sensitivity = 76.92%, specificity = 58%, AUC = 62.38%). Presence of HBV-DNA in maternal blood during the third trimester of pregnancy is significantly associated with maternal serum ALT levels in HBeAg-negative chronic HBV-infected pregnant women. Women with an ALT/sodium ratio greater than 0.092 have the higher probability of HBV-DNA presence in maternal blood whereas an ALT/sodium ratio greater than 0.11 could discriminate those women with HBV-DNA levels higher than 2000 IU/ml.

Evaluation of neonatal Toll-like receptors 3 (c.1377C/T) and 9 (G2848A) gene polymorphisms in HBV intrauterine transmission susceptibility

To investigate whether single nucleotide polymorphisms (SNPs) in Toll-like receptors (TLRs) 3 and 9 affect the susceptibility of hepatitis B virus (HBV) intrauterine transmission, we genotyped 399 neonates for TLR3 (c.1377C/T) [rs3775290] and TLR9 (G2848A) [rs352140] using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). A femoral venous blood sample was obtained from these subjects. Hepatitis B surface antigen (HBsAg) and hepatitis B e antigen (HBeAg) were measured using chemiluminescence immunoassay kits and hepatitis B virus DNA (HBV DNA) levels were determined by fluorescence quantitative PCR assay. Our results showed that when adjusting for maternal HBeAg, maternal HBV DNA and mode of delivery, allele 'T' for SNP c.1377C/T was significantly associated with HBV intrauterine transmission susceptibility [adjusted OR (aOR) 0.55, 95% confidence interval (CI) 0.34-0.91, P = 0.020] and the TT genotype decreased the risk of HBV intrauterine transmission (aOR 0.28, 95% CI 0.09-0.91, P = 0.033). Allele 'A' for SNP G2848A was significantly associated with HBV intrauterine transmission susceptibility (aOR 0.62, 95% CI 0.39-1.00, P = 0.048) and the GA genotype protected neonates from HBV intrauterine transmission (aOR 0.45, 95% CI 0.22-0.93, P = 0.031). The TLR3 (c.1377C/T) and TLR9 (G2848A) polymorphisms may be relevant for HBV intrauterine transmission susceptibility, although the reduction in risk to HBV intrauterine transmission is modest and the biological mechanism of the observed association merits further investigation.

Potential roles of placental human beta-defensin-3 and apolipoprotein B mRNA-editing enzyme catalytic polypeptide 3G in prevention of intrauterine transmission of hepatitis B virus

Approximately 5% of newborns were infected by hepatitis B virus (HBV) via intrauterine transmission and this is the main reason for high prevalence of HBV in endemic regions. However, the mechanisms by which intrauterine transmission is avoided in most cases remain elusive and placental natural anti-microbial factors may play a role in the prevention of HBV intrauterine transmission. The expression levels of human β-defensin-3 (HBD-3), apolipoprotein B mRNA-editing enzyme catalytic polypeptide 3G (A3G) and mannose binding lectin (MBL) were determined in the placenta of 30 HBV-seronegative pregnant women (controls), 7 HBV-seropositive pregnant women with infants infected via intrauterine transmission (infected group) and 30 HBV-seropositive pregnant women with non-infected infants (non-infected group). The expression of HBD-3, A3G, and MBL of placental trophoblast cell line Swan71 was determined after exposed to HBV. There were significant differences in placental HBD-3 and A3G levels among three groups, but the expression of MBL did not significantly differ. The expressions of HBD-3 and A3G were higher in non-infected group than controls and infected group, but not significantly different between infected group and controls. The exposure to HBV increased significantly the expression of HBD-3, A3G, and MBL by Swan 71. It may be concluded HBV up-regulates HBD-3 and A3G expression in vivo and in vitro in placental trophoblast and lack of this up-regulation is possibly associated with intrauterine transmission of HBV.

Prevention of Perinatal Hepatitis B Virus Transmission

Hepatitis B virus (HBV) infection, the most common form of chronic hepatitis worldwide, is a major public health problem affecting an estimated 360 million people globally. Mother-to-child transmission (MTCT) is responsible for more than one third of chronic HBV infections worldwide. An estimated 15%-40% of persons chronically infected develop HBV-related complications, such as cirrhosis and hepatic carcinoma, and 25% die from these complications. MTCT can occur during pregnancy or during delivery. Screening pregnant women for HBV infection, providing infant postexposure prophylaxis, and maternal treatment with antiviral medications are strategies for reducing MTCT transmission rates and the global burden of new chronic HBV infections. Administration of hepatitis B immune globulin (HBIG) and hepatitis B (HepB) vaccine within 24 hours of birth, followed by completion of the vaccine series, is 85%-95% efficacious for prevention of MTCT. Despite timely post-exposure prophylaxis, MTCT occurs in 5%-15% of infants. Hepatitis B surface antigen (HBsAg) positive, hepatitis e antigen (HBeAg) positive mothers with HBV DNA level ≥10(6) copies/mL (>200 000 IU/mL) are at greatest risk of transmitting HBV to their infants. Consensus recommendations and evidence-based guidelines for management of chronic HBV infection and screening of pregnant women have been developed. The safety and efficacy of antiviral drug use during pregnancy are areas of ongoing research. Substantial advances have been achieved globally in reducing MTCT, but MTCT remains an ongoing health problem. Attaining a better understanding of the mechanisms of MTCT, implementing existing policies on maternal screening and infant follow-up, and addressing research gaps are critical for further reductions in MTCT transmission.

Immunoprophylaxis failure against vertical transmission of hepatitis B virus in the Chinese population: a hospital-based study and a meta-analysis

BACKGROUND

Despite effective immunoprophylaxis, vertical transmission of hepatitis B virus (HBV) from infected mothers still occurs. This study aimed to provide an estimate of the prevalence of immunoprophylaxis failure and evaluate associated risk factors.

METHODS

A hospital-based prospective study was conducted from June 1, 2008, to June 30, 2012. In this prospective study, 294 HBsAg-positive mothers were followed up from their first prenatal care visits until their infants completed the proposed vaccination schedule. Further, studies providing prevalence rates of immunoprophylaxis failure in the Chinese population were identified from electronic databases and were collected for a meta-analysis.

RESULTS

In the prospective study, 16 (5.44%) infants developed HBV infection despite passive-active immunoprophylaxis. Twelve of these infants were born to HBeAg-positive mothers with cord blood that was positive for HBV DNA. After adjusting for maternal and infant factors, HBV DNA detectable in cord blood (odds ratio: 22.32, 95% confidence interval: 4.00-124.47) was associated with a significantly greater risk of immunoprophylaxis failure. The prospective study and 23 previous studies were included in the meta-analysis, constituting a total of 7561 Chinese participants. The overall estimated rates of immunoprophylaxis failure for infants with HBsAg-positive and HBeAg-positive mothers were 4.87% and 9.66% respectively.

CONCLUSIONS

Immunoprophylaxis failure is an extensive problem, and further studies should design and assess novel strategies for the prevention of immunoprophylaxis failure, especially for cases involving HBeAg-positive mothers and infants with cord blood that is positive for HBV DNA.

Vertical transmission of hepatitis B virus: challenges and solutions

More than 240 million people worldwide are chronically infected with hepatitis B virus (HBV). Mother-to-child transmission remains the most important mechanism of infection in countries with a high prevalence of HBV. Universal screening of all pregnant women, at-birth prophylaxis with specific anti-HBV immune globulin, as well as HBV vaccination for newborns of infected mothers are effective in reducing the risk of vertical transmission. However, in cases of a high viral load and hepatitis B e antigen positivity, there is a residual risk of HBV transmission to the newborn despite prophylaxis. This review focuses on the above-indicated strategies and on the efficacy and safety of antiviral drugs administered during the third trimester of pregnancy.

Frequencies of dendritic cells and Toll-like receptor 3 in neonates born to HBsAg-positive mothers with different HBV serological profiles

To investigate the frequencies of dendritic cells (DCs) and Toll-like receptor 3 (TLR3) in neonates of HBsAg-positive mothers with different HBV serological profiles, we conducted a study in Taiyuan, China. The study included 144 HBsAg-positive mothers and their neonates. The frequencies of DCs and TLR3 were determined using four-colour flow-cytometric analysis. DC and TLR3 frequencies were not related to HBV intrauterine transmission, maternal HBeAg positivity, maternal HBV DNA positivity and HBeAg/HBV DNA double-positivity. The plasmacytoid dendritic cell (pDC) frequencies in neonates whose maternal HBV DNA was >5 × 107 copies/ml decreased significantly compared to that in neonates whose maternal HBV DNA was ⩽5 × 107 copies/ml (Z = - 2·170, P = 0·03) or whose maternal HBV DNA was negative (Z = - 1·981 P = 0·048). This study suggests that neonatal pDC frequencies decrease when maternal HBV DNA loads are >5 × 107 copies/ml.

Risk factors for intrauterine infection with hepatitis B virus

OBJECTIVE

To investigate risk factors for hepatitis B virus (HBV) intrauterine infection.

METHODS

Peripheral blood samples and clinical data were collected from 174 pregnant women who were positive for hepatitis B surface antigen (HBsAg). Their 176 neonates received an active-passive immunization schedule at 0, 1, and 6 months. Blood samples from the infants, collected before immune prophylaxis administration, were tested for HBV markers and HBV DNA.

RESULTS

The intrauterine infection rate at 6 months after birth was 5.1%. Maternal HBV DNA positivity (OR 11.362; 95% CI, 1.389-92.931), hepatitis B e antigen (HBeAg) positivity (OR 7.278; 95% CI, 1.734-30.538), and thalassemia minor (OR 15.619; 95% CI, 2.239-108.964) were associated with intrauterine infection. The intrauterine infection rate for mothers with 10(5) copies/mL of serum HBV DNA or more was 18.2%, compared with 0.8% for mothers with less than 10(5) copies/mL.

CONCLUSION

A positive HBsAg test at 24 hours and/or 1 month of age followed by a positive test at 6 months is an objective and comprehensive criterion for the diagnosis of HBV intrauterine infection. Maternal HBV DNA positivity (especially 10(5) copies/mL of HBV DNA or more), HBeAg positivity, and thalassemia minor are risk factors for HBV intrauterine infection.

Measures to reduce mother-to-child transmission of Hepatitis B virus in China: a meta-analysis

BACKGROUND

Mother-to-child transmission (MTCT) is the main mode of spread of hepatitis B virus (HBV) in China. We performed a meta-analysis to compare the effects of three measures for prevention of MTCT.

METHODS

A meta-analysis was performed on randomized controlled trials and non-randomized studies comparing the index of MTCT among five groups of pregnant women: hepatitis B immunoglobulin (HBIG) administration, antiviral treatment, placebo, elective caesarean section, and vaginal delivery.

RESULTS

Compared with the control group, the incidence of HBV intrauterine infection (RR = 0.42, 95 % CI 0.27-0.64, P < 0.0001) and the number of chronic hepatitis B (CHB) infants (RR = 0.44, 95 % CI 0.32-0.61, P < 0.00001) were lower in the HBIG administration group. In the antiviral treatment group, serum HBV DNA levels were lower (MD = -4.01, 95 % CI -5.07 to -2.94, P < 0.00001) at the time of delivery, and normalization of ALT levels was better (RR = 1.11, 95 % CI 1.06-1.17, P < 0.0001). Infant serum HBsAg positivity (RR = 0.45, 95 % CI 0.22-0.91, P = 0.03) and incidence of infant HBV transmission RR = 0.06, 95 % CI 0.01-0.24, P < 0.0001) were reduced in antiviral the treatment group. Infant serum anti-HBs positivity at birth (RR = 1.24, 95 % CI 0.89-1.74, P = 0.2) or at 6-7 months (RR = 0.98, 95 % CI 0.86-1.11, P = 0.73) was not significantly different between the caesarean section and vaginal delivery groups. The incidence of infant CHB infection may have been higher in the vaginal delivery group (RR = 2.20, 95 % CI 1.02-4.74, P = 0.04).

CONCLUSIONS

Administration of HBIG or antiviral therapy to HBV carrier mothers during pregnancy is effective in reducing MTCT.