Mother-to-infant transmission of hepatitis B virus: challenges and perspectives

Viral Hepatitis in Pregnant Mexican Women: Its Impact in Mother-Child Binomial Health and the Strategies for Its Eradication

Viral hepatitis is the main cause of infectious liver disease. During pregnancy, a risk of vertical transmission exists both during gestation and at birth. HAV, HBV, and HCV might progress similarly in pregnant and non-pregnant women. In this study, we found a prevalence of 0.22% of viral hepatitis in pregnant women, with a light preponderance of HCV over HAV and HBV. Here, it was observed that acute HAV infection is more symptomatic and has higher risks for the mother and fetus, in a similar manner to what has been reported for HEV. Histopathological alterations were observed in all except one placenta, indicating that it is an important tissue barrier. Regarding the Mexican strategies for viral hepatitis eradication, success may be related to vaccination at birth, whereas for HCV, the national program for eradication is aimed at treating the infection via direct-acting antiviral agents. The HBV strategy has positively impacted pregnant women and their children, diminishing the risk of vertical transmission. The HCV strategy is still in its early years, and it is expected to be just as successful. For acute hepatitis, HAV and HEV, programs promoting hand washing and those aimed at providing clean food and water are applicable as preventive strategies, alongside other programs such as vaccination.

Functional cure is associated with younger age in children undergoing antiviral treatment for active chronic hepatitis B

BACKGROUND AND AIMS

Functional cure is difficult to achieve using current antiviral therapies; moreover, limited data are available regarding treatment outcomes in children. This retrospective study aimed to assess the frequency of functional cure among children undergoing antiviral treatment for active chronic hepatitis B (CHB).

METHODS

A total of 372 children aged 1-16 years, with active CHB were enrolled and underwent either nucleos(t)ide analog monotherapy or combination therapy with interferon-α (IFN-α) for 24-36 months. All children attended follow-up visits every 3 months. Functional cure was defined as evidence of hepatitis B virus (HBV) DNA loss, circulating hepatitis B e antigen (HBeAg) loss/seroconversion, and hepatitis B surface antigen (HBsAg) loss.

RESULTS

After 36 months of antiviral treatment and/or follow-up visits, children with CHB aged 1- < 7 years exhibited higher rates of HBV DNA clearance, HBeAg seroconversion, and HBsAg loss than CHB children ≥ 7-16 years of age (93.75% versus [vs.] 86.21% [p < 0.0001]; 79.30% vs. 51.72% [p < 0.0001]; and 50.78% vs. 12.93% [p < 0.0001], respectively). Longitudinal investigation revealed more rapid dynamic reduction in HBV DNA, HBeAg, and HBsAg levels in children aged 1-7 years than in those aged ≥ 7-16 years with CHB. According to further age-stratified analysis, HBsAg loss rates were successively decreased in children with CHB who were 1- < 3, 3- < 7, 7- < 12, and 12-16 years of age (62.61% vs. 41.13% vs. 25.45% vs. 1.64%, respectively; p < 0.0001) at 36 months. In addition, baseline HBsAg level < 1,500 IU/mL was found to favor disease cure among these pediatric patients. No serious adverse events were observed throughout the study period.

CONCLUSION

Results of the present study demonstrated that children aged 1- < 7 years, with active CHB can achieve a high functional cure rate by undergoing antiviral therapy compared to those aged ≥ 7 years, who undergo antiviral therapy. These data support the use of antiviral treatment at an early age in children with CHB. However, future prospectively randomized controlled trials are necessary to validate the findings of this study.

Association of Dipeptidyl Peptidase-4 Inhibitors Use with Reduced Risk of Hepatocellular Carcinoma in Type 2 Diabetes Patients with Chronic HBV Infection

Previous studies have indicated that HBV infection and T2DM are the factors that increase the risk of developing HCC. The experimental evidence has shown that antiglycemic agents may reduce the risk of HCC. However, the effect of dipeptidyl peptidase-4 inhibitors (DPP-4 inhibitors) on the risk of HCC in T2DM patients with chronic HBV infection remains unclear. In this retrospective cohort study, we extracted patients with T2DM and chronic HBV infection from the National Health Insurance Research Database (NHIRD) in Taiwan. The cases were divided into DPP-4 inhibitors use and non-use groups, according to whether they received DPP-4 inhibitors treatment, and the risk of HCC was compared between the two groups. At the end of the follow-up, approximately 2.33% of DPP-4 inhibitors users had received an HCC diagnosis compared with 3.33% of non-DPP-4 inhibitors users (p < 0.0001). After multivariate adjustment, DPP-4 inhibitors users showed a significant reduction in HCC risk (adjusted hazard ratios (aHRs): 0.53; 95% confidence intervals (CIs): 0.44-0.65). In conclusion, this population-based retrospective cohort study indicated that, in T2DM patients with chronic HBV infection, the use of DPP-4 inhibitors significantly reduced the risk of developing HCC compared with non-DPP-4 inhibitors use.

Hepatocyte proliferation favours viral clearance in young children with chronic hepatitis B virus infection

AIM

The aim of this study is to explore the correlation between hepatocyte proliferation and hepatitis B virus (HBV) clearance in young children with chronic HBV infection.

METHODS

We collected liver biopsy samples and clinical data corresponding to paediatric patients with chronic HBV infection. Ki-67 expression in liver tissues was evaluated by immunohistochemical staining.

RESULTS

Eighteen patients were included and were divided into two groups based on different antiviral outcomes. Group I achieved hepatitis B surface antigen (HBsAg) loss within 48 weeks. Group II did not develop seroconversion from hepatitis B e (HBe) antigen to anti-HBe after 48 weeks. There were 10 patients in Group I and 8 in Group II, respectively. Demographical data and baseline virological and biochemical characteristics in serum across Group I and Group II were not statistically different. Histologically, mean Ki-67 expression index in Group I was 15%, while the mean index in Group II was 5%. There was a significant difference between the two groups (p < 0.01).

CONCLUSION

High Ki-67 expression can contribute to viral clearance in young children with chronic HBV infection. This is the first confirmation of the association between hepatocyte proliferation and HBV clearance in vivo and has implications for novel therapeutic strategies against hepatitis B.

Follow-Up of Newborns with Hepatitis B Antigenemia

INTRODUCTION

There is a need for data to evaluate hepatitis B antigenemia in newborns of mothers with hepatitis B virus (HBV) infection. This study aims to investigate this.

METHODS

Newborns with positive serum hepatitis B surface antigen (HBsAg) and/or e antigen (HBeAg) were enrolled in the study.

RESULTS

One hundred and one newborns from 98 HBV-infected mothers were included. Median maternal serum HBV DNA level was 23,200 IU/mL at delivery. Among the newborns, 48 were boys and 53 were girls. Mean birth weight was 3190.5 g. Twenty-one newborns had concurrent seropositive HBsAg and HBeAg, nine had seropositive HBsAg and seronegative HBeAg, and 71 had seronegative HBsAg and seropositive HBeAg. Eight newborns had detectable serum HBV DNA. In the follow-up, serum HBsAg and HBeAg in the newborns with undetectable HBV DNA became negative before 6 months of age. Two infants with detectable HBV DNA were diagnosed with immunoprophylaxis failure, one of whom developed active hepatitis at 3 months of age. Liver biopsy in this case showed significant interface hepatitis, fibrous septa formation, and expansion of portal areas with occasional bridging fibrosis.

CONCLUSIONS

Concurrent HBV viremia and antigenemia in newborns of HBV-infected mothers requires attention, while antigenemia without viremia is often transient.

Hepatitis B Viral Markers in the Human Milk of HBsAg-Positive Mothers: An Observational Study

BACKGROUND

Quantification of viral antigens and viral loads in human milk samples from mothers infected with hepatitis B virus is largely unknown.

RESEARCH AIM

The aim of the study was to quantitatively measure the levels of viral antigens and deoxyribonucleic acid of hepatitis B virus in human milk from mothers infected with hepatitis B virus.

METHODS

Fifty-five pairs of milk and serum samples from mothers with positive hepatitis B surface antigen, including 11 hepatitis B e antigen positive, were quantitatively tested to measure viral antigens by microparticle enzyme immunoassay and viral loads by real-time polymerase chain reaction assay.

RESULTS

The median level of hepatitis B surface antigen in the human milk samples of mothers with positive or negative hepatitis B e antigen was each lower than that in the sera, respectively (1.10 vs. 4.32 log₁₀ IU/ml, t = 10.693, p < .001; -0.77 vs. 2.53 log₁₀ IU/ml, t = -25.135, p < .001). The titers of hepatitis B surface antigen or hepatitis B e antigen in the human milk samples were each correlated with that in maternal serum. The detectable level of deoxyribonucleic acid of hepatitis B virus in human milk ranged from 1.42-5.27 log₁₀ IU/ml, whereas that in maternal sera was 1.44-8.66 log₁₀ IU/ml. The viral level in human milk was not correlated with that in maternal circulation.

CONCLUSION

The present study data illustrate the relatively low titers of viral markers in the milk of mothers with positive hepatitis B surface antigen.

The Role of Autophagy in the Mother-to-Child Transmission of Pregnant Women With a High Level of HBV DNA

Background

Mother-to-child transmission (MTCT) is the most common propagation mode of hepatitis B virus (HBV) transmission. Exploring the mechanisms of HBV MTCT is the key to protect infant from infection. In this study, we aim to clarify the important role of autophagy complicated in HBV MTCT.

Methods

A total of 169 placental samples were collected in this study, includes 144 HBV positive pregnant women and 25 normal pregnant women. In vitro, JEG-3 cells were treated with serum contained different HBV viral loads. Electron microscope was used to observed the number of autophagosome. RT-qPCR and western blotting were used to measure the expression level of autophagy relative genes and proteins respectively. Immunofluorescence was used to analyzed the expression of LC-3 of the frozen section of placental tissue.

Results

According to the number of autophagosomes and the expression level of autophagic genes mRNA and protein, autophagy was increased in HBV maternal placenta. Among the control, low viral load, medium viral load and high viral load groups, autophagy was significantly up-regulated with the increase of HBV viral loads. Also, autophagy was increased in the HBeAg positive pregnant women compared with their HBeAg negative counterparts. Also, autophagy in infant-infected group was up-regulated compared with infant-uninfected group. In vitro, choriocarcinoma JEG-3 cells were treated with the different HBV viral loads or different time incubation, the mRNA and protein of autophagy related genes was maximum expression in the medium viral load or treatment in a short period, but decreased in the high viral load treatment or with long-term HBV exposure.

Conclusion

Our study determines the high levels of viremia could be the cause of both increase autophagy activities and MTCT. Autophagy was significantly up-regulated in pregnant women with high viral load or HBeAg positive, which plays an important part in the HBV MTCT.

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.

HBxAg promotes HBV replication and EGFR activation in human placental trophoblasts

Hepatitis B virus (HBV) infection is a global epidemic. The main transmission route of chronic HBV infection is from mother to child, yet the mechanisms underlying HBV intrauterine infection remain unclear. In the present study, the effect and the mechanism underlying hepatitis B virus X antigen (HBxAg) on HBV replication and EGFR activation in trophoblasts was investigated. Serum samples from pregnant women with HBV infection were used to infect trophoblasts and HBxAg expression was detected using ELISA. HBV plasmids carrying either full length hepatitis B virus X (HBx) or HBx with a deletion mutation (ΔHBx) were transfected into trophoblasts and expression levels of HBV DNA, hepatitis B e-antigen and pregenomic (pg)RNA, and structural maintenance of chromosomes (Smc) 5/6 were assessed. The association between HBx and EGFR promoters was characterized using a luciferase reporter assay and EGFR/PI3K/phosphorylated (p)-AKT expression and apoptosis rate were also monitored. The results of the present study indicated that HBxAg expression increased with the increasing titre of HBV DNA (P<0.05). Compared with the wild-type group, the amount of HBV DNA in the supernatant and cells was significantly reduced (P<0.05) in the ΔHBx group and the intracellular HBeAg and pgRNA levels were also significantly decreased (P<0.05). In addition, Smc5/6 expression was also significantly decreased (P<0.05) when the intracellular HBx protein was expressed compared with mock-transfected cells. Co-transfection of HBx and EGFR promoter plasmids in JEG-3 and HTR-8 cells significantly elevated EGFR promoter driven luciferase expression relative to the control group (P<0.01). In EGFR overexpressing cells, the expression of PI3K/p-AKT was significantly increased, whereas the apoptosis rate was significantly decreased (P<0.05). These results were reversed in the EGFR-knockdown group. In conclusion, the present study demonstrated that HBx promotes HBV replication in trophoblasts via downregulation of Smc5/6, activates the EGFR promoter and inhibits trophoblast apoptosis via the PI3K/p-AKT downstream signalling pathway, thereby increasing the risk of HBV intrauterine infection.

Clinical, Pathological and Genetic Characteristics of Pediatric Hepatocellular Carcinoma Associated with Hepatitis B Virus Infection

Introduction

Hepatocellular carcinoma (HCC) remains the major challenge in the management of patients with hepatitis B virus (HBV) infection. To date, limited studies have been done on pediatric HBV-associated HCC specifically.

Methods

Pediatric patients younger than 16 years with HBV-associated HCC were included in the study. HBV integration detection was performed using a high-throughput viral integration detection (HIVID) method.

Results

Among the 13 included pediatric patients, boys predominated (10, 76.9%). The median age at diagnosis of HCC was 13 years and the youngest age was 6 years. Nine patients had initially seronegative hepatitis B e antigen (HBeAg) and 4 had seropositive HBeAg. All patients had cirrhosis and elevated alpha-fetoprotein. Splenomegaly was present in all patients. Intrahepatic HBsAg was not detected in any tumor tissues from 5 patients who underwent biopsy or excision, while it was positive in all matched non-tumor tissues. In the tumor and matched non-tumor tissues from 3 individuals, HBV integration was identified except in the neoplastic specimen from 1 patient. Integration into the reported genes associated with hepatocarcinogenesis was not found in the tumor tissues from the 3 patients.

Discussion

Hypervigilance for HCC development is required in HBeAg-negative cirrhotic children. The findings based on the immunohistochemical and genetic results expand the knowledge of pediatric HCC development.

Dynamic profile of the HBeAg-anti-HBe system in acute and chronic hepatitis B virus infection: A clinical-laboratory approach

Wild-type HBV infection is followed by the blood expression of its widely known serological markers of infection, and designated as, hepatitis B virus surface antigen (HBsAg) and its antibody (anti-HBs), anti-HBc antibodies (IgM/IgG), and hepatitis B virus 'e' antigen (HBeAg) and its antibody (anti-HBe). These markers are detected as the infection develops and its kinetic behavior serves as a basis for monitoring the disorder and for diagnosing the clinical form or infection phase. Among these, the HBeAg-anti-HBe system markers demonstrate a dynamic profile whose interpretation, both in the acute or chronic HBV infection context, can offer greater difficulty to the health professionals, due to its particularities. This review offers a revisit to the markers dynamics of this system in the acute and chronic HBV infection and to the clinical and laboratory significance of its expression in these two clinical contexts.

Coronavirus disease 2019 among pregnant Chinese women: case series data on the safety of vaginal birth and breastfeeding

OBJECTIVE

To assess whether vaginal secretions and breast milk of women with coronavirus disease 2019 (COVID-19) contain severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2).

DESIGN

Single centre cohort study.

SETTING

Renmin Hospital of Wuhan University, Wuhan, Hubei province, China.

POPULATION

We studied 13 SARS-CoV-2-infected pregnant women diagnosed between 31 January and 9 March 2020.

METHODS

We collected clinical data, vaginal secretions, stool specimens and breast milk from SARS-CoV-2-infected women during different stages of pregnancy and collected neonatal throat and anal swabs.

MAIN OUTCOMES AND MEASURES

We assessed viral presence in different biosamples.

RESULTS

Of the 13 women with COVID-19, five were in their first trimester, three in their second trimester and five in their third trimester. Of the five women in their third trimester who gave birth, all delivered live newborns. Among these five deliveries, the primary adverse perinatal outcomes included premature delivery (n = 2) and neonatal pneumonia (n = 2). One of nine stool samples was positive; all 13 vaginal secretion samples, and five throat swabs and four anal swabs collected from neonates, were negative for the novel coronavirus. However, one of three samples of breast milk was positive by viral nucleic acid testing.

CONCLUSIONS

In this case series of 13 pregnant women with COVID-19, we observed negative viral test results in vaginal secretion specimens, suggesting that a vaginal delivery may be a safe delivery option. However, additional research is urgently needed to examine breast milk and the potential risk for viral contamination.

TWEETABLE ABSTRACT

New evidence for the safety of vaginal delivery and breastfeeding in pregnant women infected with SARS-CoV-2, positive viral result in a breast-milk sample.

Vertical Transmission of Severe Acute Respiratory Syndrome Coronavirus 2: A Systematic Review

OBJECTIVE

The aim of this study is to summarize currently available evidence on vertical transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2).

STUDY DESIGN

A systematic review was conducted following the guidelines of the Preferred Reporting Items for Systematic Reviews and Meta-analysis Statement.

RESULTS

A total of 22 studies comprising 83 neonates born to mothers diagnosed with coronavirus disease 2019 were included in the present systematic review. Among these neonates, three were confirmed with SARS-CoV-2 infection at 16, 36, and 72 hours after birth, respectively, by nasopharyngeal swab real-time polymerase chain reaction (RT-PCR) tests; another six had elevated virus-specific antibody levels in serum samples collected after birth, but negative RT-PCR test results. However, without positive RT-PCR tests of amniotic fluid, placenta, or cord blood, there is a lack of virologic evidence for intrauterine vertical transmission.

CONCLUSION

There is currently no direct evidence to support intrauterine vertical transmission of SARS-CoV-2. Additional RT-PCR tests on amniotic fluid, placenta, and cord blood are needed to ascertain the possibility of intrauterine vertical transmission. For pregnant women infected during their first and second trimesters, further studies focusing on long-term outcomes are needed.

KEY POINTS

· We review neonates of mothers diagnosed with coronavirus disease 2019 detected by RT-PCR.. · No direct virologic evidence of vertical transmission has been reported.. · No evidence that cesarean delivery is safer than vaginal delivery.. · More RT-PCR tests on amniotic fluid, placenta, and cord blood are recommended..

Early initiation of antiviral therapy contributes to a rapid and significant loss of serum HBsAg in infantile-onset hepatitis B

BACKGROUND & AIM

There is a paucity of data regarding antiviral therapy in hepatitis B virus (HBV)-infected infants aged <1 year who have elevated alanine aminotransferase. This study aims to assess the efficacy and safety of antiviral therapy initiated in infancy.

METHODS

A real-world cohort study was conducted from January 2010 to December 2017. HBV-infected infants under 1 year of age, with persistent elevation of alanine aminotransferase and high viral load, were recruited and divided into 2 groups. Group I included 18 infants whose parents chose to initiate antiviral therapy with lamivudine before 1 year of age. Group II included 11 infants whose parents chose to initiate antiviral therapy with interferon-α after 1 year of age and not to receive any antiviral therapies before 1 year of age. The main outcome measure was rate of serum HBV surface antigen (HBsAg) loss at month 12 of treatment.

RESULTS

There were no statistical differences between Groups I and II regarding baseline characteristics. No infants in Group II developed spontaneous HBsAg loss before 1 year of age. In Group I, the cumulative rates of HBsAg loss at month 3, 6, 9 and 12 of treatment were 39%, 67%, 78% and 83%, respectively. In Group II, the cumulative rates of HBsAg loss at month 3, 6, 9 and 12 of treatment were 18%, 27%, 27% and 36%, respectively. Statistical differences existed in the cumulative rates of HBsAg loss between the 2 groups (log-rank test, p = 0.0023). No serious adverse events occurred in the study.

CONCLUSION

Early initiation of antiviral therapy for infantile-onset hepatitis B contributes to a rapid and significant loss of HBsAg. Further trials with larger cohorts are needed to verify our results.

LAY SUMMARY

Chronicity is a serious threat to infants infected with hepatitis B. However, no treatment measure has been recommended for infantile-onset hepatitis B in current guidelines. In order to evaluate the benefit and safety of antiviral therapy in infantile-onset hepatitis B, a real-world cohort study was conducted. Long-term follow-up results showed that early initiation of antiviral therapy with lamivudine safely led to a rapid and significant loss of serum hepatitis B surface antigen in the present subset of infants with alanine aminotransferase ≥2× upper limit of normal. Further trials with larger cohorts are needed.

[Xenobiotics and pathogens in breast milk : A risk for the child?]

Although breast milk is the best diet in the first few months of life, risks can arise for the breast-fed infant. The article gives a comprehensive overview of possible risks regarding xenobiotics and pathogens in mother's milk, including medications, smoking, alcohol consumption, coffee consumption, persistent environmental contaminants and residues as well as infections.Where drug therapy is indicated, suitable medications are available for most conditions nowadays, so that prolonged nursing breaks or even weaning is not required. Long-term treatment, especially under combination therapy, needs to be examined on a case-by-case basis, however. Smoking and alcohol consumption should be avoided during the breastfeeding period, while moderate coffee consumption (up to 2 cups daily) is not of concern. The current levels of environmental contaminants and residues in breast milk are considered to be harmless to health; indeed, the body burden of dioxins considered to be critically high more than 20 years ago has been reduced by a factor of 10 to date. Among maternal infections, an human deficiency virus (HIV) infection is one of the few medical indications for weaning in countries with adequate hygiene standards.All in all, the risks of xenobiotics and pathogens in mother's milk are generally low in exclusively breastfed infants, so that there is usually no need for prolonged nursing breaks or even weaning. In only a small number of maternal conditions (certain medications, HIV infection), the infant should not be breastfed.

The association of adverse outcomes in the mother with disease progression in offspring in families with clusters of hepatitis B virus infection and unfavorable prognoses in Northwest China

To investigate the transmission routes of hepatitis B virus (HBV) in families with clusters of infection and unfavorable prognoses and to analyze the prevalence of liver cirrhosis (LC) or hepatocellular carcinoma (HCC) in the offspring of these families.Families with clusters of HBV infection and unfavorable prognoses were enrolled in the study, and general information and serum samples were collected. The prevalence of LC or HCC was compared in offspring of different genders whose parents were diagnosed with LC or HCC.This analysis comprised 102 probands with 51 siblings, 15 parents, 284 children, and 74 spouses. Interestingly, 88.2% of the siblings and 76.8% of the children of these probands were positive for hepatitis B surface antigen (HBsAg), compared with only 9.5% of the spouses (P < .001). There were 266 nuclear families from 102 clustering families. The prevalence of LC or HCC in sons (44.8%) was higher than that in daughters (8.2%; P < .05) in families with mothers with LC or HCC, but there was no difference in families with fathers with LC or HCC. Moreover, the prevalence of LC or HCC in sons from families with mothers with LC or HCC (44.8%) was higher than in the families with fathers with LC or HCC (21.0%, P = .016).The development of LC or HCC in offspring showed a greater relationship with the adverse outcomes induced by HBV infection in the mother compared with the father, and the prevalence of LC or HCC was much higher in male offspring.