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

Maternal obesity and metabolic (dysfunction) associated fatty liver disease in pregnancy: a comprehensive narrative review

INTRODUCTION

Obesity and metabolic-associated fatty liver disease (MAFLD) during pregnancy constitute significant problems for routine antenatal care, with increasing prevalence globally. Similar to obesity, MAFLD is associated with a higher risk for maternal complications (e.g. pre-eclampsia and gestational diabetes) and long-term adverse health outcomes for the offspring. However, MAFLD during pregnancy is often under-recognized, with limited management/treatment options.

AREAS COVERED

PubMed/MEDLINE, EMBASE, and Scopus were searched based on a search strategy for obesity and/or MAFLD in pregnancy to identify relevant papers up to 2024. This review summarizes the pertinent evidence on the relationship between maternal obesity and MAFLD during pregnancy. Key mechanisms implicated in the underlying pathophysiology linking obesity and MAFLD during pregnancy (e.g. insulin resistance and dysregulated adipokine secretion) are highlighted. Moreover, a diagnostic approach for MAFLD diagnosis during pregnancy and its complications are presented. Finally, promising relevant areas for future research are covered.

EXPERT OPINION

Research progress regarding maternal obesity, MAFLD, and their impact on maternal and fetal/offspring health is expected to improve the relevant diagnostic methods and lead to novel treatments. Thus, routine practice could apply more personalized management strategies, incorporating individualized algorithms with genetic and/or multi-biomarker profiling to guide prevention, early diagnosis, and treatment.

Implications of abnormal liver function in pregnancy and non-alcoholic fatty liver disease

Elevated liver enzyme levels can sometimes be encountered in asymptomatic pregnant women. Similar to non-pregnant subjects, women with elevated gamma glutamyltransferase or alanine aminotransferase in early pregnancy have increased risk of subsequent complications, especially gestational diabetes mellitus. In non-pregnant subjects, the commonest cause of abnormal liver function currently is non-alcoholic fatty liver disease. Risk factors include obesity, diabetes, and the metabolic syndrome. It can progress to hepatocellular carcinoma through the development of steatohepatitis, and has become the leading cause for liver transplantation in women. Found in as many as 16-18% of pregnant women, it is associated with an increased risk of pregnancy complications and abnormal foetal growth, which predisposes the offspring to the same problem subsequently. This condition probably explains the majority of the cases of "idiopathic" abnormal liver function in pregnancy, and should be looked out for in high-risk women owing to its implications on their long-term health outcome.

Baseline Hepatitis B Virus Titer Predicts Initial Postpartum Hepatic Flare: A Multicenter Prospective Study

BACKGROUND AND GOALS

A series of changes in the immune system occur during pregnancy and puerperium. Currently, we aim to characterize both the natural changes in liver inflammation and its association with hepatitis B viremia during this special period.

PATIENTS AND METHODS

Chronic hepatitis B (CHB) gravidas were recruited and followed up to 52 weeks postpartum. Virological and biochemical parameters were assessed throughout the period.

RESULTS

A total of 1097 CHB mothers had finished the entire follow-up including 451 accepting telbivudine, 178 accepting tenofovir, and 468 without antiviral therapy. Among the mothers, 11.94% went through hepatic flare in the first trimester and the rate decreased to 2.1% at the time of delivery. Nevertheless, a much higher frequency (19.78%) was observed in the early postpartum. Interestingly, alanine aminotransferase level decreased along with the development of pregnancy and then suddenly increased in the first month of puerperium. In addition, a downward trend was observed on the titer of HBsAg and HBeAg after delivery. Of note, an obvious higher frequency of alanine aminotransferase flare was revealed in mothers with high viremia (>6 log10 IU/mL). With multivariate analysis, only hepatitis B virus titer at baseline was strongly associated with hepatic flare during early postpartum (95% confidence interval, 1.012-3.049, P=0.045). The predictive rates of hepatic flare at baseline viral load of 6, 7, and 8 log10 IU/mL were 16.67%, 28.30%, and 30.60%, respectively.

CONCLUSIONS

CHB gravidas with high viremia should be monitored closely during entire pregnancy, and extended antiviral therapy is recommend to those mothers with baseline viremia >7 log10 IU/mL.

Mechanisms and Prevention of Vertical Transmission in Chronic Viral Hepatitis

Vertical transmission (VT) is the primary route of transmission of viral hepatitis in children. The rate of VT ranges from 1-28% with hepatitis B virus (HBV) and 3-15% with hepatitis C virus (HCV). VT for both viruses can occur during the intrauterine or peripartum period. VT of HBV primarily occurs by intrauterine transmission (IUT). Hepatitis B surface antigen is unable to cross the placenta and, therefore, relies on processes like transplacental leakage, placental infection, cellular transmission by peripheral blood mononuclear cells, and germline transmission. HCV can also infect the fetus by IUT. Both viruses also have the potential for transmission during delivery, when there is increase chance of maternal-fetal blood exposure. HBV and HCV share some common risk factors for VT, including maternal viral load, human immunodeficiency virus co-infection and neonatal sex. Prevention of VT differs greatly between HBV and HCV. There are several alternatives for prevention of HBV VT, including antiviral medications during the third trimester of pregnancy and HBV vaccine, as well as hepatitis B immunoglobulin administration to infants post-partum. In contrast, there are no preventative interventions available for HCV. Despite these differences, the key to prevention with both viruses is screening women prior to and during pregnancy.

Hepatic flare after telbivudine withdrawal and efficacy of postpartum antiviral therapy for pregnancies with chronic hepatitis B virus

BACKGROUND AND AIM

The efficacy of telbivudine for breaking vertical transmission of hepatitis B virus has been well established. Data on the risk of postpartum flare after telbivudine withdrawal and efficacy of extended antiviral therapy after delivery are limited.

METHODS

Chronic hepatitis B virus-infected women who received telbivudine beginning at week 24 or 28 of gestation were enrolled and then followed up to 52 weeks postpartum. Virological and biochemical parameters were assessed.

RESULTS

Of the 241 women who finished 52 weeks of follow-up, 33.6% had elevated serum alanine aminotransferase (ALT) during pregnancy. Telbivudine administration resulted in ALT normalization in 85.2% before delivery. Compared with women having a normal ALT level throughout pregnancy, those with elevated ALT had a significantly higher rate of ALT flare after telbivudine withdrawal (25.0% vs 11.9%; χ²  = 4.273, P = 0.039). Multivariate analysis indicated that only ALT elevation during pregnancy correlated with postpartum flare after telbivudine withdrawal. Those women with elevated ALT during pregnancy continued antiviral treatment to 52 weeks postpartum and had a significantly higher HBeAg seroconversion rate (P = 0.001) and a notable decrease in HBsAg titers (P = 0.001).

CONCLUSION

It is safe for the majority of women to withdraw telbivudine after delivery, whereas exciting serological response encourages extended antiviral therapy for mother with ALT elevation during pregnancy.