Hepatitis B virus (HBV) remains a major global health problem. HBV DNA can be integrated into the human chromosomes. The integration in young cirrhotic chronic hepatitis B children has not been explored. This study aims to investigate HBV DNA integration in early childhood cirrhosis.

Biopsy liver specimens from cirrhotic and matched non-cirrhotic chronic hepatitis B children were collected. HBV DNA integration was detected through targeted HBV DNA fragment capture sequencing.

Twenty cirrhotic and 20 non-cirrhotic children with chronic hepatitis B were included in the study. The cirrhotic group included 14 males and 6 females, and the non-cirrhotic group included 13 males and 7 females. Compared to non-cirrhotic children, cirrhotic children had lower serum HBsAg quantification (p = 0.001). The median number of HBV integrants in the cirrhotic group was 59 and that in the non-cirrhotic group was 98. No significant difference existed between the two groups (p = 0.529). In the multivariate linear regression analysis, serum HBV DNA level was correlated with the number of HBV integrants (p < 0.001, R2 = 0.322). Six differential intragenic high-frequency viral integration sites in cirrhotic children were revealed, all of which have protein-coding functions.

Several frequently integrated genes were observed in early childhood cirrhosis. Detailed associations between genetic alterations induced by HBV integration and early childhood cirrhosis need further exploration.

Cirrhosis causes a heavy global burden. In this review, we summarized up-to-date epidemiological features of cirrhosis and its complications. Recent epidemiological studies reported an increase in the prevalence of cirrhosis in 2017 compared to in 1990 in both men and women, with 5.2 million cases of cirrhosis and chronic liver disease occurring in 2017. Cirrhosis caused 1.48 million deaths in 2019, an increase of 8.1% compared to 2017. Disability-adjusted life-years due to cirrhosis ranked 16th among all diseases and 7th in people aged 50-74 years in 2019. The global burden of hepatitis B virus and hepatitis C virus-associated cirrhosis is decreasing, while the burden of cirrhosis due to alcohol and nonalcoholic fatty liver disease (NAFLD) is increasing rapidly. We described the current epidemiology of the major complications of cirrhosis, including ascites, variceal bleeding, hepatic encephalopathy, renal disorders, and infections. We also summarized the epidemiology of hepatocellular carcinoma in patients with cirrhosis. In the future, NAFLD-related cirrhosis will likely become more common due to the prevalence of metabolic diseases such as obesity and diabetes, and the prevalence of alcohol-induced cirrhosis is increasing. This altered epidemiology should be clinically noted, and relevant interventions should be undertaken.