Chronic Hepatitis B in Children - A Review.

Hepatitis B Virus (HBV) infection is prevalent worldwide. The prevalence is lowest (0.2-0.5%) in countries having high standard of living. About 10 million people are chronically infected with HBV in Bangladesh and it is possible that most infections occur during childhood. Overall prevalence is about 3% in Bangladesh. Perinatal transmission is more common in hyper-endemic areas of South East Asia. Chronic hepatitis B infection evolves through five phases. Most of the children belong to immune tolerant phase. About 57% patients of chronic hepatitis B are asymptomatic. Treatment of chronic hepatitis B is difficult. Decision regarding when, whom and how to treat in children is complex. Moreover, there are only limited drugs that can be used in treating chronic hepatitis B in children. Goal of therapy are to reduce viral replication, to minimize liver injury, to reduce consequence of liver injury like cirrhosis, hepatocellular carcinoma and to reduce infectivity of HBV. Treatment should be considered in chronic hepatitis B if patient have persistently elevated ALT of more than twice normal and evidence of viral replication. There are some special circumstances where treatment of chronic hepatitis B can be given in absence of standard criteria. These conditions are cirrhosis, chemotherapy, immunosuppression, presence of co-infection (HBV-HIV), family history of HCC and pregnant women with high viral load. Sero-conversion occurs in about 17-32% cases if treated with oral nucleot(s)ide analogue and in about 58% cases if treated with interferon. These expensive drugs with limited treatment success are not suitable for the people of Bangladesh. Therefore, risk factors identification and prevention of HBV infection is the logical and rational approach for a country like Bangladesh. Vaccination against HBV play central role in preventing infection. HBV vaccine has been incorporated in EPI schedule since 2004 in Bangladesh. Immunoprophylaxis of babies of HBsAg positive mother and post exposure prophylaxis are effective ways of prevention.