From the Guidelines
Chronic hepatitis B is defined as a persistent hepatitis B virus (HBV) infection lasting more than six months, characterized by the presence of hepatitis B surface antigen (HBsAg) in the blood for at least that duration, and can be classified into five phases: (I) HBeAg-positive chronic infection, (II) HBeAg-positive chronic hepatitis, (III) HBeAg-negative chronic infection, (IV) HBeAg-negative chronic hepatitis and (V) HBsAg-negative phase, as outlined in the EASL 2017 clinical practice guidelines 1. The diagnosis of chronic hepatitis B requires laboratory confirmation through blood tests showing persistent HBsAg positivity, along with other markers such as hepatitis B e-antigen (HBeAg), HBV DNA levels, and liver function tests. Key characteristics of chronic hepatitis B include:
- Persistent HBV infection lasting more than six months
- Presence of HBsAg in the blood for at least six months
- Potential progression to cirrhosis and hepatocellular carcinoma (HCC)
- Classification into five phases, as mentioned earlier Many patients with chronic hepatitis B are asymptomatic, especially in the early stages, though some may experience fatigue, abdominal pain, jaundice, or signs of advanced liver disease. The condition results from an inadequate immune response that fails to clear the virus after initial infection, allowing it to establish a permanent presence in liver cells, as discussed in the EASL clinical practice guidelines 1. Regular monitoring is essential for all patients with chronic hepatitis B, even those without symptoms, as the disease can silently progress and cause serious liver damage over decades, highlighting the importance of long-term follow-up and management, as recommended in the EASL 2017 guidelines 1.
From the Research
Definition of Chronic Hepatitis B
- Chronic hepatitis B is defined as the persistence of hepatitis B surface antigen for more than six months 2
- It is a condition where the hepatitis B virus (HBV) infection persists in the liver, leading to liver inflammation, fibrosis, and potentially liver cancer 3, 4
- The natural course of the disease is highly dynamic, and not every patient requires therapy, making constant monitoring mandatory to predict the natural course and guide treatment decisions 3
Key Characteristics
- Chronic hepatitis B infection can result in liver cirrhosis, hepatic decompensation, and hepatocellular carcinoma (HCC) 3, 4
- The risk of liver cancer is positively related to increasing levels of HBV-DNA and HBsAg in dose-response manners 5
- Elevated levels of HBV-DNA and HBsAg are associated with increased risks of liver cancer, and chronic HBsAg carriers may be suggested to simultaneously lower the viral load to < 2000 IU/ml and HBsAg level to < 100 IU/ml to lower their liver cancer risk 5
Diagnosis and Treatment
- Screening for hepatitis B is recommended in pregnant women, adolescents, and adults at high risk of chronic infection 2
- Treatment should be individualized based on clinical and laboratory characteristics and the risks of developing cirrhosis and hepatocellular carcinoma 2
- Antiviral treatment with either pegylated interferon or a nucleos(t)ide analogue should be offered to patients with chronic HBV infection and liver inflammation to reduce progression of liver disease 4