Hepatitis B is a common cause of chronic hepatitis. Patients may be asymptomatic or have nonspecific manifestations such as fatigue and malaise. Without treatment, cirrhosis often develops; risk of hepatocellular carcinoma is increased. Antiviral drugs may help, but liver transplantation may become necessary.
(See also Causes of Hepatitis, Overview of Chronic Hepatitis, and Acute Hepatitis B.)
Hepatitis lasting gt; 6 months is generally defined as chronic hepatitis, although this duration is arbitrary.
Acute hepatitis B becomes chronic in about 5 to 10% of patients overall. However, the younger the age when acute infection occurs, the higher the risk of developing chronic infection:
For infants: 90%
For children aged 1 to 5 years: 25 to 50%
For adults: About 5%
The Centers for Disease Control and Prevention (CDC) estimates that 850,000 to 2.2 million people in the US (1) and about 257 million people worldwide have chronic hepatitis B (2).
Without treatment, chronic hepatitis B can resolve (uncommon), progress rapidly, or progress slowly to cirrhosis over decades. Resolution often begins with a transient increase in disease severity and results in seroconversion from hepatitis B e antigen (HBeAg) to antibody to hepatitis B e antigen (anti-HBe). Coinfection with hepatitis D virus (HDV) causes the most severe form of chronic HBV infection; without treatment, cirrhosis develops in up to 70% of patients. Chronic HBV infection increases the risk of hepatocellular carcinoma.