Hepatitis B virus (HBV) is the most common cause of liver disease, cirrhosis and liver cancer in the world. HBV is very common in China, Southeast Asia, many countries within Africa, South America and Eastern Europe. In the USA immigrants from these parts of the world account for over half of all persons with chronic HBV. The most common way in which persons become infected with HBV is through vertical transmission, at the time of birth by a mother with chronic HBV. This is why all pregnant women in the USA are tested for HBV. If the mother has chronic HBV the baby can be vaccinated at birth and this is highly effective in preventing transmission. HBV can also be acquired through sexual contact and by utilizing intravenous drugs with a person who already has HBV.
HBV can resolve spontaneously after a person is exposed to this virus. Spontaneous resolution occurs in over 90% of persons who are infected with HBV as adults. In contrast, spontaneous resolution is rare if infants acquire HBV vertically at birth. Persons who do not spontaneously resolve HBV develop chronic infection. This means HBV does not go away. Many, but not all patients with chronic HBV have elevated liver enzymes in their blood. Blood tests can detect these elevated liver enzymes and the amount of virus (HBV DNA) in the blood of an infected patient. The level of HV DNA in the blood of a person with chronic HBV is directly related to the severity of the liver disease and risk of developing liver cancer. Patients with very high levels of HBV DNA have the greatest risk of developing both cirrhosis and liver cancer.
The majority of patients with chronic HBV are asymptomatic. Of those patients with symptoms, the most common is fatigue.
Chronic HBV exists in one of several states. Patients with active HBV have elevated liver enzymes and high levels of HBV in the blood. These patients are at risk of developing cirrhosis and liver cancer. Treatment of HBV is therefore indicated in patients with active HBV. Other patients have inactive HBV. These patients typically have normal liver enzymes and low levels or undetectable amounts of HBV in the blood. These patients are at very low risk of developing liver cancer. These patients should be monitored. Treatment as not been shown to be effective in these patients.
Several highly effective anti-viral agents are available for the treatment of chronic HBV. The two most effective medications, entecovir and tenofovir, are pills taken orally once daily. Both reduce the level of HBV in the blood by inhibiting the ability of HBV to reproduce and this converts active HBV into inactive HBV. Although some patients may be able to stop treatment with thee ral anti-viral agents after several years, the vast majority of patients with chronic HBV must be treated lifelong.
Peginterferon is also highly effective against certain types of active HBV. Peginterferon is administered once weekly by subcutaneous (under the skin) injection for either 6-12 months. Peginterferon acts by stimulating the immune system to attack and eradicate (kill) HBV. This converts active to inactive HBV. The main disadvantage of peginterferon are side effects. Peginterferon causes flu-like symptoms such as aches and pains in the muscles and joints, fevers, chills and headache. These side-effects are worst after the first injection but gradually get better and may go away in many patients after 2-4 weeks. If the flu-like symptoms persist over many weeks-months patients may develop irritability, difficulty sleeping and depression.
Dr. Shiffman, of the Liver Institute of Virginia, lectures in the USA and worldwide and has written many articles to help other physicians understand how to better manage and treat patients with chronic HBV. Dr Shiffman also has conducted numerous studies aimed at improving the treatment of chronic HBV.
Treatment for chronic HBV is available at the Liver Institute of Virginia. A complete evaluation by Dr Shiffman or April Long, NP will be performed to determine if treatment is necessary and what medication would be the best for each patient with chronic HBV if treatment is required.
Clinical trials utilizing many new medications for treating chronic HCV are being conducted by the Liver Institute of Virginia. Patients may be eligible for enrollment into a clinical trial after a complete evaluation. These clinical trials may offer patients a higher cure rate, be associated with less side effects during the treatment or both.