Hepatitis B, Chronic
Most people with chronic hepatitis B have no symptoms, but some feel generally ill and tired and lose their appetite.
Having chronic hepatitis B increases the risk of liver cancer.
Doctors diagnose hepatitis B based on blood tests and occasionally do a liver biopsy to determine how damaged the liver is.
Not all patients with chronic hepatitis B need treatment, but if chronic hepatitis B is damaging the liver (causing inflammation or scarring), an antiviral drug is started.
Treatment with antiviral drugs can help suppress the virus, prevent further inflammation and scarring in the liver, and allow any already damaged areas to heal.
An estimated 850,000 to 2.2 million people in the United States and about 257 million people worldwide have chronic hepatitis B.
Overall, about 5% to 10% of people with acute hepatitis B develop chronic hepatitis B. The younger the person is when acute hepatitis B occurs, the higher the risk of developing chronic hepatitis B:
If the level of hepatitis B virus (viral load) is high in pregnant women, they are often given antiviral drugs during the last trimester of pregnancy to prevent transmission of the virus from mother to child.
Acute hepatitis B becomes chronic in about 40% of people being treated with hemodialysis and in up to 20% of people with a weakened immune system.
Chronic hepatitis B tends to worsen, sometimes rapidly but sometimes over decades, leading to cirrhosis. Chronic hepatitis B also increases the risk of liver cancer. About 20% of people with chronic hepatitis B develop cirrhosis or liver cancer and may die prematurely.
Some people who have chronic hepatitis B also have chronic hepatitis D. If untreated, the combination causes cirrhosis in up to 70% of affected people.
Symptoms of chronic hepatitis B vary depending on how badly the liver is damaged.
Many people with chronic hepatitis B, particularly children, have no symptoms. People who have symptoms usually feel generally ill and tired and lose their appetite. Some people have a low-grade fever and vague discomfort in the upper abdomen. Some people with chronic hepatitis B have jaundice (yellowing of the skin and whites of the eyes).
Often, the first specific symptoms occur when the liver disease has progressed and there is evidence of cirrhosis. Symptoms can include
An enlarged spleen
Small spiderlike blood vessels visible in the skin (called spider angiomas)
Redness of the palms
Accumulation of fluid within the abdomen (ascites)
A tendency to bleed (coagulopathy)
Jaundice (yellowing of the skin and whites of the eyes)
Deterioration of brain function due to malfunction of the liver (hepatic encephalopathy)
Brain function deteriorates because toxic substances build up in the blood and reach the brain. The liver normally removes them from the blood, breaks them down, then excretes them as harmless by-products into the bile or blood. The badly damaged liver is less able to remove them.
People have a tendency to bleed because the damaged liver can no longer synthesize enough of the proteins that help blood clot.
Jaundice and itchiness develop because the damaged liver cannot remove bilirubin from the blood as it normally does. Bilirubin then builds up in the blood and is deposited in the skin. (Bilirubin is a yellow pigment produced as a waste product during the normal breakdown of red blood cells.) Stool is light-colored because the flow of bile out of the liver is blocked, so that less bilirubin is eliminated in stool. Bilirubin is what gives stool its typical brown color.
Doctors may suspect chronic hepatitis B when
Testing for chronic hepatitis usually begins with blood tests to determine how well the liver is functioning and whether it is damaged (liver tests). Liver tests involve measuring the levels of liver enzymes and other substances produced by the liver. These tests may help determine the severity of liver damage.
If tests suggest hepatitis, doctors do other blood tests to check for the hepatitis B and C viruses. Both can cause chronic hepatitis. These blood tests can identify parts of specific viruses (antigens), specific antibodies produced by the body to fight the virus, and sometimes genetic material (RNA or DNA) of the virus. If doctors strongly suspect only hepatitis B, they may do blood tests for only that virus.
Doctors do blood tests to measure viral load, which is the amount of the hepatitis B virus's genetic material (DNA) that is present.
If chronic hepatitis B is confirmed, doctors also check for antibodies to hepatitis D, which can also be present, and for HIV infection and hepatitis C because these infections are often spread in the same ways (through contact with bodily fluids, such as blood or semen).
A liver biopsy may be done to determine how badly the liver is damaged.
If people have chronic hepatitis B, screening for liver cancer is done every 6 months. The following are done:
Levels of alpha-fetoprotein—a protein normally produced by immature liver cells in fetuses—usually increase when liver cancer is present.
Antiviral drugs are used when people have one or a combination of the following:
Treatment of hepatitis B with antiviral drugs can prevent further damage to the liver and allow any already damaged areas to heal. Most people treated for chronic hepatitis B must be treated indefinitely.
Stopping treatment prematurely can lead to relapse, which may be severe. However, treatment may be stopped if blood tests no longer detect any active hepatitis B virus infection.
One of the following antiviral drugs is usually used first:
These drugs are taken by mouth, are very effective, and have few side effects.
Other drugs that are sometimes used include adefovir, lamivudine, and telbivudine. However, these drugs are no longer used first because they have an increased risk of side effects and can lose their effectiveness (called drug resistance).
Liver transplantation should be considered if liver function is severely impaired. The transplanted liver is more likely to survive and hepatitis B is less likely to recur if
Hepatitis B immune globulin is obtained from the blood of people who have high levels of antibodies to hepatitis B. It is given by injection into a muscle or into a vein. It helps the body fight infection.