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Chronic hepatitis
is inflammation of the liver that lasts at least 6 months.
Chronic hepatitis, although much less common than acute hepatitis, can persist for years, even decades. In most people, it is quite mild and does not cause significant liver damage. However, in some people, continued inflammation slowly damages the liver, eventually resulting in cirrhosis (severe scarring of the liver), liver failure, and sometimes liver cancer.
Causes
Chronic hepatitis is usually caused by one of the hepatitis viruses (see Hepatitis:Introduction ). Hepatitis C virus causes about 60 to 70% of cases, and at least 75% of acute hepatitis C cases become chronic. About 5 to 7% of hepatitis B cases, sometimes with hepatitis D co-infection, become chronic. Hepatitis A and E viruses do not cause chronic hepatitis.
Certain drugs can cause chronic hepatitis, particularly when they are taken for a long time. They include isoniazid, methyldopa, nitrofurantoin, and, rarely, acetaminophen. Wilson's disease, a rare hereditary disorder involving abnormal retention of copper in the liver (see Causes of Hyponatremia ), may cause chronic hepatitis in children and young adults. Other causes include alcoholic hepatitis, fatty liver not due to alcohol use (nonalcoholic steatohepatitis), and alpha1-antitrypsin deficiency (a hereditary disorder).
No one knows exactly why a particular virus or drug causes chronic hepatitis in some people but not in others or why the degree of severity varies. In many people with chronic hepatitis, no obvious cause can be found. In some of these people, the chronic inflammation resembles inflammation caused by the body attacking its own tissues (an autoimmune reaction (see Autoimmune Disorders), but this connection has not been proven. This type of inflammation called autoimmune hepatitis, is more common among women than men.
Symptoms
In about two thirds of people, chronic hepatitis develops gradually without causing any obvious symptoms until cirrhosis occurs. In the remaining one third, it develops after a bout of acute viral hepatitis that persists or returns (often several weeks later).
Symptoms often include a vague feeling of illness (malaise), poor appetite, and fatigue. Sometimes affected people also have a low-grade fever and some upper abdominal discomfort. Jaundice is rare. Complications of chronic liver disease and cirrhosis may eventually develop. They can include an enlarged spleen, spiderlike blood vessels in the skin, redness of the palms, and accumulation of fluid in the abdominal cavity (ascites—see Manifestations of Liver Disease: Ascites). Liver malfunction may lead to deterioration of brain function (hepatic encephalopathy), particularly in people with cirrhosis due to hepatitis C (see Manifestations of Liver Disease: Hepatic Encephalopathy).
Autoimmune hepatitis may cause other symptoms that can involve virtually any body system, especially in young women. Such symptoms include acne, cessation of menstrual periods, joint pain, lung scarring, inflammation of the thyroid gland and kidneys, and anemia.
In many people, chronic hepatitis does not progress for years. In others, it gradually worsens. The outlook depends partly on which virus is the cause:
Diagnosis
Doctors may suspect hepatitis C when people have typical symptoms, when blood tests to evaluate liver function are abnormal, or when people have had hepatitis C before. Blood tests are done and may help establish the diagnosis, identify the cause, and determine the severity of liver damage. However, a liver biopsy (see Diagnostic Tests for Liver, Gallbladder, and Biliary Disorders: Biopsy of the Liver) is essential for a definite diagnosis. The liver biopsy also enables a doctor to determine how severe the inflammation is and whether any scarring or cirrhosis has developed. The biopsy may help identify the cause of hepatitis. Occasionally, a biopsy needs to be done more than once.
If people have chronic hepatitis B, ultrasonography and blood tests to measure alpha–fetoprotein levels are done annually to screen for liver cancer. Levels of alpha–fetoprotein—a protein normally produced by immature liver cells in fetuses—usually increase when liver cancer is present. People with chronic hepatitis C are screened similarly, but only if they have cirrhosis.
Treatment
If a drug is the cause, the drug is stopped. If another disorder is the cause, it is treated.
Hepatitis
B and C:
People with progressive chronic hepatitis B or C are usually given antiviral drugs. For hepatitis B, entecavir, adefovir, or lamivudine is usually used. These drugs are taken by mouth, as is telbivudine, a new drug for which little information is available. Interferon-alpha or pegylated interferon-alpha, given by injection under the skin, may be used instead of an oral drug. Hepatitis B tends to recur once drug treatment is stopped and may be even more severe. Thus, an antiviral drug may need to be taken indefinitely.
For hepatitis C, pegylated interferon-alpha plus ribavirin is most effective. This combination may stop the inflammation. After taking these drugs for 6 months to 1 year, 45 to 75% of people improve and have no further problems.
Antiviral drugs used to treat chronic hepatitis commonly cause side effects. Lamivudine may have fewer side effects than the others. These drugs should not be taken by people who have certain conditions:
If family members and close contacts of people with chronic hepatitis B have not been vaccinated, they should be. They are also given hepatitis B immune globulin. Such measures are not necessary for chronic hepatitis C.
Autoimmune Hepatitis:
Usually, corticosteroids (such as prednisone) are used, sometimes with azathioprine, a drug used to suppress the immune system. These drugs suppress the inflammation, relieve symptoms, and improve long-term survival. Nevertheless, scarring in the liver may gradually worsen. Stopping these drugs usually leads to recurrence of the inflammation, so most people have to take the drugs indefinitely.
Complications:
Regardless of the cause or type of chronic hepatitis, complications require treatment. For example, treating ascites involves restriction of salt consumption, bed rest, and sometimes drugs. If brain function deteriorates, eliminating protein from the diet can help.
Liver Transplantation:
Transplantation (see Transplantation: Liver Transplantation) may be considered for people with severe liver failure. However, in people who have hepatitis B or hepatitis C, the virus tends to infect the transplanted liver. In people with hepatitis B, the virus tends to severely damage the transplanted liver over months or a few years, but taking lamivudine may improve the outcome. In people with hepatitis C, the virus virtually always recurs in the transplanted liver, but the infection is usually so mild that people are likely to survive for many years.
Last full review/revision May 2007 by Sidney Cohen, MD
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