The liver is one of the most functionally diverse of the body organs. Its many activities include regulation of sugar and fat metabolism, deactivation of medications, detoxification of damaging chemicals, protein production and storage of essential body nutrients and minerals. Infections, toxins, storage disorders and chronic inflammatory conditions can lead to chronic liver disease, which may progress to cirrhosis. Prompt diagnosis and treatment of chronic liver disease can delay or prevent progression to cirrhosis.
Chronic Viral Hepatitis
Chronic viral hepatitis, due to the hepatitis B or hepatitis C virus, is a leading cause of chronic liver disease in the United States. Ongoing infection prompts a chronic inflammatory response by the immune system, which often damages the liver. Scar tissue may form in the liver due to chronic inflammation, a condition termed fibrosis. Severe fibrosis that distorts the internal structure of the liver defines cirrhosis. The function of a cirrhotic liver may decline to the point of liver failure in which the liver is unable to perform vital functions. Chronic hepatitis B and C also increase the risk for liver cancer. The Centers for Disease Control and Prevention (CDC) reports that an estimated 3.2 million people in the United States are chronically infected with the hepatitis C virus. An additional 1.2 million have chronic hepatitis B. Chronic viral hepatitis is the leading indication for liver transplantation and the most common cause of liver cancer in the United States.
Alcoholic Hepatitis and Cirrhosis
Protracted, excessive alcohol intake provokes fat accumulation in liver cells, which may lead to alcoholic hepatitis. As the primary site of alcohol breakdown, the liver develops chemical and metabolic imbalances with ongoing, high levels of alcohol exposure. Fat accumulation within liver cells typically triggers an inflammatory response that may cause damage and scarring. The Cleveland Clinic reports that liver damage associated with alcoholic hepatitis may be reversible with abstinence from alcohol. Continued alcohol consumption with an accumulation of scar tissue can progress to cirrhosis and liver failure. The risk of alcoholic cirrhosis increases with the amount and duration of alcohol consumption.
Primary Biliary Cirrhosis
The liver produces bile, a substance that aids in the digestion and absorption of fats in the intestines. A network of bile transport vessels, the intrahepatic bile ducts, collects bile and delivers it to the gallbladder for storage. Primary biliary cirrhosis is a condition wherein the intrahepatic bile ducts progressively deteriorate, leading to a backup of bile in the liver. The bile backup causes liver damage and scarring, with the eventual development of cirrhosis. The American Association for the Study of Liver Diseases reports that treatment with ursodeoxycholic acid significantly slows disease progression with primary biliary cirrhosis.
Hemochromatosis
Excessive iron absorption and storage defines the condition hemochromatosis. Inherited forms of the condition include neonatal, juvenile and hereditary hemochromatosis. Alcoholism, anemia and other diseases may also cause iron overload. As the primary site of iron storage, the liver may sustain damage due to iron overload. The National Institute of Diabetes and Digestive and Kidney Diseases explains that hemochromatosis-induced liver damage can progress to cirrhosis and liver failure.
References
- Centers for Disease Control and Prevention: Viral Hepatitis
- Centers for Disease Control and Prevention: The ABCs of Hepatitis
- Cleveland Clinic Center for Continuing Education: Alcoholic Liver Disease
- University of Maryland Medical Center: Cirrhosis
- National Institute of Diabetes and Digestive and Kidney Diseases: Primary Biliary Cirrhosis
