Hepatitis

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Hepatitis, inflammation of the liver caused by viruses, bacterial infections, or continuous exposure to alcohol, drugs, or toxic chemicals, such as those found in aerosol sprays and paint thinners. Hepatitis can also result from an autoimmune disorder, in which the body mistakenly sends disease-fighting cells to attack its own healthy tissue, in this case the liver. No matter what its cause, hepatitis reduces the liver’s ability to perform life-preserving functions, including filtering harmful infectious agents from the blood, storing blood sugar and converting it to usable energy forms, and producing many proteins necessary for life.

Symptoms of hepatitis vary significantly depending on the cause and the overall health of the infected individual. Some cases of hepatitis have few, if any, noticeable symptoms. When symptoms are present, they may include general weakness and fatigue, loss of appetite, nausea, fever, and abdominal pain and tenderness. Another symptom is jaundice, a yellowing of the skin and eyes that occurs when the liver fails to break down excess yellow-colored bile pigments in the blood.

In acute hepatitis, symptoms often subside without treatment within a few weeks or months. About 5 percent of cases develop into an incurable form of the disease called chronic hepatitis, which may last for years. Chronic hepatitis causes slowly progressive liver damage that may lead to cirrhosis, a condition in which healthy liver tissue is replaced with dead, nonfunctional scar tissue. In some cases, cancer of the liver develops.

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