Located in the right upper part of the abdomen, under the rib cage, the liver uses proteins to help the body eliminate toxins and metabolize medications and other substances. Liver enzymes are proteins inside liver cells that leak out into the bloodstream when there is liver damage, inflammation or infection. Blood tests can then measure the level of liver enzyme elevation and track the progress of liver damage and recovery. One of the most common causes of elevated liver enzymes is viral infection.
Liver Enzymes
The two most frequently monitored liver enzymes are AST, or aspartate aminotransferase, and ALT, or alanine aminotransferase. According to Lab Tests Online, ALT is more specific to the liver, since this enzyme is located mostly within that organ. In comparison, AST is found in other tissues, like the heart and muscles, so elevations of AST are not specific to liver damage. When liver enzymes become elevated, the person is said to have hepatitis.
Viral Hepatitis
Several viruses can cause hepatitis. These include hepatitis A, B and C; Epstein-Barr virus, which causes mononucleosis; and cytomegalovirus. According to the University of Maryland Medical Center, type A is the most common form of viral hepatitis. Risk factors for transmission include ingestion of food or water contaminated with fecal matter. The hepatitis B and C viruses can cause an acute short-term illness or progress to a chronic hepatitis state. Risk factors for acquiring hepatitis B and C include blood transfusions, intravenous drug use and unprotected sex with an infected partner.
Symptoms
The symptoms of hepatitis start as a flu-like illness with fever and muscle and joint aches. Eventually, the person develops abdominal pain, particularly in the area where the liver is localized; nausea and vomiting, which can lead to dehydration; weight loss and fatigue. As the disease progresses, the skin and the whites of the eyes acquire a yellowish tinge, known as jaundice, which can also cause itchiness and discomfort. The urine can turn dark and the stools acquire a pale appearance. In the acute phase, the liver becomes tender and enlarged, but in the chronic state the person may develop cirrhosis and have shrinking and scarring of the liver tissue.
Treatment
Most cases of viral hepatitis are short-lived, and the person only requires supportive treatment with intravenous fluids to prevent dehydration, and fever and pain control. The person may require intravenous nutrition to maintain the body's energy needs. In rare cases, a liver transplantation may be necessary if the person is to survive the infection.
