Screening for Cirrhosis - Blood Tests to Diagnose Cirrhosis
What is Cirrhosis?
Cirrhosis is the development of scar tissue in the liver as it heals from cellular damage caused by various agents, including alcohol, medications, viruses, toxic metals, and even the body’s own immune system. Cirrhosis usually occurs at the late stages of liver diseases. There isn’t a specific blood test which can identify the presence of cirrhosis. However, there are several molecules in the blood that can be measured to evaluate how well the liver is functioning.
Usually, these blood tests are ordered when certain symptoms arise. Some of the symptoms associated with cirrhosis include yellowing of the skin, fatigue, weakness, and loss of appetite. These symptoms may not show until the disease has significantly progressed.
ALT
One of the blood tests to diagnose cirrhosis is the ALT blood test, which measures the amount of alanine aminotransferase in the blood. Alanine aminotransferase is an enzyme that is present in the liver. When the liver is damaged, it releases alanine aminotransferase into the blood. Normally, the level of alanine aminotransferase is low. If the blood test reveals an elevated level, it may indicate several liver diseases. Cirrhosis may be present, but the elevated level can also indicate chronic hepatitis or bile duct obstruction.
AST
Another test to evaluate liver function and aid in the diagnosis of cirrhosis is the AST blood test. It measures the amount of aspartate aminotransferase in the blood. Aspartate aminotransferase is released from the liver when it is injured. Like the ALT test, the AST blood test can indicate several problems with the liver. Elevated levels can indicate liver damage from drugs, viral infection, or cancer. Scar tissue associated with cirrhosis and obstruction of bile ducts is also probable.
Albumin
The level of albumin in the blood can also indicate the presence of cirrhosis. Albumin is a protein that transports molecules through the blood. It is produced in the liver, and is the most abundant protein in the blood. A decrease in the amount of albumin in the blood indicates that the liver is severely damaged. Usually, albumin levels drop when the liver’s ability to produce albumin diminishes.
Auto-Antibodies
Blood tests to diagnose cirrhosis include tests that measure auto-antibodies. Auto-antibodies are proteins that are produced by the immune system and target the body. A common auto-antibody test is the antinuclear antibody test. It can detect auto-antibodies that attack the liver and cause autoimmune hepatitis and primary biliary cirrhosis.
Reference
1. “Cirrhosis.” Medicine Net. Web 9 Dec. 2010
2. “AST.” Lab Tests Online. American Association for Clinical Chemistry. 24 Nov. 2010. Web 9 Dec 2010.
3. “ALT.” Lab Tests Online. American Association for Clinical Chemistry. 24 Nov. 2010. Web 9 Dec 2010.
4. “Autoantibodies.” Lab Tests Online. American Association for Clinical Chemistry. 24 Nov. 2010. Web 9 Dec. 2010.
5. “Albumin.” RnCeus Interactive. Web 9 Dec. 2010.
