Description
AST is found in red blood cells, liver, heart, muscle tissue, pancreas, and kidneys. Formerly it was called serum glutamic oxaloacetic transaminase (SGOT).
Low levels of AST are normally found in the blood. When body tissue or an organ such as the heart or liver is diseased or damaged, additional AST is released into the bloodstream. The amount of AST in the blood is directly related to the extent of the tissue damage.
Its concentration is measured by means of analysis of a blood sample drawn from the vein in the arm.
Purpose of the test
This test is normally done to:
- Check for liver damage.
- Check for liver disease, especially hepatitis and cirrhosis.
- Check on the success of treatment for liver disease.
- Keep track of the effect of medicines that can damage the liver.
Reference range values
8-35 U/L
Abnormal findings
High levels of AST may be caused by:
- Recent or severe liver damage, such as hepatitis caused by a viral infection or drug reaction.
- Decay of a large tumor (necrosis).
- Shock.
Moderately high levels may be caused by:
- Chronic diseases affecting the liver, such as cirrhosis.
- Heart attack or heart failure.
- Alcohol abuse.
- High doses of vitamin A.
- Kidney or lung damage.
- Mononucleosis.
- Duchenne muscular dystrophy.
- Some types of cancer.
- Myositis.
Slightly high levels of AST may be caused by:
- Fatty deposits in the liver.
- Medicines, such as statins, antibiotics, chemotherapy, aspirin, narcotics, and barbiturates.
- Alcohol abuse.
AST levels are high when a disease first develops, which is often when tissue damage is most severe. Decreasing levels of AST in the blood may be a sign of recovery from the disease or injury.
Other conditions, including severe burns, traumatic injuries, pulmonary embolism, or heat exhaustion and heatstroke, and ingestion of poisonous mushrooms may cause elevated AST levels.