AST in a blood test stands for aspartate aminotransferase , an enzyme found mainly in the liver but also in the heart, muscles, kidneys, brain, and other tissues. It plays a role in chemical reactions that help convert amino acids into energy
. Normally, only low levels of AST are present in the blood. When cells in the liver or other organs that contain AST are damaged, AST is released into the bloodstream, causing elevated levels. Therefore, an AST blood test is primarily used to help diagnose or monitor liver damage or disease. It can also indicate damage to other organs like the heart or muscles
. The AST test is often ordered as part of liver function tests, sometimes alongside alanine aminotransferase (ALT), another liver enzyme. High AST levels may suggest liver inflammation, injury, or diseases such as hepatitis, cirrhosis, or liver cancer. Elevated AST can also result from heart attack, muscle injury, or other conditions affecting AST-rich tissues
. Typical normal AST levels for adults are roughly 8 to 33 units per liter (U/L), though ranges can vary slightly by lab. Levels above this range may indicate liver or other tissue damage and warrant further medical evaluation
. In summary, the AST blood test measures the amount of the enzyme aspartate aminotransferase in your blood to assess liver health and detect possible damage to the liver or other organs containing AST
