alt lab definition
How is it used? The alanine aminotransferase (ALT) test is typically used to detect liver injury. It is often ordered in conjunction with aspartate aminotransferase (AST) as part of a liver panel or comprehensive metabolic panel (CMP) to screen for and/or help diagnose liver disease. ALT is an enzyme found mostly in the cells of the liver and kidney. When the liver is damaged, ALT is released into the blood. This makes ALT a useful test for early detection of liver damage. AST and ALT are considered to be two of the most important tests to detect liver injury, although ALT is more specific to the liver than is AST.