Aspartate Aminotransferase (AST/SGOT)

The Aspartate Aminotransferase (AST/SGOT) test is used to identify and assess hepatocellular injury and to monitor disease activity and treatment response in liver disorders. Results are interpreted with ALT, alkaline phosphatase, bilirubin, and related tests to differentiate hepatocellular from cholestatic patterns; the AST to ALT ratio can aid evaluation of alcohol-associated liver disease. AST (aspartate transaminase; Serum Glutamic Oxaloacetic Transaminase) may also rise with cardiac or skeletal muscle injury, including myocardial infarction, myositis, and muscular dystrophies, as well as during systemic inflammatory or ischemic states. Accordingly, interpretation relies on clinical context and, when appropriate, complementary cardiac and muscle biomarkers.

AST is distributed widely across tissues, with highest activity in liver and heart and comparatively lower activity in kidney and skeletal muscle. Serum AST increases with hepatocellular injury and with muscle injury, so it is commonly included in liver test panels but is not liver-specific. Clinical interpretation requires integration with ALT, alkaline phosphatase, bilirubin, and the physical examination, and, when indicated, with cardiac and muscle biomarkers. Marked elevations are typical of acute hepatocellular injury, whereas extrahepatic processes such as myocardial infarction and myopathies can also produce elevated AST.