Alanine Aminotransferase (ALT) and Aspartate Aminotransferase (AST)

For a brief introduction and guide to abbreviations, see Laboratory Tests: General Remarks.

Analyte [material]

Alanine aminotransferase (ALT) and aspartate aminotransferase (AST) [S/P]

Reference range, target level, or decision threshold

<40 IU/L

There are age- and sex-specific reference intervals for ALT and AST.CW

Interpretation of results

↑ ≤15 ×, AST/ALT <1: Chronic viral hepatitis type B or C, acute viral hepatitis A-E, acute EBV or CMV hepatitis, hepatic steatosis and steatohepatitis (fatty liver disease), hereditary hemochromatosis, drug-induced or toxic liver injury, autoimmune hepatitis, alpha1-antitrypsin deficiency, Wilson disease, celiac disease

↑≤15 ×, AST/ALT >1: Alcoholic liver disease, hepatic steatosis and steatohepatitis (fatty liver disease), liver cirrhosis, hemolysis, myopathies, MI, thyroid diseases, exercise, macro-AST (clinically insignificant)

>15 ×: Acute viral hepatitis A-E, HSV hepatitis, drug-induced or toxic liver injury, acute hepatic ischemia (hepatic artery occlusion, shock), autoimmune hepatitis, Wilson disease, hepatic vein thrombosis (Budd-Chiari syndrome)