Aspartate aminotransferase (AST) and alanine aminotransferase (ALT) are measured by the serum glutamic-oxaloacetic transaminase (SGOT) and serum glutamic-pyruvic transaminase (SGPT) respectively. They are important markers of hepatocellular injury. Normal values: (varies from lab to lab but on average) ALT : 7-41 U/L AST: 12-38 U/L AST can be found in various tissues like cardiac/skeletal muscles, kidney, brain and liver. ALT is limited primarily to the liver and thus ALT is a more specific reflection of hepatocellular disease than AST. The highest elevations of both enzymes are seen in viral, toxin-induced and ischemic hepatitis. On the other hand, alcoholic hepatitis usually gives a lower raise of around < 300 U/L. AST/ALT ratio is a useful indicator. a) A ratio of > 2 is highly suggestive of alcohol-induced hepatic injury. b) A ratio of > 1 and cirrhosis is often seen in patients of chronic hepatitis B infections. c) A ratio of < 1 ...