A battery of blood tests which provide evidence of liver dysfunction and are used in diagnosis and monitoring of liver disease. They include enzymes which ‘leak’ out of damaged liver cells – alanine and aspartate aminotransferases (ALT and AST), gamma glutamyl transferase (gamma GT) which is particularly sensitive to alcohol intake, alkaline phosphatase (ALP) whose production is increased and albumin, which is reduced, when the liver is inflamed. Additional tests include checking the level of BILIRUBIN and a measure of blood coagulability depending on adequate liver metabolism of Vitamin K – the prothrombin time (PT).