Useful For

γ-Glutamyltransferase plays a major role in glutathione metabolism and in resorption of amino acids from the glomerular filtrate.  It is also important in the absorption of amino acids from the intestinal lumen.  GGT is found mainly in the liver, pancreas, and kidney, although lower activities can be demonstrated in most other organs.

Serum GGT is a sensitive indicator of hepatobiliary disease and is useful in the diagnosis of obstructive jaundice and chronic alcoholic liver disease, in the follow-up of chronic alcoholics undergoing treatment, and in the detection of hepatotoxicity.  GGT is more responsive to biliary obstruction than AST, ALT, or ALKP. GGT is also increased in hepatoma, carcinoma of the pancreas, and carcinoma metastatic to the liver.