Clinical Significance

Elevated GGT is found in all forms of liver disease. Measurement of GGT is used in the diagnosis and treatment of alcoholic cirrhosis, as well as primary and secondary liver tumors. It is more sensitive than alkaline phosphatase, the transaminases, and leucine aminopeptidase in detecting obstructive jaundice, cholangitis, and cholecystitis. Normal levels of GGT are seen in skeletal diseases; thus, GGT in serum can be used to ascertain whether a disease, suggested by elevated alkaline phosphatase, is skeletal or hepatobiliary.