High concentrations of GGT are found in the liver, bile ducts, and
the kidney. Hence kidney and urinary
problems could be causing the high GGT level. Greater-than-normal levels of GGT may indicate: congestive heart failure , cholestasis (congestion of the bile ducts) , cirrhosis, hepatitis , liver ischemia (blood flow deficiency), liver necrosis, liver tumor, high alcohol intake, use of hepatotoxic drugs (drugs toxic to liver).