GGT (GAMMA GLUTAMYL TRANSFERASE)

GGT (GAMMA GLUTAMYL TRANSFERASE)

Gamma-glutamyl transferase (GGT) is an enzyme that is found in many organs throughout the body, with the highest concentrations found in the liver. GGT is elevated in the blood in most diseases that cause damage to the liver or bile ducts. This test measures the level of GGT in a blood sample.

GGT is present in low levels, but when the liver is injured, the GGT level can rise. GGT is usually the first liver enzyme to rise in the blood when any of the bile ducts that carry bile from the liver to the intestines become obstructed, for example, by tumors or stones. This makes it the most sensitive liver enzyme test for detecting bile duct problems.

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.Increased levels of GGT can indicate diseases of the liver, kidneys, gallbladder, bile ducts and/or pancreas.

A GGT test may be ordered when you have an elevated ALP level. An ALP test may be ordered alone or as part of a routine liver panel to screen for liver damage, even if no symptoms are present. A GGT test may be ordered when results of the ALP test are high but other tests that are part of the liver panel (such as AST and ALT) are not increased.