Gamma-Glutamyl Transferase (GGT) Blood Test

What is the purpose of this test?

Order this Gamma-Glutamyl Transferase (GGT) Blood Test, which measures GGT levels in the blood to screen for liver or bile duct disease. Gamma-glutamyl transferase (GGT) is an enzyme found in several organs, with the liver having the highest levels. Elevated GGT levels in the blood indicate damage to the liver or bile ducts. The GGT test can help identify the cause of elevated alkaline phosphatase (ALP) levels. Both ALP and GGT can be elevated in bile duct diseases and some liver diseases, but only ALP is elevated in bone diseases. Thus, if the GGT level is within the reference range and ALP is high, the most probable cause is bone disease.

The GGT test is often utilized to aid in the detection of liver disease and bile duct obstructions. It is typically ordered alongside or following other liver tests such as ALT, AST, ALP, and bilirubin. A heightened GGT level generally signifies liver damage but does not specifically indicate the underlying cause. GGT can be used to screen for chronic alcohol abuse, as it is elevated in approximately 75% of chronic drinkers, and to monitor alcohol use and abuse in those receiving treatment for alcoholism or alcoholic hepatitis.

When should I order a GGT Blood Test?

Individuals may order this test if they have experienced liver or bile duct disease symptoms. Common signs or symptoms of these conditions include:

• Weakness and fatigue
• Loss of appetite
• Nausea and vomiting
• Abdominal swelling or pain
• Jaundice
• Dark-colored urine
• Light-colored stool
• Itching