What is gamma-GT?
Gamma-GT stands for gamma-glutamyltransferase. It is an enzyme that transfers so-called amino groups. GGT is found in various organs of the body: liver cells harbor the largest proportion of the enzyme; however, gamma-GT is also found in mucosal cells of the small intestine, in the kidney and pancreas as well as in many other organs. However, the doctor can only measure the liver’s own gamma-GT in blood serum.
When is gamma-GT determined?
Gamma-glutamyl transferase is a very important parameter in the diagnosis of liver diseases. Symptoms that make the doctor think of liver damage include jaundice, right-sided upper abdominal pain and itching, but also non-specific general symptoms such as tiredness and fatigue. The following diseases, for example, may be behind such symptoms:
- Liver inflammation (hepatitis), especially viral hepatitis
- Liver damage due to alcohol
- Occlusive jaundice (jaundice due to a build-up of bile because its flow is obstructed, for example by a gallstone)
- Liver metastases in the context of cancer
- Diseases of the pancreas involving the liver
Liver values
Doctors use various laboratory values – the so-called liver values – to diagnose and monitor liver diseases: gamma-GT is one of them, as are GPT (ALT) and GOT (AST). The latter two are also enzymes. They are found inside the liver cells and are therefore only measured in elevated concentrations in the blood in cases of severe liver damage (cell destruction!). Gamma-glutamyl transferase, however, is bound to the membrane of the liver cells and therefore increases even in the case of mild liver damage.
Gamma-GT for abstinence monitoring
Doctors often determine the activity of gamma-GT to diagnose chronic alcohol abuse: people who regularly consume large amounts of alcohol have an elevated GGT in 80 to 90 percent of cases. If alcoholism is already known, the laboratory value can therefore be used to check abstinence during withdrawal therapy. However, patients who experience infrequent binge drinking do not have an altered GGT level.
Gamma-GT values: table with normal values
The gamma-GT blood values depend on age and gender. Values that deviate from the reference range may indicate liver disease. The level of the gamma-GT value is proportional to the extent of the liver damage and is therefore an indication of the severity of the disease: the higher the gamma-GT value, the greater the damage!
|
age |
Gamma-GT normal value |
|
Premature babies |
up to 292 U/l |
|
1 day |
up to 171 U/l |
|
2 to 5 days |
up to 210 U/l |
|
6 days to 6 months |
up to 231 U/l |
|
7 to 12 months of life |
up to 39 U/l |
|
1 to 3 years |
up to 20 U/l |
|
4 to 6 years |
up to 26 U/l |
|
7 to 12 years |
up to 19 U/l |
|
13 to 17 years |
up to 38 U/l for women up to 52 U/l for men |
|
adults |
up to 39 U/l for women up to 66 U/l for men |
When is the gamma-GT low?
If the GGT is low, this usually has no pathological value.
When is the gamma-GT elevated?
Diseases that manifest themselves with an elevated GGT are
- Bile stasis (cholestasis)
- Inflammation of the gallbladder and bile ducts (cholecystitis or cholangitis)
- Viral hepatitis (hepatitis A, B, C, D and E)
- Liver damage caused by toxins, for example tuber leaf fungus
- Liver damage due to alcoholism (liver cirrhosis, fatty liver)
- Pfeiffer’s glandular fever (mononucleosis, EBV infection)
Elevated gamma-GT
If you would like to know more about which diseases affect gamma-GT and to what extent, read the article Gamma-GT elevated.
What to do if gamma-GT is elevated?
What can I do as a patient with elevated gamma-GT?
Follow the treatment prescribed by your doctor for your underlying disease. You should also adopt a lifestyle that is gentle on your liver. This includes, above all, abstaining from alcoholic beverages. It also makes sense to give up smoking. Coffee, on the other hand, is still allowed and is even considered “good” for the liver. With regard to your diet, unless otherwise advised by your doctor, you should eat a balanced diet and avoid fatty and sweet foods. In this way, you can also help to keep your liver healthy in everyday life and reduce an elevated gamma-GT.
