The measurement of gamma-glutamyltransferase is used in the diagnosis and monitoring of hepatobiliary diseases and is by far the most sensitive enzymatic marker for liver diseases. The measurement of gamma-glutamyltransferase is still used for the laboratory differential diagnosis of increases in alkaline phosphatase. If the increase is due to bone disease, gamma-glutamyltransferase is normal, while if the increase in alkaline phosphatase is due to hepatocellular disease, gamma-glutamyltransferase is increased.
Gamma-glutamyltransferase (γ-GT, gamma-GT) is an enzyme found mainly in the bile and liver and to a lesser extent in the heart, kidneys, pancreas, brain, salivary glands, prostate and spleen. The function of gamma-glutamyltransferase is related to the transfer of amino acids through the cell membranes. Gamma-GT is often measured in combination with alkaline phosphatase (ALP) to determine whether ALP is elevated due to liver disease. While ALP can be elevated in either hepatocellular or bone disorders, gamma-GT is increased only in hepatocellular disorders. Gamma-GT is more sensitive to ALP, transaminases (SGOT and SGPT) and leucine aminopeptidase, in the detection of obstructive jaundice, cholangitis and cholecystitis.
High meat intake and low fruit consumption can increase serum gamma-GT levels.
Possible Interpretations of Pathological Values
- Increase: Paracetamol toxicity, alcoholism, alpha1-antitrypsin deficiency, biliary atresia, cholecystitis (caused by biliary obstruction), cholestasis (intrahepatic), cirrhosis (biliary, Laennec's), cardiac arrest, congestive heart disease, fatty liver disease, liver carcinoma (metastatic), hepatitis (acute, chronic), parenteral nutrition-related cholestasis, jaundice (obstructive), Kawasaki disease, lipoid nephrosis, liver disease, metabolic syndrome, infectious mononucleosis, myocardial infarction, pancreatic cancer, pancreatitis (acute), primary biliary cirrhosis, renal carcinoma, systemic lupus erythematosus. Medications: alcohol, glutethimide, high doses of 5-FU, methaqualone, phenobarbital, phenytoin, phenytoin sodium, rosiglitazone.
Laboratory test results are the most important parameter for the diagnosis and monitoring of all pathological conditions. 70%-80% of diagnostic decisions are based on laboratory tests. The correct interpretation of laboratory results allows a doctor to distinguish "healthy" from "diseased".
Laboratory test results should not be interpreted from the numerical result of a single analysis. Test results should be interpreted in relation to each individual case and family history, clinical findings, and the results of other laboratory tests and information. Your personal physician should explain the importance of your test results.
At Diagnostiki Athinon we answer any questions you may have about the test you perform in our laboratory and we contact your doctor to get the best possible medical care.