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Gamma glutamyl transpeptidase (GGT or GGTP)
Gamma-glutamyltransferase measurements are used in the diagnosis and treatment of liver diseases such as alcoholic cirrhosis and primary and secondary liver tumors.
Elevated serum gamma-glutamyltransferase (GGT), sometimes called GGTP, is found in all forms of liver disease. It is more sensitive than alkaline phosphatase, the transaminases, and leucine aminopeptidase (LAP) in detecting obstructive jaundice, cholangitis, and cholecystitis. GGT levels rise earlier in liver disease and to higher values than LAP or 5’-nucleotidase levels. Moderate elevations are seen in infectious hepatitis. However, elevated GGT levels have also been noted in chronic alcoholism, diabetes, and certain neurological disorders. Normal levels of GGT are seen in skeletal diseases; thus GGT in serum can be used to ascertain whether a disease is skeletal or hepatobiliary.
GGT catalyzes the transfer of the gamma-glutamyl group from the substrate, gamma-glutamyl-3-carboxy-4-nitroanilide, to glycylglycine, yielding 5-amino-2-nitrobenzoate. The change in absorbance at 410/480 nm is due to the formation of 5-amino-2-nitrobenzoate and is directly proportional to the GGT activity in the sample.
Collect: Serum Separator Tube (SST) - 0.5 ml
Specimen preparation: Serum free from hemolysis is the recommended specimens. Allow blood samples to clot (15 mins). Separate the serum from the cells by centrifuging for 10 minutes. Store serum at 2-8°C until analysis.
Stability: The GGT determination should be performed as soon after specimen collection as possible. GGT in serum is stable for 1 month refrigerated at 2-8°C and 1 year frozen at <-20°C.
At Accu Reference: Refrigerated -7 days: Frozen- 1 monthPerforming Lab
NOTE: * This test is approved for all states. *
Accu Reference Medical Laboratory
|Cross Reference:||GGT (Gamma Glutamyl Transferase, Serum or Plasma), GT (Gamma Glutamyl Transferase, Serum or Plasma)|
Adults: 9 - 64 U/L
The assay Reportable Range is from 3.0 to 1200.0 U/L. Samples exceeding the upper limit of linearity are diluted and repeated.