Role of the GGT Blood Test in Diagnosing Diseases and Disorders of the Liver

If your physician suspects that you have damage or a condition of the liver, he or she may order a variety of tests. One of these is often the GGT blood test. When ordered alone it can provide small clues that may be indicative of malfunction of this particular organ. The results of the test can determine whether or not there is cause for alarm and if further testing is needed. In some cases, it may be repeated along with other tests to help confirm or deny certain health conditions.

What is the GGT?

The GGT blood test is also known as the Gamma-glutamyl transpeptidase test, your physician may also refer to it as the GGPT or the Gamma-GT. This simple blood test measures the amount of GGT in the blood stream. Abnormally low or high amounts can signify bile duct obstruction, bone disease and alcohol abuse to name a few. As a general rule of thumb, the higher the elevation of GGT that is present, the more indication that there may be liver damage. However, there are also other conditions that contribute to this and other tests will typically be ordered.

Associated Tests

Commonly, the ALP test is ordered along with the GGT blood test. In some cases, it will be ordered as a result of GGT test, while other times it is ordered prior to the GGT or in combination. This test can provide more insight regarding the particular condition and whether or not the problem is indeed caused by the liver. The ALP may be ordered to differentiate between disease of the liver and bone for example. Lower values of ALP typically indicate that a disease or disorder of the liver is unlikely. Other tests that may be ordered to check for disease or disorder of the liver include the liver panel test, AST, ALT and bilirubin levels may be screened as well.

Other Considerations

Abnormal values of one or both of these tests does not guarantee that the problem lies with the liver. Various things may affect the results of the tests. This can include medications, alcohol consumption and gender for example. Medications are not limited to prescription drugs; even some over the counter products and birth control pills can alter these tests. You should check with your physician prior to the appointment to discuss these concerns and any others that you may have.

Bibliography

GGT. Lab Tests Online. 7, January 2010. Viewed 13, August 2010. http://www.labtestsonline.org/understanding/analytes/ggt/test.html

Liver Function Tests: Why It's Done. Mayo Clinic. 17, July 2010. Viewed 13, August 2010. http://www.mayoclinic.com/health/liver-function-tests/MY00093/DSECTION=why-its-done