Gamma Glutamyl Transferase, Serum or Plasma

Casandra

Casandra Test Code AR83015Version 1 (DRAFT)

Performing Lab

Lab ARUP LaboratoriesLab Test ID 0020009CPT Code 82977

Gamma Glutamyl Transferase, Serum or Plasma

Also known as: GT

Clinical Use

Order Test

Use

The Gamma Glutamyl Transferase (GGT) test is used as an indirect marker for alcohol abuse, nonalcoholic fatty liver disease, drug intoxication, or other liver disorders. It helps in the evaluation of liver function and can be used in conjunction with other tests for a comprehensive liver assessment. Elevated GGT levels are often indicative of liver damage or bile duct problems. Testing for GGT may aid in diagnosing liver diseases, monitoring the effects of alcohol consumption, or evaluating patients with suspected liver dysfunction.

Special Instructions

For accurate results, the serum or plasma should be separated from cells within 2 hours of collection and transferred to an ARUP Standard Transport Tube. Specimens should be stored and transported refrigerated. It is essential to prevent hemolysis, as grossly hemolyzed specimens are unacceptable and will lead to rejection. Patient adherence to specimen preparation and collection standards is crucial for reliable test results.

Limitations

The GGT test is specific for liver enzyme activity, but it cannot differentiate between different types of liver diseases on its own. While elevated GGT levels suggest liver dysfunction, additional testing is often required to pinpoint the exact cause. GGT levels can also be raised due to factors like alcohol consumption, certain medications, and other non-liver-related health conditions. Interference from hemolysis can invalidate results, as can improper handling and storage, making it critical to adhere to collection instructions. It is not suitable as a standalone diagnostic test and should be used in conjunction with other clinical evaluations for a comprehensive view.

Test Details

FDA Approved

New York Approved

Methodology

Automated Analyzer (Clinical Chemistry)

Biomarkers

Gamma Glutamyl Transferase

Other

Enzyme Activity • Concentration / Level • Quantitative (Continuous) (e.g., copies/mL, % expression)

LOINC Codes

Result Codes

2324-2

Result Turnaround Time

1 day

Specimen

Plasma

Volume

1 mL

Minimum Volume

0.2 mL

Container

Serum separator tube or plasma separator tube, also acceptable: Green (lithium heparin)

Collection Instructions

Allow serum tube to clot completely at room temperature. Separate serum or plasma from cells within 2 hours of collection. Transfer 1 mL serum or plasma to an ARUP Standard Transport Tube.