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Test Code 137 Gamma Glutamyltransferase (GGT)

Important Note

The following drugs may elevate GGT results: ethanol, phenobarbitone, phenytoin, methaqualone, amyobarbitone, dichloralphenazone, quinalbarbitone and nitrazepam.

Additional Codes


PowerChart: GGT (Gamma Glutamyl Transferase)

MA Cerner: GGT Gamma Glutamyl Transferase.

Specimen Requirement

0.5 mL lithium heparin plasma or serum is required.

Additional Specimen Collection Information

Collect blood in a lithium heparin, green-top or red-top tube. PST and SST (gel tubes) are acceptable. Serum or plasma should be separated from contact with the cells within 2 hours of collection. Specimens not centrifuged within 4 hours of collection may be rejected. Refrigerate the specimen if unable to assay within 8 hours of collection. Hemolyzed specimens are not acceptable. Samples with >3+ lipemia must be cleared prior to analysis. If sample is stored longer than 48 hours, freeze at -15 to -20 C. Frozen samples should be thawed only once.

Useful For

Diagnosis and monitoring of hepatobiliary disease, it is currently the most sensitive enzymatic indicator of liver disease

To ascertain whether observed elevations of alkaline phosphatase are due to skeletal disease (normal GGT) or reflect the presence of hepatobiliary disease (elevated GGT)

A screening test for occult alcoholism


Testing is performed Monday through Sunday.

Routine orders: Typically completed within 4 hours; Mercy DV and MA East & West within 24 hours

Expedite orders: Typically completed within 1 hour after the specimen arrives at the testing site.

STAT orders: Typically completed within 30 minutes after the specimen arrives at the testing site.

CPT Code Information

82977 Chemistry: Glutamylransferase, gamma (GGT)

LOINC Code Information

2324-2 Gamma Glutamyl Transferase [Enzymatic Activity/Volume] In Serum Or Plasma

Test Method

MercyOne: Enzymatic Rate Method; Beckman DXC880i

MA: Enzymatic Colorimetric Method; Roche Cobas 6000

Reference Values

7-63 IU/L