Gamma Glutamyl Transferase (GGT)

Test Code

38450

CPT Codes
82977<br>Limited Access Code

Preferred Specimen

1 mL serum collected in a serum separator tube (SST)

Minimum Volume

0.5 mL

Other Acceptable Specimens

Plasma collected in a plasma separator tube (PST)

Transport Temperature

Room temperature

Specimen Stability

Room temperature: 7 days
Refrigerated: 7 days
Frozen: 28 days

Methodology
Spectrophotometric

Setup Schedule

Set up: Daily; Report available: Next day

Reference Range

Age	Male (U/L)	Female (U/L)
<6 months:	12-122	15-132
6-11 months:	≤39	≤39
1-12 years:	3-22	3-22
13-15 years:	8-32	7-18
16-19 years:	9-31	6-26
20-29 years:	3-70	3-40
30-39 years:	3-90	3-50
40-54 years:	3-95	3-55
55-59 years:	3-85	3-70
≥60 years:	3-70	3-65

Clinical Significance

Elevated GGT is found in all forms of liver disease. Measurement of GGT is used in the diagnosis and treatment of alcoholic cirrhosis, as well as primary and secondary liver tumors. It is more sensitive than alkaline phosphatase, the transaminases, and leucine aminopeptidase in detecting obstructive jaundice, cholangitis, and cholecystitis. Normal levels of GGT are seen in skeletal diseases; thus, GGT in serum can be used to determine whether a disease, suggested by elevated alkaline phosphatase, is skeletal or hepatobiliary.

The CPT Codes provided in this document are based on AMA guidelines and are for informational purposes only. CPT coding is the sole responsibility of the billing party. Please direct any questions regarding coding to the payor being billed. Any Profile/panel component may be ordered separately. Reflex tests are performed at an additional charge.