Gamma-glutamyl transpeptidase

Label Mnemonic:	GGT
Epic code:	LAB85
Downtime form:	Doctor/Provider Orders - Pathology Core and Specialty Care Nursery

Chemistry
6240 RCP
356-3527

Specimen(s):

Plasma

Collection Medium:

Plasma Separator Tube 4.5 mL

Alternate Collection Media:

Call laboratory for additional acceptable specimen collection containers.

Minimum:

3 mL whole blood in light green top tube or ONE Microtainer^® for pediatric patients

Testing Schedule:

24 hrs/day, 7 days a week, including holidays.

Turn Around Time:

1 hour (upon receipt in laboratory)

Reference Range:

Male   8-61 U/L
Female 5-36 U/L

Comments:

Elevated by drugs such as Phenobarbital and Dilantin. See reference range change.

This test is also performed in the Iowa River Landing (IRL) clinical laboratory (for specimens drawn at that site).

Test Limitations:

Criterion: Recovery within plus or minus 10% of initial value. 

Icterus: No significant interference up to an I index of 50 
(approximate unconjugated bilirubin concentration:35 mg/dL). 

Hemolysis: No significant interference up to an H index of 200 mg/dL 
(approximate hemoglobin concentration: 200 mg/dL). 

Lipemia (Intralipid): No significant interference up to an L index of 
700 mg/dL (approximate triglycerides concentration: 1400 mg/dL).There 
is poor correlation between turbidity and triglycerides concentration.

Reference:
Glick MR, Ryder KW, Jackson SA. Graphical Comparisons of Interferences 
in Clinical Chemistry Instrumentation. Clin Chem 1986;32:470-474.

Methodology:

Enzymatic

CPT Code:

82977