Lab comparison
γ-Glutamyl Transferase (GGT): Quest vs LabCorp vs BioReference, tube, code & requirements
. This page shows collection requirements for all three major reference labs in one view, so you don’t have to cross-check three portals.
Always verify against your lab’s current collection manual before drawing.
Every value on this page is verified by a nurse practitioner in active clinical practice, not scraped from an automated source.
| Requirement | Quest Diagnostics | LabCorp | BioReference |
|---|---|---|---|
| Test code | 482 | 001958 | 0093-5 |
| Primary tube | Serum separator tube (SST) | Red-top tube, gel-barrier tube, or green-top (lithium heparin) tube. Do not use oxalate, EDTA, or citrate plasma. | SST Tube |
| Specimen type | 1 mL serum | Serum (preferred) or plasma | 2 mL SST Tube |
| Patient prep | The patient should fast for eight hours prior to collection of the specimen. Since there are false elevations in patients on phenytoin and phenobarbital, such patients would be better served with orders for one of the alternate tests − leucine aminopeptidase (LAP) or 5′ nucleotidase. | The patient should fast for eight hours prior to collection of the specimen. Since there are false elevations in patients on phenytoin and phenobarbital, such patients would be better served with orders for one of the alternate tests − leucine aminopeptidase (LAP) or 5′ nucleotidase. | The patient should fast for eight hours prior to collection of the specimen. Since there are false elevations in patients on phenytoin and phenobarbital, such patients would be better served with orders for one of the alternate tests − leucine aminopeptidase (LAP) or 5′ nucleotidase. |
| Minimum volume | Minimum Volume 0.5 mL | Minimum Volume 0.7 mL (Note: This volume does not allow for repeat testing.) | Qty 1 |
Frequently asked questions
What is the Quest Diagnostics order code for γ-Glutamyl Transferase (GGT)?
The Quest Diagnostics order code for γ-Glutamyl Transferase (GGT) is 482.
What tube color does LabCorp use for γ-Glutamyl Transferase (GGT)?
LabCorp uses a Red-top tube, gel-barrier tube, or green-top (lithium heparin) tube. Do not use oxalate, EDTA, or citrate plasma. for γ-Glutamyl Transferase (GGT).
Does γ-Glutamyl Transferase (GGT) require fasting?
γ-Glutamyl Transferase (GGT) patient prep: The patient should fast for eight hours prior to collection of the specimen. Since there are false elevations in patients on phenytoin and phenobarbital, such patients would be better served with orders for one of the alternate tests − leucine aminopeptidase (LAP) or 5′ nucleotidase.. Always confirm with the ordering lab before the draw.
Data provenance
Source: Quest Diagnostics specimen collection manual, LabCorp directory of services, and BioReference laboratory collection guide.
Verified by: a licensed nurse practitioner in active clinical practice. Values are reviewed against each lab’s published collection requirements. Always confirm against your lab’s current manual before drawing.
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