Order Code: 30278
Includes: Thyroglobulin Antibodies and Quantitative Thyroglobulin
Alternative Name(s): TG and ATG; ATG and TG
ABN Requirement: No
Specimen: Serum
Volume: 2.0 mL
Minimum Volume: 1.0 mL
Container: Gel-barrier tube (SST, Tiger Top)
Collection:
Serum:
- Collect and label sample according to standard protocols.
- Gently invert tube 5 times immediately after draw. Do not shake.
- Let tube stand in a vertical position to allow blood to clot 30 minutes.
- Centrifuge for 10 minutes.
Patient Preparation: Dietary supplements containing biotin may interfere in assays and may skew results to be either falsely high or falsely low. For patients receiving the recommended daily doses of biotin, draw samples at least 8 hours following the last biotin supplementation. For patients on mega-doses of biotin supplements, draw samples at least 72 hours following the last biotin supplementation.
Administration of STRENSIQ may interfere in certain assays and may falsely elevate values. For patients receiving STRENSIQ, consideration should be given to alternate methods.
Transport: Store serum at 2-8°C after collection and ship the same day per packaging instructions included with the provided shipping box.
Stability:
Ambient (15-25°C): 7 days
Refrigerated (2-8°C): 7 days
Frozen (-20°C): 28 days
Causes for Rejection: Specimens other than serum; improper labeling; samples not stored properly; samples older than stability limits; gross hemolysis; gross lipemia
Methodology: Immunoassay (IA)
Turn Around Time: 2 to 5 days
Reference Range: See Laboratory Report
Clinical Significance: Thyroglobulin (TG) is a secretory product only of the thyroid gland. The major clinical use of serum TG measurement is to monitor, but not to diagnose, patients with well-differentiated thyroid cancers. The measurement of thyroglobulin, after thyroidectomy and ablation of the thyroid gland, is useful to determine metastasis.
Deficient TG synthesis is observed in infants with goitrous hypo-thyroidism. Most patients with thyroid autoimmune disease have thyroglobulin antibody. With immunometric assays (sandwich assays), TGAB interference typically produces inappropriately low TG results, most likely caused by endogenous TG immune complexes that block one or more of the reagent antibodies from binding endogenous TG.
The CPT codes provided 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 payer being billed.