Thyroglobulin Antigens

Cleveland Heartlab T, Test

CPT Code: 84432
Order Code: C2371
Includes: Thyroglobulin and Thyroglobulin Antibody Screen
ABN Requirement: No
Specimen: Serum
Volume:  1.0 mL
Minimum Volume:  0.5 mL
Container: Gel-barrier tube (SST, Tiger Top)



  1. Collect and label sample according to standard protocols.
  2. Gently invert tube 5 times immediately after draw. DO NOT SHAKE.
  3. Let tube stand in a vertical position to allow blood to clot 30 minutes.
  4. Centrifuge for 10 minutes.

Special Information: Patients taking a Biotin dose of up to 5 mg/day should refrain from taking Biotin for 2 days prior to sample collection. Patients taking a Biotin dose >5 mg/day to 10 mg/day should refrain from taking Biotin for 4 days prior to sample collection. Patients taking a Biotin dose >10 mg/day should consult with their physician or the laboratory prior to having a sample taken.

Transport: Store serum at 2-8°C after collection and ship the same day per packaging instructions provided with the Cleveland HeartLab shipping box.


Ambient (15-25°C): 24 hours
Refrigerated (2-8°C):
7 days
Frozen (-20°C):
60 days
Deep Frozen (-70°C):
60 days

Causes for Rejection: Specimens other than serum; improper labeling; samples not stored properly; samples older than stability limits

Methodology: Chemiluminescence Immunoassay (CLIA), Chemiluminescent Microparticle Immunoassay (CMIA)

Turn Around Time: 2-5 days

Reference Range:

Component Age ng/mL
Thyroglobulin All Ages 1.6-59.9


Component Age IU/mL
Thyroglobulin Antibody Screen All Ages <14.4


Clinical Significance: Serum thyroglobulin levels correlate well with the volume of differentiated thyroid tissue, hence are increased in thyrotoxicosis, thyroiditis, iodine deficiency, benign thyroid adenomas, and thyroid cancer. Thus, although it is unsuitable as a screening tool for differentiated thyroid cancer (DTC), it is a highly sensitive marker for the detection of residual or recurrent disease after a total thyroidectomy and successful radioiodine remnant ablation. Presence of thyroglobulin autoantibodies interfere with in the assay and thyroglobulin levels are underestimated in the antibody positive patients.

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.