Laboratory: Clinical Biochemistry
Test Name:
Test Code: THGL
Clinical Information:
Test Indications:  Thyroglobulin is produced in the thyroid gland  and is involved in the synthesis of T3 and T4. The main application of thyroglobulin testing is in the post operative follow-up of patients with differentiated thyroid carcinoma (DTC).
Anti-thyroglobulin testing is automatically performed on all specimens tested for thyroglobulin. This is to rule out the presence of thyroglobulin antibodies that can affect the thyroglobulin assay. Anti-TG testing is not performed when thyroglobulin levels are >2000 µg/L.
Patient Preparation Instructions:  Multivitamins (45–125 µg biotin) or biotin-only supplements up to 1 mg per day do not interfere with this test. Samples should not be taken from patients receiving therapy with high biotin doses (i.e. >5 mg/day) until at least 8 hours after the last dose.
Collection Devices:
Li Heparin samples are not acceptable.
Specimen Required:

Serum: 2.0 mL

Stability 3 days refrigerated, 1 month frozen
Serum: 2.0 mL

Samples must be transferred to an aliquot tube and stored frozen if analysis will not be performed within 48 hours (#110-10-05 Serum/Plasma Separation Procedure & Transport)
Reference Values:
Athyroidic Patient:      < 0.1 μg/L
Normal Thyroid:   3.5 - 77 μg/L
See Also:
More Information: