Anti-Thyroglobulin Antibody
CPT Code(s):
86800
Turnaround Time:
24 - 72 hours
Specimen Requirements
Preferred Specimen:
Serum
Minimum Volume:
1.0 mL
Transport Container:
Serum Separator Tube (SST) or Red Top Tube
Transport Temperature:
Room Temperature
Collection Instructions:
Separate serum from cells within one hour of collection. Transfer to a plastic transport tube before shipping. To avoid delays in turnaround time when requesting multiple tests on frozen samples, please submit separate frozen specimens for each test requested.
Rejection Criteria:
Grossly hemolyzed; lipemic specimen; icteric specimen; non - serum specimen types
Stability Criteria
Room Temperature:
8 hours
Refrigerated:
48 hours
Frozen:
30 days
Clinical Significance
The Anti-Thyroglobulin Antibody (Anti-Tg Ab) test holds specific clinical significance and diagnostic use in the field of endocrinology and autoimmune thyroid disorders. This test detects the presence of antibodies against thyroglobulin, a protein produced by the thyroid gland.
The clinical significance and diagnostic use of the Anti-Tg Ab include:
1. Diagnosis of Autoimmune Thyroid Disorders: The presence of Anti-Tg antibodies is a hallmark of autoimmune thyroid disorders, such as Hashimoto's thyroiditis and Graves' disease. These conditions occur when the immune system mistakenly attacks the thyroid gland. The Anti-Tg Ab helps confirm the diagnosis of autoimmune thyroid disorders, particularly in conjunction with other thyroid function tests and clinical evaluation.
2. Differentiation of Thyroiditis Subtypes: The Anti-Tg Ab can help differentiate different subtypes of thyroiditis, including Hashimoto's thyroiditis and postpartum thyroiditis. Elevated Anti-Tg antibody levels, along with other clinical and laboratory findings, support the diagnosis of these conditions, aiding in appropriate treatment decisions and management.
3. Assessment of Thyroid Cancer: The Anti-Tg Ab is used in the management of thyroid cancer. After surgical removal of the thyroid gland (thyroidectomy), Anti-Tg antibodies can interfere with the interpretation of thyroglobulin levels as a tumor marker. Measuring Anti-Tg antibody levels helps healthcare providers interpret thyroglobulin results accurately and monitor for possible recurrence or metastasis in patients with thyroid cancer.
4. Prognostic Indicator in Thyroid Cancer: In some cases of thyroid cancer, the presence of Anti-Tg antibodies can have prognostic implications. High levels of Anti-Tg antibodies have been associated with a higher risk of recurrence and poorer outcomes in certain types of thyroid cancer. Monitoring Anti-Tg antibody levels can provide additional information for risk stratification and treatment planning.
5. Evaluation of Thyroid Dysfunction: Anti-Tg antibodies can interfere with thyroid function tests, leading to inaccurate results. In cases where thyroid function test results are inconsistent or contradictory, measuring Anti-Tg antibody levels can help identify potential interference and improve the interpretation of thyroid function test results.
In summary, the Anti-Thyroglobulin Antibody has specific clinical significance and diagnostic uses in diagnosing autoimmune thyroid disorders, differentiating thyroiditis subtypes, assessing thyroid cancer, providing prognostic information in thyroid cancer, and evaluating potential interference in thyroid function tests. By detecting Anti-Tg antibodies, this test aids in the diagnosis, management, and monitoring of various thyroid conditions, contributing to optimal patient care and treatment decisions.