Serum Anti-Thyroglobulin (Anti-Tg)

Specimen Required

3-5cc Clotted Blood or Serum

Fasting Required

Purpose of the Test

The Anti-Tg test is primarily used to help diagnose and monitor autoimmune thyroid diseases, such as Hashimoto’s thyroiditis and Graves’ disease. It can also be used to monitor patients with thyroid cancer who have had their thyroid gland removed and to detect any recurrence of the cancer.

When this test is required

The Anti-Tg test may be requested when a person has signs and symptoms of autoimmune thyroid disease, such as fatigue, weight gain, hair loss, dry skin, and constipation. It may also be requested as part of a routine checkup to monitor patients with a history of autoimmune thyroid disease or thyroid cancer.

What the Test Detects

The Anti-Tg test measures the levels of antibodies against thyroglobulin, a protein produced by the thyroid gland. Thyroglobulin is involved in the production of thyroid hormones, which regulate metabolism and other important body functions. Antibodies against thyroglobulin are produced by the immune system in response to an autoimmune attack on the thyroid gland or as a result of thyroid cancer.

Preparation for the Test

No special preparation is needed for the Anti-Tg test.

Sample Requirements

The test requires a blood sample, which is usually drawn from a vein in the arm.

Additional Notes

The Anti-Tg test is just one of several tests that may be used to diagnose autoimmune thyroid disease or thyroid cancer, and a combination of clinical evaluation, laboratory tests, and imaging studies may be needed to make a definitive diagnosis. Treatment options for autoimmune thyroid disease depend on the severity of the disease and may include medications or surgery. Treatment options for thyroid cancer depend on the type and stage of the cancer and may include surgery, radiation therapy, chemotherapy, or targeted therapy.

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