Antibodies to thyroglobulin (Anti TG)

Antibodies to thyroglobulin (anti-TG) It is produced against the precursor protein of thyroid hormones - thyroglobulin (TG).

Thyroglobulin (TG) Under normal conditions it is not excreted into the bloodstream. The passage of TG in the blood during various pathologies (inflammation, bleeding, etc.) can lead to the formation of antibodies against it.

Determination of thyroglobulin antibodies is important for the diagnostics of autoimmune diseases of the thyroid gland, for example: Hashimoto's disease, atrophic autoimmune thyroiditis, diffuse toxic goiter.

In patients with Hashimoto's thyroiditis, antibody levels usually decrease during treatment, but there are patients in whom the antibodies persist and may decrease in waves over 2-3 years.

Antibody levels in the blood correlate more with thyroid-stimulating hormone (TSH) levels than with thyroglobulin concentrations.

The determination of anti-TG for the detection of autoimmune diseases of the thyroid gland is especially justified in iodine-deficient regions. Children of mothers with high levels of antibodies may develop autoimmune thyroid diseases during their lifetime, requiring these children to be included in a high-risk group.

Antibodies to thyroglobulin are detected in 30–50% of patients with autoimmune thyroiditis and 30–49% of patients with Graves ’syndrome, as well as in 10–15% of patients with non-autoimmune thyroid disease.

Anti-TPO antibodies are a more sensitive marker of autoimmune thyroid pathology than anti-TG antibodies.

When should we test for thyroglobulin antibodies?

Anti-TG antibodies are markers of autoimmune thyroid damage and differentiated cancer recurrence.

• Diagnosis of autoimmune diseases of the thyroid gland;
• Detection of recurrence with thyroglobulin after ablation therapy of highly differentiated thyroid cancer;
• Before prescribing amiodarone, interferon and lithium drugs, assess the risk of developing thyroid pathology.

Testing for antibodies against thyroglobulin and peroxidase is essential for the diagnostics of autoimmune thyroiditis - Hashimoto's disease.

The sensitivity of diagnostic tests performed may be increased by simultaneous testing of anti-TG and anti-TPO and, in addition, the detection of antibodies to TSH receptors.

It should be remembered that a negative result does not rule out the presence of autoimmune disease of the thyroid gland.

Anti-TG antibodies may also be found in other autoimmune diseases, such as rheumatoid arthritis, systemic lupus erythematosus, and pernicious anemia.

Anti-TG antibodies may be present in small amounts in the serum of healthy individuals, especially adult women.

How to prepare for the test?

Take the test preferably on an empty stomach, in the morning In hours (Until about 11 p.m.).

Research material

Venous blood

Possible interpretation of the results

Elevated levels of thyroglobulin antibodies:

• Autoimmune thyroiditis (Hashimoto's disease);
• Diffuse toxic goiter (Graves' disease);
• Idiopathic hypothyroidism;
• Down syndrome (weakly positive result);
• Recurrence after highly-differentiated thyroid cancer ablation therapy.