The Anti-Thyroglobulin Antibody (Anti-Tg Ab) test detects autoantibodies against thyroglobulin, a protein produced by the thyroid gland that is essential for thyroid hormone production. It is primarily used to assess thyroid autoimmune diseases and to monitor thyroid cancer recurrence.
✅ Diagnosing autoimmune thyroid diseases (Hashimoto’s thyroiditis, Graves’ disease)
✅ Monitoring thyroid cancer patients after treatment
✅ Evaluating unexplained thyroid dysfunction (hypothyroidism or hyperthyroidism)
| Result | Interpretation |
|---|---|
| Negative (< 4 IU/mL) | No significant anti-thyroglobulin antibodies detected |
| Borderline (4-10 IU/mL) | Possible early or mild autoimmune thyroid activity |
| Positive (> 10 IU/mL) | Suggestive of an autoimmune thyroid disorder or past thyroid inflammation |
🔹 High Anti-Tg Ab levels are commonly found in Hashimoto’s thyroiditis (up to 80%) and Graves’ disease (40%).
🔹 Persistent Anti-Tg Ab positivity in thyroid cancer patients may indicate cancer recurrence.
Hashimoto’s Thyroiditis → High Anti-Tg Ab, elevated TSH, low T3/T4, progressive hypothyroidism.
Graves’ Disease → Anti-Tg Ab may be positive, but TSH receptor antibodies (TRAb) are more specific.
Thyroid Cancer → Used post-thyroidectomy to monitor for recurrence (along with thyroglobulin levels).
✔ TSH (Thyroid-Stimulating Hormone) → Primary screening for thyroid function.
✔ Free T3 & Free T4 → Measures active thyroid hormones.
✔ Anti-TPO (Thyroid Peroxidase Antibody) → More specific for Hashimoto’s thyroiditis.
✔ Thyroglobulin (Tg) → Used in thyroid cancer follow-up (low levels expected after treatment).
✔ TSI/TRAb (Thyroid-Stimulating Immunoglobulin / TSH Receptor Antibody) → Specific for Graves’ disease.
🔹 Evaluate thyroid function (TSH, Free T3/T4) for proper diagnosis.
🔹 Monitor symptoms of hypothyroidism (fatigue, weight gain, cold intolerance) or hyperthyroidism (weight loss, palpitations).
🔹 Consider imaging (thyroid ultrasound) if nodules or goiter are suspected.
🔹 Regular follow-ups with an endocrinologist for autoimmune thyroid disease or thyroid cancer monitoring.