An advanced thyroid function blood test provides a comprehensive evaluation of thyroid health, going beyond the basic tests to include additional markers and assessments that can help diagnose complex thyroid disorders and provide more detailed information on thyroid function. Here are the key components typically included in an advanced thyroid function panel:

1. Thyroid-Stimulating Hormone (TSH)

  • Purpose: Primary test to assess thyroid function.
  • Normal Range: Typically between 0.4 and 4.0 mIU/L.

2. Free Thyroxine (Free T4)

  • Purpose: Measures the active form of thyroxine, providing information on thyroid hormone production.
  • Normal Range: Generally between 0.8 and 1.8 ng/dL.

3. Total Thyroxine (Total T4)

  • Purpose: Measures both free and protein-bound thyroxine.
  • Normal Range: Approximately 4.5 to 12.5 µg/dL.

4. Free Triiodothyronine (Free T3)

  • Purpose: Measures the active form of triiodothyronine, useful in diagnosing hyperthyroidism.
  • Normal Range: Generally between 2.3 and 4.2 pg/mL.

5. Total Triiodothyronine (Total T3)

  • Purpose: Measures both free and protein-bound triiodothyronine, which can help in diagnosing thyroid dysfunction.
  • Normal Range: Approximately 75 to 195 ng/dL.

6. Reverse T3 (rT3)

  • Purpose: Measures an inactive form of T3, useful for assessing non-thyroidal illness syndrome and certain cases of hypothyroidism.
  • Normal Range: Approximately 10 to 24 ng/dL.

7. Thyroid Antibodies in Advanced Thyroid Function Blood Test

  • Thyroid Peroxidase Antibodies (TPOAb):
    • Purpose: Detects autoimmune thyroid disease such as Hashimoto’s thyroiditis.
    • Normal Range: Typically less than 35 IU/mL.
  • Thyroglobulin Antibodies (TgAb):
    • Purpose: Another marker for autoimmune thyroid disease, particularly useful in thyroid cancer monitoring.
    • Normal Range: Typically less than 20 IU/mL.
  • Thyroid Stimulating Immunoglobulins (TSI):
    • Purpose: Specifically used to diagnose Graves’ disease.
    • Normal Range: Typically less than 140% of the baseline or negative.

8. Thyroglobulin (Tg)

  • Purpose: A protein produced by the thyroid gland, used as a tumor marker in patients with differentiated thyroid cancer.
  • Normal Range: Varies widely but typically less than 40 ng/mL in patients without thyroid cancer.

9. Calcitonin

  • Purpose: A hormone produced by the thyroid gland that helps regulate calcium levels. Elevated levels may indicate medullary thyroid cancer.
  • Normal Range: Less than 10 pg/mL.

10. Thyroid-Binding Globulin (TBG)

  • Purpose: Measures the protein that carries thyroid hormones in the blood, useful for interpreting total T4 and T3 levels.
  • Normal Range: Typically between 13 and 39 µg/mL.

11. Vitamin D Levels

  • Purpose: Vitamin D deficiency can affect thyroid function, and assessing levels helps in comprehensive thyroid health management.
  • Normal Range: 30-100 ng/mL.

12. Iron Levels (Ferritin, Total Iron-Binding Capacity)

  • Purpose: Iron deficiency can affect thyroid function; these tests provide information on iron stores and availability.
  • Normal Ranges:
    • Ferritin: 20-300 ng/mL for men, 20-150 ng/mL for women.
    • Total Iron-Binding Capacity: 240-450 µg/dL.

Preparation for Advanced Thyroid Function Blood Test:

  • Fasting: Generally not required, but follow any specific instructions from your healthcare provider.
  • Medication: Inform your healthcare provider about any medications or supplements you are taking, as they may affect test results.

Follow-Up and Management for Advanced Thyroid Function Blood Test:

  • Treatment: Depending on the diagnosis, treatment options may include thyroid hormone replacement, antithyroid medications, radioactive iodine, or surgery.
  • Monitoring: Regular follow-up tests are essential to monitor the effectiveness of treatment and adjust dosages as needed.

Consultation with an endocrinologist or healthcare provider specialising in thyroid disorders is crucial for accurate diagnosis, interpretation of advanced thyroid function tests, and tailored treatment plans.

Results – 2 days from Laboratory receiving sample

Back to Blood Tests