Thyroglobulin Antibody (Serum) – Immunoassay
This blood test measures antibodies against thyroglobulin, a protein produced by thyroid cells. It helps assess thyroid function and detect autoimmune thyroid diseases.
["This test may help diagnose or monitor thyroid conditions like Hashimoto’s thyroiditis."]
Key facts at a glance
- LOINC
- 5381-9
- Short code
- Thyroglob Ab Titr Ser LA
- Synonyms
- Thyroglob Ab Titr Ser LA
- Category
- chemistry
- Sample
- serum
- Container
- Red-top tube (SST)
- Units
- N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- Method
- la
- Specimen volume
- 5 mL
- Stability
- Room temperature: 4h, Refrigerated: 24h, Frozen: 7d
- Hemolysis max
- 500
- Lipemia max
- 1000
- Icterus max
- 500
- TAT
- 4–24 hours
- Order
- routine
Why Is This Test Done?
Your healthcare provider may order this test if you have symptoms of an autoimmune thyroid condition, such as fatigue, weight changes, or an enlarged thyroid (goiter). It may also be used to monitor treatment in patients with thyroid cancer who have had radioactive iodine therapy.
What Does a Positive Result Mean?
A positive result suggests the presence of antibodies against thyroglobulin, which can indicate an autoimmune response targeting thyroid cells. This is often seen in conditions like Hashimoto’s thyroiditis or in some cases of thyroid cancer monitoring.
What Does a Negative Result Mean?
A negative result means no detectable antibodies against thyroglobulin were found in your blood. However, this does not rule out other thyroid-related conditions, so further evaluation may still be needed.
What Can Affect Test Results?
Several factors may influence thyroglobulin antibody levels, including other autoimmune diseases, recent infections, or medications that affect thyroid function. Your healthcare provider will consider these factors when interpreting your results.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
Thyroglobulin antibodies are primarily used to identify autoimmune thyroid diseases, such as Hashimoto’s thyroiditis. They can also play a role in monitoring thyroid cancer patients post-treatment to detect recurrence or residual disease. Elevated levels may indicate an ongoing immune response against thyroid tissue, which can impact thyroid hormone production and function.
Short name
Thyroglobulin Antibody (IgG)
Frequently asked questions
Will I Need to Prepare for This Test?
How Long Will It Take to Get Results?
Can I Have False Results?
Sources
- 1
- 2Lab Tests OnlineSource
- 3
Click any link to access the full source. PubMed Central (PMC) links provide free full-text access.
This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.
This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.
If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.
Medically reviewed by WellAlly Editorial Team Last reviewed August 16, 2026. · Read our editorial policy