Biomarker · Thyroid
Thyroid antibodies (TPO and thyroglobulin antibodies)
Thyroid antibody tests look for an immune reaction against the thyroid. What TPO and thyroglobulin antibodies indicate and how they relate to Hashimoto's and Graves' disease.
Written by LON6EVITY Editorial Team · Last updated
What the test looks for
Thyroid antibodies are made when the immune system mistakenly targets the thyroid. MedlinePlus lists the main types as thyroid peroxidase antibodies (TPO), thyroglobulin antibodies (TgAb) and TSH receptor antibodies (TRAb).
Why it matters
Antibody tests help identify autoimmune thyroid disease. NIDDK explains that Hashimoto's disease, the most common cause of hypothyroidism in the United States, is an autoimmune condition, and that TPO antibodies are found in most people with it. TSH receptor antibodies are associated with Graves' disease.
What a positive result means
Some people have thyroid antibodies with normal thyroid function. A positive result does not by itself mean treatment is needed; clinicians usually follow thyroid function over time.
Factors that can affect the result
- Autoimmune thyroid disease
- Family history
- Pregnancy
- Other autoimmune conditions
Questions people commonly ask
- Can I have antibodies and a normal thyroid?
- Yes. Antibodies can be present for years before, or without, any change in thyroid hormone levels.
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Understand your biomarkers in context
What does this mean for your own health data? Log your results, follow trends over time and bring an organised summary to your next doctor's appointment.
Sources
- Thyroid Antibodies. MedlinePlus, U.S. National Library of Medicine.
- Hashimoto's Disease. National Institute of Diabetes and Digestive and Kidney Diseases (NIH).