These occur when yourimmune systemattacks your own tissues.
If you have symptoms ofthyroid disease, antibody tests may be ordered to look for these proteins.
This article discusses anti-thyroid antibodies, what they do, and why you may need to undergo testing.
Verywell / Laura Porter
It will also help you understand what your test results mean.
Anti-Thyroperoxidase Antibodies (TPOAb)
Anti-thyroperoxidase antibodies (TPOAb) targetthyroid peroxidase (TPO).
TPO assists the chemical reaction that adds iodine (an important nutrient) to a protein called thyroglobulin.
This is a critical step in generating thyroid hormones.
Anti-TPO antibodies stop TPO from using iodine.
This causes hypothyroidism, in which your thyroid gland doesn’t produce enough thyroid hormones.
Anti-TPO antibodies are found in around 90% of people with Hashimoto’s disease.
For example, people with Hashimoto’s disease often have low T3 and T4 levels but high TSH levels.
At the same time, it can take time for anti-TPO antibodies to effect changes in TSH levels.
Some people with anti-TPO antibodies never become hypothyroid.
As such, high levels of TSHR antibodies are strongly suggestive of Graves' disease.
The TSHR-Ab test is sometimes called the thyroid-stimulating immunoglobulin (TSI) test.
Anti-Tg antibodies attack thyroglobulin, reducing the output of thyroid hormones and leading to hypothyroidism.
Thyroid Antibody Test Results
Verywell / Laura Porter
Antibody levels can be tested with a blood sample.
Treatment is based on symptoms and TSH, T4, and T3 levels.
Antibody tests are useful in finding the cause of your thyroid disease.
They can also help identifysubclinical thyroid disease, which is thyroid disease with mild or no symptoms.
Positive thyroid antibodies suggest youcouldhave autoimmune thyroid disease.
Still, they are only a piece of the picture.They can help healthcare providers decide if treatment is needed.
Healthcare providers will also consider your symptoms, family history, and other blood test results.
you might have elevated thyroid antibodies and not require treatment.
If you have mild symptoms or your thyroid levels are borderline, you are more likely to receive treatment.
The presence of antibodies may confirm subclinical hypothyroidism.
Early therapy might prevent disease progression, but this has not been proven.
Summary
Some thyroid conditions are due to autoimmune disorders.
These are conditions where the body produces antibodies that interfere with the thyroid hormone-making process.
Thyroid antibodies may cause the thyroid to make too much or not enough thyroid hormone.
An antibody test can determine the cause of your condition.
Thyroid treatment is based on your symptoms.
If you do not have symptoms, you may not need treatment.
This can lead to autoimmune thyroid diseases.
If you experience thyroid issues, a healthcare provider may order tests to check for these antibodies.
Early detection and proper management can help maintain good thyroid health.
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