Thyroid Peroxidase Antibodies (Anti-TPO)
Hormone markersWhat the test generally measures, and what to ask about it.
Longetic keeps every lab and record you’ve had organized and easy to find, so your own Thyroid Peroxidase Antibodies (Anti-TPO) values sit together on one chart and you walk into your next appointment prepared.
What is Thyroid Peroxidase Antibodies (Anti-TPO)?
Immune proteins that can mistakenly target the thyroid, often seen in autoimmune thyroid disease.
Anti-TPO antibodies are made by the immune system and can attack an enzyme in the thyroid, so measuring them helps tell whether a thyroid problem has an autoimmune cause. Higher levels can be associated with Hashimoto's disease (the most common cause of an underactive thyroid) and are sometimes seen in Graves' disease. This test is usually run after thyroid hormone tests (TSH, T4) already suggest the thyroid is over- or underactive, to explain why. Some healthy people carry low levels without disease, so the result is interpreted with symptoms, family history, and the other thyroid tests.
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