antithyroid peroxidase antibody

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July 17, 2026

Quick Summary

Antithyroid peroxidase (anti-TPO) antibodies are proteins found in the blood that the body produces when it mistakenly attacks its own thyroid gland. These antibodies target thyroid peroxidase, an enzyme crucial for thyroid hormone production.1

High levels of anti-TPO antibodies are a common indicator of Hashimoto disease, an autoimmune disorder where the immune system gradually destroys thyroid tissue, leading to hypothyroidism (underactive thyroid). They are also frequently present in individuals with Graves' disease, another autoimmune thyroid condition that causes hyperthyroidism (overactive thyroid). Measuring these antibodies is a key diagnostic tool for thyroid autoimmune diseases.123

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thyroid function test
…antibodies found in serum, namely antithyroid peroxidase antibodies, antithyroglobulin antibodies, and antibodies that act like thyrotropin (called TSH-receptor antibodies). Most patients with Hashimoto disease have high serum concentrations of antithyroid peroxidase and antithyroglobulin antibodies. Many patients with Graves disease have high serum
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…antibodies found in serum, namely antithyroid peroxidase antibodies, antithyroglobulin antibodies, and antibodies that act like thyrotropin (called TSH-receptor antibodies). Most patients with Hashimoto disease have high serum concentrations of antithyroid peroxidase and antithyroglobulin antibodies. Many patients with Graves disease have high serum
Read More