Thyroid Peroxidase Antibody (TPOAb)

What is Thyroid Peroxidase Antibody?

Thyroid peroxidase (TPO) is an enzyme found in the thyroid gland that plays a crucial role in thyroid hormone (T4 and T3) synthesis. TPO Antibodies (TPOAb), also known as antithyroid peroxidase antibodies, are found in some individuals whose immune systems mistakenly target the thyroid gland and produce antibodies against TPO. The presence of these antibodies is indicative of potential dysfunction of the thyroid gland.

Why is it included in Thyroid+?

Tracking your TPOAb level allows you to understand the health of your thyroid gland, which is an integral part of your endocrine system. Thyroid hormones are vital to metabolism, heart and digestive functions, muscle control, brain development, and bone maintenance, among other roles, so abnormal TPOAb could affect your overall health and wellness. Because of its significance as an indicator of chronic disease and cancer, TPOAb is included in SiPhox Health's Thyroid+ panel.

The TPOAb test is usually suggested for people who are experiencing hypothyroidism or hyperthyroidism to determine whether an autoimmune disease is the underlying cause. One common autoimmune disease, Hashimoto's, is typically accompanied by weight gain, fatigue, hair loss, low tolerance for cold temperatures, irregular periods, constipation, depression, and joint pain. Graves' disease, on the other hand, has symptoms including weight loss, bulging eyes, hand tremors, low heat tolerance, trouble sleeping, anxiety, increased heart rate, and an enlarged thyroid gland.

How can I better understand my results?

According to Mayo Clinic Laboratories, normal levels of TPOAb are < 9.0 IU/mL. If your TPOAb results are raised, please consult with your physician as this may be indicative of an autoimmune disease such as Hashimoto's disease or Graves' disease, and although less common, could be a marker for cancer. According to British Thyroid Foundation, while ~90% of people with elevated TPOAb have an autoimmune disease, ~10% do not have thyroid disease at all. Therefore, interpretation of your results is best left to a physician.

If your TPOAb levels are high, you can try:

    Where can I learn more?

    MedlinePlus - Thyroid Antibodies

    Connected Rheumatology (video) - What your doctor wants you to know about your +TPO antibody