Thyroid Peroxidase (TPO) is an enzyme found in the thyroid gland. TPO has an important role in the production of thyroid hormones. A TPO or anti-TPO test detects antibodies against TPO in the individual's blood.
A physician may request the Anti-Thyroid Peroxidase Antibody or Anti-TPO test, among other thyroid tests, in patients suspected or diagnosed with thyroid disease.
The thyroid is a small gland located near the throat. The thyroid makes hormones that regulate the way the body uses energy. It also plays an essential role in regulating an individual's weight, muscle strength, and body temperature.
Antibodies are proteins the immune system produces to fight foreign pathogens like viruses, parasites, and bacteria. Sometimes antibodies can attack the body's cells, tissues, and organs by error. This is known as an autoimmune defect. When thyroid antibodies attack thyroid cells, it can lead to an autoimmune disorder of the thyroid, which can cause health issues if not properly treated.
TPO antibodies in the patient's blood may indicate a thyroid disease with an autoimmune cause, such as Graves or Hashimoto's disease.
Antibodies that attack the thyroid gland can cause swelling and reduced thyroid function.
The physician may order an anti-TPO test if a woman is pregnant and has an autoimmune disease involving the thyroid or if the physician suspects an autoimmune thyroid disease.
It is important to note that some people with detected TPO antibodies in the blood may not have thyroid disease. But the presence of TPO antibodies may increase their risk of developing future thyroid disorders.
This is a single-marker test measuring thyroid peroxidase (TPO) antibodies.