THYROID PEROXIDASE ANTI- BODIES (ANTI TPO) , SERUM

Thyroid Peroxidase Antibodies (Anti-TPO), Serum

What it is

The Thyroid Peroxidase Antibodies (Anti-TPO), Serum test measures antibodies directed against thyroid peroxidase, an enzyme in the thyroid gland that plays a key role in producing thyroid hormones (T3 and T4). The presence of Anti-TPO antibodies indicates an autoimmune attack on the thyroid gland and is strongly associated with autoimmune thyroid diseases.

Uses

This test is primarily used to help diagnose autoimmune thyroid disorders such as Hashimoto’s thyroiditis and Graves’ disease. It is also useful in evaluating patients with abnormal TSH, FT3, or FT4 results, monitoring thyroid function in pregnancy, and identifying individuals at risk of developing hypothyroidism.

Symptoms That May Lead to the Test

Doctors may recommend this test if you have symptoms suggestive of thyroid dysfunction. For hypothyroidism: fatigue, weight gain, constipation, depression, cold intolerance, or hair loss. For hyperthyroidism: weight loss, anxiety, palpitations, tremors, heat intolerance, or sweating. It may also be ordered in cases of enlarged thyroid (goiter) or a family history of autoimmune disease.

Abnormal Results

Positive Anti-TPO Antibodies: Strongly suggest autoimmune thyroid disease such as Hashimoto’s thyroiditis (most common cause of hypothyroidism) or Graves’ disease (common cause of hyperthyroidism). Elevated levels may also be found in some healthy individuals, especially women and the elderly.

Negative Anti-TPO Antibodies: Suggests a lower likelihood of autoimmune thyroid disease, though thyroid dysfunction may still occur from non-autoimmune causes.

Risks

The test requires a standard blood draw. Risks are minimal and may include mild bruising, pain, or dizziness at the puncture site. There are no long-term risks associated with this procedure.