Thyroid peroxidase antibody (TPOAb)

Other names: Thyroid antibodies; Anti-thyroid antibodies; Thyroid stimulating hormone receptor antibody; Anti-TPO; Anti-microsomal antibody; Thyroid stimulating immunoglobulin; Antithyroglobulin antibody; Thyroid autoantibodies; Thyroglobulin antibody (TgAb); Thyroid microsomal antibody; TBII; TSI; TRAb

The thyroid antibody test checks for the presence of specific thyroid autoantibodies. Autoantibodies are produced when the body mistakes healthy thyroid tissue for foreign tissue; this can cause damage to the thyroid gland, inflammation of the gland (thyroiditis) and disruption of thyroid function.

When is the test used?

The test is used to help doctors diagnose autoimmune thyroid conditions and distinguish between conditions which have been caused by an autoimmune response and those that have been caused by other factors. The test is also used to monitor a patient’s condition once they have started a course of treatment.

The test is usually ordered when a patient has abnormal T3, T4 or THS tests or symptoms of goitre (this occurs when the thyroid gland is enlarged). The test is usually ordered when a patient has an autoimmune condition (such as lupus) which may be affecting the function of the thyroid gland.

How is the test done?

The test is done by taking a sample of blood from a vein in the patient’s arm; a needle is inserted into the vein and the blood is collected in a syringe. When the doctor or nurse has a sufficient sample, the blood will be bottled, labelled with the patient’s name and sent off to the laboratory for analysis.

What do the test results mean?

Slightly higher levels of thyroid antibodies are present in a range of health conditions, including colloidal thyroiditis.

Certain autoimmune disorders, including type 1 diabetes, pernicious anaemia and rheumatoid arthritis, may also cause thyroid antibodies to be present.

If levels are much higher than usual, this usually indicates that the patient has a thyroid autoimmune disease.

In some cases, healthy patients may test positive for one or more thyroid antibodies.

Specific Blood Tests



© Medic8® | All Rights Reserved