TSH Receptor Antibody (TBII)

TSH receptor antibodies are antibodies that are often present in the serum of patients with Graves’ disease that are directed against the TSH receptor, often causing stimulation of this receptor with resulting hyperthyroidism.

What is Graves’ disease?

Graves' disease is an autoimmune disorder that can cause hyperthyroidism, or overactive thyroid. The thyroid is a small, butterfly-shaped gland in the front of your neck. Thyroid hormones control the way your body uses energy, so they affect nearly every organ in your body, even the way your heart beats.

Graves’ disease happens when the immune system of an individual makes specialized proteins called antibodies, which circulate in the blood then attach to the thyroid gland at a place called the TSH receptor. These TSH receptor antibodies then stimulate the thyroid to make excess amounts of thyroid hormone. Testing for these antibodies in patients with Graves’ disease is very helpful to make a diagnosis.

What is Hyperthyroidism?

Hyperthyroidism happens when the thyroid gland makes too much thyroid hormone. This condition also is called overactive thyroid. Hyperthyroidism speeds up the body's metabolism. That can cause many symptoms, such as weight loss, hand tremors, and rapid or irregular heartbeat.

A decrease in the level of TSH receptor antibodies during treatment with antithyroid medications can help determine the chances of the Graves’ disease going into remission. Interestingly, the level TSH receptor antibodies present in an individual falls over time regardless of the type of treatment used. In addition, some of the TSH receptor antibodies may switch function and will either stop stimulating the thyroid or even inhibiting the thyroid.