What are thyroid-stimulating antibodies?
Thyroid-stimulating hormone receptor antibodies are also known as thyrotropin receptor antibodies and TSH receptor antibodies. The so-called ‘TRAK’ test detects the presence of thyroid antibodies associated with hyperthyroidism and is an important part of a full thyroid panel for someone with symptoms of thyroid problems.
Thyroid antibody tests are primarily ordered to help diagnose autoimmune hyperactive thyroid disease and to distinguish it from other forms of thyroid dysfunction.
Autoimmune is when the body attacks its own cells. Thyroid autoantibodies develop when a person's immune system mistakenly targets components of the thyroid gland or thyroid proteins, leading to chronic inflammation of the thyroid (thyroiditis), tissue damage, and/or disruption of thyroid function.
Trak is a method for measuring TSH-receptor antibodies. This test is ordered when a person has hyperthyroidism, to see if the cause of the elevated thyroid function is an autoimmune disease (Grave’s disease).
Why test TRAK?
Unless this is ordered as a retest or for a specific reason, we recommend ordering this as part of a health test. You may want to check whether you have TRAK antibodies for these reasons:
Health history
You have been or have previously been diagnosed with hyperthyroidism and wish to check your antibody levels
Symptoms
You have symptoms of hyperthyroidism, even if your thyroid results are within range
Pregnancy
20% of pregnant women have elevated antibodies without knowing about it, according to the American Thyroid Association.
Health check
This test can be included as part of a health and wellness check, for example during pregnancy.
Family history
You have a family history of hyperthyroidism and you have symptoms.
What does it mean if my thyroid antibody test is negative?
A negative result means that thyroid autoantibodies are not present in the blood at the time of testing. However, some people who have autoimmune thyroid disease do not have autoantibodies. Repeat testing at a later date can be done if symptoms persist.
What does it mean if my thyroid antibody test is positive?
This means that thyroglobulin antibodies were found in your sample. This may indicate an autoimmune thyroid disorder called Graves’ disease, which is an overproduction of thyroid hormones or hyperthyroidism.
Graves’ Disease is usually associated with symptoms of an overactive thyroid. T3 and T4 are usually high, and TSH is low. Hashimoto’s Thyroiditis on the other hand is mainly associated with symptoms of low thyroid function and high TSH (hypothyroidism).
Common symptoms of hyperthyroidism (overactive thyroid function) include unwanted/unexpected weight loss, rapid heartbeat, irregular heartbeat, nervousness, anxiety, irritability, tremor, enlarged thyroid gland (called goiter, that can be seen as a swelling at the base of your neck), sweating, changes in menstrual patterns, increased sensitivity to heat, changes in bowel movement especially more frequent ones, fatigue, muscle weakness, difficulty sleeping, thinning skin and brittle hair.
More information
Reference ranges may vary between laboratories. If you plan to order this test regularly for monitoring purposes, it is best to have it done by the same laboratory each time, using the same methodology.
Instructions
No advance preparation is required for this test.
On the day of the test
Do not take your thyroid medication until after you have taken this test. Remember to take your I.D. with you when going to take a test. Do not work out before going to do this test, as this may affect your results.
Take this test before 10 am, as results can vary throughout the day. If you are repeating a test, try to take it at the same time of day. Arrive early and sit down quietly for 15 minutes before the test is taken.