What is another name for the Thyroid-Stimulating Immunoglobulin (TSI) test?

From the Guidelines

Another name for the thyroid stimulating immune globulin test is the Thyroid Stimulating Immunoglobulin (TSI) test or Thyroid Receptor Antibody (TRAb) test. This test is used to diagnose Graves' disease, a condition where the immune system produces antibodies that stimulate the thyroid gland to produce excess thyroid hormones, leading to hyperthyroidism 1. The TSI test measures the level of these antibodies in the blood, which can help healthcare providers diagnose and manage Graves' disease. According to the study published in the Journal for ImmunoTherapy of Cancer, thyroiditis and Graves' disease can occur as a result of immune checkpoint inhibitors, and the TSI test can be used to differentiate between these two conditions 1.

Some key points to note about the TSI test include:

• It is used to diagnose Graves' disease, which is a common cause of hyperthyroidism
• The test measures the level of antibodies that stimulate the thyroid gland to produce excess thyroid hormones
• It can be used to differentiate between thyroiditis and Graves' disease in patients taking immune checkpoint inhibitors
• The test requires a simple blood draw and no special preparation is needed beforehand
• Normal test results show no detectable TSI in the blood, while positive results indicate the presence of these antibodies and support a diagnosis of Graves' disease 1.

In clinical practice, the TSI test is an important tool for diagnosing and managing Graves' disease, and can help healthcare providers develop an effective treatment plan for patients with this condition.

From the Research

Alternative Names for Thyroid Stimulating Immunoglobulin Test

• Thyroid-stimulating immunoglobulins (TSI) are also referred to as:
  • Thyrotropin receptor antibodies (TRAb) 2, 3
  • Long-acting thyroid stimulator (LATS) 4
  • Thyroid-stimulating hormone receptor antibody (TSHR) 2
• These alternative names are used to describe the same test, which measures the levels of immunoglobulins that stimulate the thyroid gland 5, 6

Diagnostic Performance of TSI and TRAb

• The diagnostic performance of TSI and TRAb for Graves' disease has been evaluated in several studies 2, 3, 6
• TSI has been shown to have excellent diagnostic performance for Graves' disease, with high sensitivity and specificity 3
• TRAb has also been shown to have high diagnostic accuracy for Graves' disease, with high sensitivity and specificity 3

Clinical Applications of TSI and TRAb

• TSI and TRAb are used to diagnose and monitor Graves' disease 2, 5, 3, 6
• They are also used to predict the risk of relapse in patients with Graves' disease treated with anti-thyroid drugs 6