TSH Receptor Antibody Test - Anti-TSH Receptor Antibodies (TRAb) Test

The thyroid-stimulating hormone receptor (TRAb) antibody test is a quantitative immunoassay that detects and measures autoantibodies directed against TSH receptors on the surface of thyroid cells. These antibodies (especially the TSI type) mimic TSH, binding to and continuously activating the receptors, leading to overproduction and secretion of thyroid hormones (T3 and T4) and pituitary atrophy (low TSH). It is the most specific test for diagnosing Graves' disease.