{"id":"trab","name":"TSH Receptor Antibodies (TRAb / TBII)","shortName":"TRAb","aliases":["TSH Receptor Antibody","TRAb","TBII","Thyrotropin Receptor Antibody","Thyrotropin Binding Inhibitory Immunoglobulin","Thyrotropin Receptor Ab","Anti-TSH Receptor Antibodies","TSHR Ab","TSH-R-Ab","Thyrotropin Receptor Ab, Serum","TSH Receptor Antibodies","Thyrotropin Receptor Antibodies","Anti-TSHR","Anti-TSH Receptor Antibody"],"abbreviations":["TRAb","TBII","TSHR Ab","TSH-R-Ab"],"loinc":[{"code":"5385-0","primary":true},{"code":"57416-0","primary":false},{"code":"40673-6","primary":false},{"code":"82659-4","primary":false}],"specimen":"serum","units":[{"ucum":"[IU]/L","display":"IU/L"}],"referenceRanges":[{"population":"Adults","low":0,"high":1.75,"unit":"[IU]/L","unitDisplay":"IU/L","note":"Labcorp prints 0.0 to 1.75 units/L (electrochemiluminescence immunoassay). A result of 1.75 IU/L or less is negative on that method. The 1.75 cutoff matches the Roche Elecsys Anti-TSHR assay described in Nelson 2025, whose manufacturer reports 97% sensitivity and 99% specificity at this cutoff. Cutoffs are assay-specific, so other methods use different limits and results are not interchangeable. Use the cutoff and flag printed on your own report. In pregnancy, a result above three times the cutoff (above 5.25 IU/L on this method) is the level at which fetal monitoring is usually considered.","sources":[{"title":"Thyrotropin Receptor Antibody, Serum (test 010314)","url":"https://www.labcorp.com/tests/010314/thyrotropin-receptor-antibody-serum","publisher":"Labcorp"},{"title":"TSH Receptor Antibody Test Utilization Patterns From a National Reference Laboratory: TRAb, TSI, or Both?","url":"https://pmc.ncbi.nlm.nih.gov/articles/PMC12712957/","publisher":"Journal of Clinical Endocrinology & Metabolism","year":2025}]}],"review":{"status":"ai-verified","label":"AI-verified against cited sources. Awaiting expert review","lastReviewed":"2026-10-03"},"summary":"Antibodies that attach to the thyroid's TSH receptor. They are strongly linked to Graves' disease, an autoimmune cause of an overactive thyroid.","url":"https://bloodtesttracker.com/markers/trab","notice":"Information, not medical advice. Ranges differ between labs, so the range on your own report is the one your result is judged against."}