Abstract: Abstract 0bjective: We evaluated clinical value of fully automated electrochemiluminescence immunoassay (ECLIA) for measuring serum TRAb. Methods: Totally 150 Graves’disease（GD）, 56 Hashimoto’s thyroiditis（HT）,73 subacute thyroiditis(ST) and 95 healthy subjects(HS) were retrospectively evaluated by both ECILA and radioactive receptor assay(RRA). The optimal cut-off which was calculated by receiver operating characteristic (ROC).Results: The cut-off value of 1.85 IU/L from the ROC on the GD cases was chosen as the cut-off with 94.7% of sensitivity and 91.6% of specificity. The area under the ROC curve was 0.935. The new automated assay was superior to RRA. Conclusion: Results demonstrate that this fully automated system has a high sensitivity and speci?city for diagnosis GD, especially for identifying it from various forms of thyrotoxicosis.. This assay may represent the future technology for TRAb detection.

Key words: TSH receptor antibody, electrochemiluminescence immunoassay, Graves’disease, curve of receiver operating characteristic