Autoantibody Testing for Patients with Hyperthyroidism

Two types of antibody tests can be used to diagnose autoimmune hyperthyroidism: Thyroid-stimulating hormone (TSH)–receptor antibody measurement, which identifies all antibodies that bind the TSH receptor, and the thyroid-stimulating immunoglobulin (TSI) assay, which detects only stimulating antibodies (see Figure 1). But is one test superior? And does ordering both tests add diagnostic value?

To investigate these questions, researchers analyzed test-ordering patterns, diagnostic performance, and costs using data from a large U.S. reference laboratory. More than 200,000 TSH-receptor antibody and TSI orders were included in the analysis.