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Thyroid Function Tests

by Elaine Moore

Blood Thyroid Function Tests, including levels of thyroid hormones and the pituitary hormone TSH are used to diagnose thyroid disorders. These tests are also used to monitor anti-thyroid drug therapy in GD patients and also thyroid hormone replacement therapy in patients who have become hypothyroid. Thyroid antibody tests are used to confirm GD and predict remission.

 A positive test for stimulating TSH receptor antibodies, which is also known as thyroid stimulating antibodies (TSI) confirms Graves' disease although negative results do not rule out Graves'disease. The RAI-U test is an older and less specific test used to confirm Graves' disease.

 Measurements of thyroid hormone in the blood are used to diagnose hyperthyroidism and hypothyroidism. Levels of the pituitary hormone TSH also reflect thyroid status as described in my article on laboratory tests. Positive thyroid antibody levels confirm that one has an autoimmune thyroid disorder. The RAI-U test may also be used to confirm GD, but it is not as sensitive a test.

© 7 May 2006 Copyrighted  by Elaine Moore


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Elaine Moore Graves' Disease and Autoimmune Disease Education 
Copyrighted by Elaine Moore. © All Rights Reserved 
Last updated: Oct 24, 2015

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