This anti-thyroglobulin (anti-Tg) is an auto antibody to thyroid thyroglobulin, and is a confirmation test for a diagnosis of Hashimoto's thyroiditis.  Antibody is present in significant titers in Hashimoto's thyroiditis and Grave's disease. Anti-thyroglobulin (anti-Tg) can also be present with any process causing active chronic destruction of follicles, even such as diffuse sclerosing variant of papillary thyroid cancer. Elevated levels of this antibody may cause problems in tests to determine a patient's serum thyroglobulin level.

References:

1. thyroid tests Practice Guidelines, National Academy of Clinical Biochemistry (NACB), USA.

(posted 2005; latest update 23 October 2007)