[Thyroid antibodies and their diagnostic value]

Abstract

Using commercially available test kits, thyroid-stimulating immunoglobulin (TSIg), microsomal thryoid antibodies (MAK) und antibodies against thyroglobulin (TAK) were measured in sera of 201 patients. Over 13% inhibition of TSH-binding to TSH receptor (TSIg) was found in 18 of 25 (72%) patients with hyperthyroid Graves' disease, in 18 of 61 (30) patients with Graves' disease who have become euthyroid, in 4 of 33 (15%) patients with autoimmune thyroiditis, in one of 20 patients with hyperthyroid multinodular goitre or with iodine-induced hyperthyroidism, and in 2 of 55 patients with nontoxic goitre but in none of 7 patients with congenital hyperthyroidism. When further subdividing the patients with Graves' disease who were euthyroid, TSIg values were abnormal in 47% of the patients still under treatment and in 20% of those in remission without treatment. The simultaneous presence of MAK and TAK was most often found in patients with autoimmune thyroiditis, less frequently in patients with Graves' disease and never in patients with other thyroid disorders. MAK and TAK were only detectable in patients with Graves' disease who also had TSIg. The diagnostic, prognostic and follow-up value of the three antibodies is discussed.