Laboratory tests are essential for the diagnosis and follow-up of autoimmune and neoplastic thyroid diseases. The most important test for the etiologic diagnosis of Hashimoto's thyroiditis, a disease with high prevalence in the population, is the determination of anti-thyroperoxidase antibodies (A-TPO), which is also useful for the diagnosis of Graves' disease, for predicting risk of hypothyroidism in sub-clinical hypothyroidism and for predicting postpartum thyroiditis in at-risk women. Another very useful test in autoimmune diseases is the determination of anti-TSH receptor antibodies (TRAb) in the diagnosis of rare forms of Graves' disease, as patients with few symptoms or multi-nodular goiters. In thyroid cancer, thyroglobulin is essential in the follow-up of patients with differentiated thyroid cancer (papillary and follicular), whereas calcitonin is necessary for the diagnosis and follow-up of medullary thyroid carcinoma.
Anti-thyroperoxidase antibodies; Anti-TSH receptor antibodies; Thyroglobulin; Calcitonin
