Autoimmune thyroid disorders (AITD) are organ-specific autoimmune diseases-Th1 orientated. Hashimoto’s thyroiditis (HT), and Graves’ disease (GD) are the principal clinical presentations of AITD, that have been also shown in systemic rheumatologic diseases (as Sjögren’s syndrome, systemic lupus erythematosus, rheumatoid arthritis, systemic sclerosis, or cryoglobulinemia), together with thyroid autoantibodies and thyroid dysfunctions. New associations of AITD with other autoimmune diseases are being discovered, for example with psoriatic arthritis and dermatological diseases.
We have searched on Pubmed about associations of AITD with other autoimmune diseases.
Several investigations suggested the importance of a shared genetic susceptibility and of environmental factors in patients in whom a coexistence of autoimmune diseases is present. A major Th1 autoimmune response occurs in the initial, and/or active phases of organ-specific autoimmune disorders and/or systemic rheumatologic diseases with increased serum, or tissue, expressions of the Th1 chemokine CXCL10.
Thyroid disorders might have an important clinical impact, therefore patients with rheumatologic or dermatologic autoimmune diseases, overall if females and with circulating thyroid autoantibodies, need to be periodically evaluated for thyroid dysfunctions. Furthermore, drugs targeting the Th1 immune response should be evaluated in patients with AITD to prevent the appearance of other autoimmune disorders.