[Relation between autoimmune thyroid diseases and connective tissue diseases]

The main physiological function of the immune system consists in the defense against infectious micro-organisms. Sometimes there is a loss of immunological tolerance with the consequence of ignorance of self-antibodies. Some thyroid diseases are related to autoimmune diseases associated with the most common exocrine glands between them. There are also the autoimmune thyroid organ specific diseases, such as Graves-Basedow and the Hashimoto thyroiditis. It has been shown that there is a higher prevalence of autoimmune thyroid diseases in patients with connective tissue diseases (systemic autoimmune) such as Sjögren syndrome, rheumatoid arthritis, systemic lupus erithmatosis and systemic myopathic diseases. In the same way a higher prevalence of antinuclear antibodies against antigens extracted from the nucleus in patients with a thyroid autoimmune disease has been identified. There is a high percentage of patients with subclinical thyroid diseases, and it is recommended for patients with connective tissue diseases with hypo- or hyperthyroidism to have thyroid globulin and peroxide antibodies measured.