Symposium 16: Associated autoimmune endocrine diseases

Type 1 diabetes (T1D) is associated with other autoimmune diseases frequently. Autoimmune polyendocrine syndromes (APS) comprise several entities characterized by the functional disorder of different endocrine glands caused by loss of immune tolerance. They can include non-endocrine conditions such as alopecia, celiac disease and autoimmune gastritis. These syndromes include APS type II, III, and IV. All are characterized by insidious presentation, circulating autoantibodies, and lymphocytic infiltration. The frequency and patterns of autoimmunity are highly variable and the risk of developing the diseases depends on genetic susceptibility and environmental factors. Type II is characterized by presenting two of the following T1D, autoimmune thyroiditis and Addison's disease. Type III is defined by the presence of autoimmune thyroid disease and T1D without adrenal disease, and type IV is a diagnosis of exclusion with association of two or more autoimmune endocrine syndromes that do not constitute APS II or III1. Female sex and age are risk factors for the association of T1D with other autoimmune diseases2.