Autoimmune polyendocrine syndromes

Abstract Autoimmune polyendocrine syndromes (APS), also called polyglandular autoimmune syndromes (PGAS), are a heterogeneous group of rare diseases characterized by autoimmune activity against more than one endocrine organs, although non-endocrine organs can be affected. The two major autoimmune polyendocrine syndromes, (type1–type2/APS-1 and APS-2), both have Addison's disease as a prominent component. Further autoimmune polyendocrine syndromes include APS3 and APS4. The major autoimmune polyendocrine syndromes have a strong genetic component with the type 2 syndrome occurring in multiple generations and the type I syndrome in siblings. It is well recognized that more than 20 years may elapse between the onset on one endocrinopathy and the diagnosis of the next, for example, almost 40–50% of subjects with Addison's disease will develop an associated endocrinopathy. The discovery of the polyendocrine autoimmune syndromes offered the possibility to understand autoimmune disorders with particular interest for type 1A diabetes and the neuroendocrine immunology (NEI) is further contributing to understand the links.