Associations of autoimmune endocrine diseases

Recently, an increasing amount of data on the connection between neuro-endocrine and immune systems has been gathered. Results of molecular genetic research have provided evidence for a common language of these systems including neurotransmitters, hormones and cytokines. It has been proved that the immune system is capable of producing neurotransmitters and hormones and even the endocrine system can prepare cytokines. This integrative (holistic) approach makes possible the investigation of physiological and pathological events as interactions of psychoneuro-endocrine-immune systems. The associations of autoimmune diseases and the autoimmune polyendocrine syndromes constitute a heterogeneous group of disorders characterised by decreased or lost immune tolerance against self-antigens. Molecular genetic research has explored the mechanism of the associations of diseases that are called organ-specific. Autoimmune polyendocrine syndrome type 1 is characterised by the presence of at least two of the three cardinal diseases: Addison's disease, autoimmune hypoparathyroidism and mucocutaneous candidiasis. This rare autosomal recessive syndrome is induced by mutations of the autoimmune regulator (AIRE) gene. Autoimmune polyendocrine syndrome type 2 that occurs at a much higher frequency is observed and defined as the coexistence of Addison's disease, autoimmune thyroid disease and/or type 1 diabetes mellitus. Autoimmune polyendocrine syndrome type 3 is characterised by an association of autoimmune thyroid disease and type 1 diabetes mellitus. In contrast to autoimmune polyendocrine syndrome type 1, HLA and other antigens have proved to be important in types 2 and 3 of the syndrome. Identification of genetic factors predisposing to these syndromes contributes to our understanding of the common mechanisms involved in autoimmunity and offers a possibility for early treatment and prevention as well.