Autoimmune Polyendocrine Syndrome Type 2 (APS2)

Polyglandular autoimmune syndrome type 2 (APS-2) is an autoimmune disorder inherited through multiple genes. It is also referred to as Carpenter syndrome or Schmidt syndrome. Various endocrine diseases in a single patient were observed before the identification of APS syndrome. In 1926, Schmidt reported two cases of chronic lymphocytic thyroiditis and Addison disease, later known as Schmidt syndrome. Later on, in 1931, Snell and Rowntree documented the first case of Addison disease, who also had hyperthyroidism and type 1 diabetes mellitus (T1DM). Beaven et al. have also reviewed 66 cases, while Solomon et al. examined 113 cases of Addison disease and diabetes mellitus. The postmortem studies revealed that most of these patients had lymphocytic infiltration in their glands, proving it was an autoimmune disease. Carpenter reviewed 142 cases of Schmidt syndrome and confirmed the connection between TIDM, autoimmune thyroid disease, and Addison disease, naming it Carpenter syndrome (Anderson et al. 1980; Betterle et al. 2002; Betterle et al. 2004).