The pancreas in idiopathic Addison's disease--a search for a prediabetic pancreas

Autopsy pancreases were studied from 14 patients who had idiopathic Addison's disease. One patient had been diabetic for 12 years and three patients were found to be diabetic during their terminal admission. While there was no evidence of diabetes or destruction of insulin-secreting beta cells in the remaining 10 patients, islets in one pancreas exhibited many of the histological and immunohistochemical features seen in the patients with recent onset diabetes. These included the presence of alpha-interferon in endocrine cells, hyper-expression of class I major histocompatibility complex molecules by endocrine cells in islets where alpha-interferon was also present, aberrant expression of class II major histocompatibility complex molecules by endocrine cells and the presence of insulitis. Since the combination of these changes has only been described in type 1 diabetes it is thought that the appearances seen in this pancreas were those of prediabetes.