First proof of association between autoimmune polyglandular syndrome and multiple endocrine neoplasia in humans.

Autoimmune Addison's disease (AAD) is a rare condition occurring either in isolation or associated with other autoimmune diseases as part of an autoimmune polyglandular syndrome (APS) type 1, 2 or 4. Multiple endocrine neoplasia (MEN) type 1, 2 or 4 is a hereditary autosomal dominant cancer syndrome. Medullary thyroid carcinoma and pheochromocytoma are neoplasms common to MEN-2a and MEN-2b. We describe a unique, complex case of a man resulted affected by both APS-2 and MEN-2a. The patient developed Hashimoto's thyroiditis, diabetes mellitus type 1 and AAD, despite testing negative for adrenal cortex autoantibodies (ACA) and steroid 21-hydroxylase autoantibodies (21-OHAb). Moreover, he had also a family history for MEN-2a and he first developed medullay thyroid cancer, then bilateral pheochromocytoma on the adrenal substrate of an AAD. On adrenal histology we found complete bilateral cortical atrophy in the presence of a lymphocytic infiltration and fibrosis, confirming an ACA and 21-OHAb-negative AAD. This datum is the first documented in a living individual and confirms that the absence of autoantibodies is not incompatible with an autoimmune disease and confirms that AAD is a cell-mediated autoimmune disease limited to the adrenal cortex and sparing medullary. In the light of a literature review concerning the association between APS and MEN, this is the first proven case to be reported in humans. Finally, our findings suggest that adrenal medullary tumor can develop even on an adrenal gland with cortical atrophy due to autoimmune adrenalitis.