A Rare Case of Co-occurrence of Multiple Endocrine Neoplasia Syndrome and Congenital Adrenal Hyperplasia

Multiple endocrine neoplasia type 1 (MEN1) and congenital adrenal hyperplasia (CAH) are rare monogenic hereditary endocrinopathies with a prevalence of 1–9 cases per 100,000 and 9–15 cases per 100,000, respectively. MEN1 is characterized by the development of multiple endocrine and nonendocrine organ tumors, including parathyroid, pituitary, and duodenopancreatic neuroendocrine tumors (NETs), which constitute the classical triad of the disease. CAH is associated with genetic defects in enzymes and transport proteins involved in the synthesis of adrenal cortical steroid hormones. Overall, cases of the combination of two hereditary diseases in one patient are extremely rare. In this article, we describe a clinical case of the combination of MEN-1 with all three classical components and CAH, which, taking into account the low prevalence of both diseases, represents scientific interest. To date, only one similar case has been described in the literature. In addition, the paper discusses the pathogenetically determined combination of CAH and Ehlers-Danlos syndrome, known as the CAH-X syndrome.