Concurrent Type 2 Diabetes and Multiple Endocrine Neoplasia Type 1 With a Novel MEN1 Gene Mutation

Abstract

Multiple endocrine neoplasia type 1 (MEN1) is an autosomal dominant inherited disorder that is characterized by the combined occurrence of primary hyperparathyroidism (PHPT), enteropancreatic neuroendocrine tumors and anterior pituitary adenomas. Increased insulin resistance and a higher prevalence of glucose intolerance have been noted in MEN1 families and are associated with increased cardiovascular mortality. Mutations in the MEN1 tumor suppressor gene cause multiple tumors in MEN1 but can also be associated with glycemic dysregulation. A 52-year-old man was admitted for blood glucose control. He had been diagnosed with diabetes 3 years previously. Hypercalcemia was incidentally detected during a blood test. After examination, he was diagnosed with PHPT caused by parathyroid hyperplasia. On genetic analysis, he was found to have a novel mutation in the MEN1 gene (exon 10, c.1590_1606_del; p.Gly532AlafsX20). We report a case of MEN1 with a novel MEN1 gene mutation associated with type 2 diabetes in a patient with no family history of diabetes. This is the first case of MEN1 associated with type 2 diabetes before pancreatic surgery in Korea. J Med Cases. 2014;5(11):596-600 doi: http://dx.doi.org/10.14740/jmc1973w