Multiple endocrine neoplasia type 1 with neuroglycopenic symptoms with a novel heterozygous MEN1 gene mutation.

Background: Multiple endocrine neoplasia type 1 (MEN1) is an autosomal dominant disorder caused by mutations in the MEN1 gene located on the long arm of chromosome 11.

Case presentation: A 32-year-old male was admitted to the Division of Endocrinology with a three-year history of recurrent episodes of altered consciousness and abnormal mental behavior. Laboratory tests and imaging studies revealed primary hyperparathyroidism (PHPT), multiple pancreatic adenomas, and a pituitary adenoma. Genetic analysis identified a heterozygous germline mutation in exon 2 of the MEN1 gene (NM_130799; c.416A > T, p.(His139Leu)), confirming a diagnosis of Multiple Endocrine Neoplasia Type 1 (MEN1).

Conclusions: MEN1 patients should be evaluated for clinical manifestations of neuroglycopenia caused by pancreatic neuroendocrine tumors (pNETs). These neuroglycopenic symptoms (altered consciousness and abnormal mental behavior) should be distinguished from the neuropsychiatric and cognitive symptoms associated with PHPT. Furthermore, our report describes the identification of the first mutation associated with MEN1 as NM_130799.2: c.416A > T, p.(His139Leu). It provides valuable insight into the clinical presentation of multiple endocrine neoplasia type 1.