SUN-316 Rare Neuroendocrine Tumor Presenting with Nocturnal Seizures

We describe an unusual case of a 55-year old female with a proinsulin secreting pancreatic endocrine adenoma. She presented with partial seizures, fasting hypoglycemia, and hypoglycemia unawareness. CT and MRI confirmed a hyper-enhancing lesion in the pancreatic body. She was effectively treated with prednisone and utilized a continuous glucose monitor (CGM) to identify and treat hypoglycemia while she awaited surgery. She underwent resection and the surgical specimen was neuroendocrine adenomatous tissue. This case has several important teaching points: [1] Fasting hypoglycemia requires a complete work up since proinsulinomas, although rare, can occur. [2] Whipple’s triad is not 100% sensitive in the work-up of hypoglycemia. Patients with persistent hypoglycemia may develop hypoglycemia unawareness. [3] Continuous glucose monitors (CGM) may provide an alternative or adjunct to standard medical therapy while patients await definitive surgery. Prednisone may also be an inexpensive and effective therapy. References1. Fadini GP MAVAea. Hypoglycemic Syndrome in a Patient with Proinsulin-Only Secreting Pancreatic Adenoma (Proinsulinoma). Case Reports in Medicine. 2011.2. Clark G, Sadur C, Puligandla B. Multiple proinsulin-secreting tumors of the pancreas treated by laparoscopic distal pancreatectomy and splenectomy. World Journal of Surgery. 2009;33(3):397-3993. F. J. Gomez-Perez DCRPAVCAASRMaJAR. Beta-cell adenomas without hyperinsulinemia with use of highly specific insulin radioimmunoassays: case report and review of literature. Endocrine Practice. 2010;16(4):660-663.4. Gury H, Rio F, Neamtu D, Boivin S. Insulinoma with hyperproinsulinemia: A two cases report. Annales d'Endocrinologie. 2002;63(3):240-242.5. Piovesan A, Pia A, Visconti G, al e. Proinsulin-secreting neuroendocrine tumor of the pancreas. Journal of Endocrinological Investigation. 2003;26(8):758-761.