Insulinoma: An undervalued diagnosis of hypoglycemia in elderly patients

Insulinoma is a rare pancreatic endocrine tumor, characterized by the inappropriate secretion of insulin, leading to episodes of hypoglycemia. During these hypoglycemic events, patients may experience autonomic and neuroglycopenic manifestations. However, it is important to note that insulinoma can also have long-term effects on cognitive function, even after hypoglycemia resolution. We present the case of an 89-year-old female with a gradual cognitive decline two years prior and recurrent episodes of stuporous level of consciousness in the preceding months. Insulinoma was confirmed through the measurement of plasma glucose, insulin, and C-peptide levels. Following the biochemical confirmation, a computed tomography (CT) scan successfully located the tumor. Surgical resection was considered high-risk. Nevertheless, after dietary modifications and the administration of diazoxide, the patient's hypoglycemic episodes were controlled. This case report highlights the importance of considering insulinoma as a potential cause of unexplained episodes of hypoglycemia, particularly in older patients with cognitive impairment.