Recurrent Hypoglycemia in a Non-diabetic: A Case of Suspected Insulinoma Lost to Follow-Up

Insulinomas are rare insulin-secreting pancreatic neuroendocrine tumors (PNETs) that can cause profound hypoglycemia, particularly in non-diabetic patients. We report the case of a 56-year-old female who presented to the emergency department with altered mental status, a witnessed seizure, and recurrent, refractory hypoglycemia. She had no history of diabetes or hypoglycemic agent use and was reportedly in her usual state of health until the event. Initial emergency evaluation revealed persistent hypoglycemia despite dextrose administration. Cross-sectional imaging identified a pancreatic lesion concerning for insulinoma in the appropriate clinical context. Although confirmatory outpatient biochemical testing (e.g., insulin, C-peptide levels) was planned, the patient was ultimately lost to follow-up. This case underscores the critical role of emergency physicians in maintaining a broad differential when evaluating unexplained, refractory hypoglycemia, particularly when formal diagnosis is precluded.