Post–Gastric Bypass Hypoglycemia in a Patient with End-Stage Renal Disease

ABSTRACT Objective: To highlight an atypical presentation of post–gastric bypass hypoglycemia complicated by end-stage renal disease (ESRD). Methods: A case report of relevant medical history, in addition to diagnostic and treatment challenges are presented. Results: We describe a 42-year-old female who presented for syncope due to hypoglycemia. She had a history of ESRD on dialysis as well as Roux-en-Y gastric bypass (RYGB) 10 years prior to admission. Diagnostic evaluation, although confounded by renal failure, favored insulin-mediated hypoglycemia and selective arterial calcium stimulation testing suggested noninsulinoma pancreatogenous hypoglycemia syndrome (NIPHS). Failure of multiple medical therapies ultimately led to partial pancreatic resection, with pathology confirming the diagnosis, and clinical improvement. Conclusion: Although hypoglycemia after gastric bypass is a well-recognized disorder, the pathophysiology and best treatment plan is still under investigation. Our case report of surgical pathology-proven NIPHS is the first in a patient with ESRD and a history of RYGB. Diagnosis of hypoglycemic disorders in patients with concomitant renal failure is quite challenging and highlights the important role of the kidney in glucose homeostasis. Abbreviations: ESRD end-stage renal disease; NIPHS noninsulinoma pancreatogenous hypoglycemia syndrome; RYGB Roux-en-Y gastric bypass