OBJECTIVE: To present a case of recurrent hypoglycemia following Roux-en-Y gastric bypass (RYGB) surgery whose etiology was determined to be a proinsulin-predominant pancreatic neuroendocrine tumor (a proinsulinoma). METHODS: A case report along with a brief discussion and review of the pertinent literature is presented. RESULTS: The patient is a 62-year-old female who presented with symptomatic hypoglycemia 11 years after RYGB surgery. Initial workup revealed low insulin levels with elevated proinsulin levels. A 72-hour fast confirmed the presence of proinsulin-induced hypoglycemia secondary to a pancreatic neuroendocrine tumor (PNET). She underwent distal pancreatectomy with splenectomy and a PNET tumor was successfully removed with resolution of her symptoms. CONCLUSION: Hypoglycemia after RYGB surgery is a well-established syndrome. While there are several etiologies for this, PNETs (including proinsulinomas) should be considered in the differential diagnosis in this population. Proinsulinomas are an increasingly recognized cause of hypoglycemia. Proinsulin levels must always be included as part of the workup of hypoglycemia in an adult.
OBJECTIVE: To present a case of recurrent hypoglycemia following Roux-en-Y gastric bypass (RYGB) surgery whose etiology was determined to be a proinsulin-predominant pancreatic neuroendocrine tumor (a proinsulinoma). METHODS: A case report along with a brief discussion and review of the pertinent literature is presented. RESULTS: The patient is a 62-year-old female who presented with symptomatic hypoglycemia 11 years after RYGB surgery. Initial workup revealed low insulin levels with elevated proinsulin levels. A 72-hour fast confirmed the presence of proinsulin-induced hypoglycemia secondary to a pancreatic neuroendocrine tumor (PNET). She underwent distal pancreatectomy with splenectomy and a PNET tumor was successfully removed with resolution of her symptoms. CONCLUSION: Hypoglycemia after RYGB surgery is a well-established syndrome. While there are several etiologies for this, PNETs (including proinsulinomas) should be considered in the differential diagnosis in this population. Proinsulinomas are an increasingly recognized cause of hypoglycemia. Proinsulin levels must always be included as part of the workup of hypoglycemia in an adult.
Authors: Geoffrey J Service; Geoffrey B Thompson; F John Service; James C Andrews; Maria L Collazo-Clavell; Ricardo V Lloyd Journal: N Engl J Med Date: 2005-07-21 Impact factor: 91.245
Authors: James C Yao; Manal Hassan; Alexandria Phan; Cecile Dagohoy; Colleen Leary; Jeannette E Mares; Eddie K Abdalla; Jason B Fleming; Jean-Nicolas Vauthey; Asif Rashid; Douglas B Evans Journal: J Clin Oncol Date: 2008-06-20 Impact factor: 44.544
Authors: Gian Paolo Fadini; Alberto Maran; Anna Valerio; Francesco Meduri; Mariarosa Pelizzo; Diego Miotto; Cristiano Lanza; Giuseppe Altavilla; Angelo Avogaro Journal: Case Rep Med Date: 2011-07-03