Successful management of nesidioblastosis in a dog with persistent hyperinsulinemic hypoglycemia following staged bilateral partial pancreatectomies.

Nesidioblastosis is a rare but important differential diagnosis for hyperinsulinemic hypoglycemia in dogs, a condition most commonly associated with insulinoma. A nine-year-old spayed female dog was presented with recurrent episodes of collapse and documented hyperinsulinemic hypoglycemia. Diagnostic imaging failed to identify a pancreatic mass, prompting exploratory laparotomy with left partial pancreatectomy and regional lymphadenectomy. Histopathological examination excluded insulinoma and established a diagnosis of nesidioblastosis. Although clinical signs initially resolved following surgery, hypoglycemia recurred 45 days later, prompting a right partial pancreatectomy. Following the second procedure, the patient remained euglycemic and free of clinical signs, without evidence of clinical diabetes mellitus or exocrine pancreatic insufficiency throughout an eight-month follow-up period. This case underscores the importance of considering nesidioblastosis in dogs with hyperinsulinemic hypoglycemia when a pancreatic mass is not identified. Furthermore, this case suggests that recurrence after unilateral partial pancreatectomy may occur because of the diffuse nature of nesidioblastosis. In this patient, staged bilateral partial pancreatectomy was associated with sustained glycemic control and clinical remission, without clinically apparent endocrine or exocrine pancreatic dysfunction during an eight-month follow-up period.