Resolution of hyperinsulinemic hypoglycemia following partial pancreatectomy in a dog with nesidioblastosis

Abstract

CASE DESCRIPTION A 6-year-old castrated male Australian Shepherd was evaluated because of a recent onset of persistent hypoglycemia. CLINICAL FINDINGS Physical examination results were generally unremarkable. No abnormalities were detected on thoracic radiographs, and abdominal ultrasonography revealed no obvious pancreatic lesion. Hematologic analysis revealed hypoglycemia with a high serum insulin-to-glucose concentration ratio. TREATMENT AND OUTCOME Insulinoma was suspected; medical treatment with prednisone was initiated, and exploratory laparotomy was performed. No pancreatic lesions or masses were observed. Partial left pancreatectomy and hepatic and local lymph node biopsies were performed. Histologic examination revealed islet cell hypertrophy and hyperplasia, with no evidence of neoplasia. Results of a PCR assay of the pancreatic tissue for Bartonella infection were negative. Clinical, biochemical, and histopathologic findings were compatible with nesidioblastosis. The clinical signs, including hypoglycemia, resolved after surgery. On follow-up examination 8 months later, the dog was apparently healthy and results of a CBC and serum biochemical analysis, including blood glucose concentration, were within respective reference ranges. CLINICAL RELEVANCE To our knowledge, this is the first report of nesidioblastosis in a dog for which clinical signs and clinicopathologic abnormalities resolved after partial pancreatectomy. Although extremely rare, nesidioblastosis should be considered a differential diagnosis in dogs with signs suggestive of insulinoma.

Suspected congenital hyperinsulinism in a Shiba Inu dog

“…Despite a positive response to diazoxide treatment, insufficient evidence was available to confirm an etiology in our case. Two cases termed nesidioblastosis have been reported in the veterinary literature (a 6‐year‐old cat and a 6‐year‐old dog) 19,20 . In these cases, adult‐onset hypoglycemia resolved with partial pancreatectomy in a dog, and pancreatic histopathology disclosed diffusely increased islet area in the pancreas without evidence of malignancy and multifocal micronodular hyperplasia of endocrine and exocrine tissue in a cat.…”

Diffuse, Adult-Onset Nesidioblastosis/Non-Insulinoma Pancreatogenous Hypoglycemia Syndrome (NIPHS): Review of the Literature of a Rare Cause of Hyperinsulinemic Hypoglycemia

“…Of interest, nesidioblastosis with or without hyperinsulinemic hypoglycemia was reported in animals. Cases of a 2-day-old Simmental calf (no hyperinsulinism) [ 365 ], young Beagle dogs (no hyperinsulinism) [ 366 ], a 6-year-old castrated male Australian Shepherd (hyperinsulinemic hypoglycemia) [ 367 ], old dogs (some with hypoglycemia and/or hyperinsulinism) [ 368 ], two squirrel monkeys (hyperglycemia with glucagon-reactive nesidioblastosis) [ 369 ], a cat (hyperinsulinemic hypoglycemia) [ 370 ], and several aged horses (no documented hyperinsulinism) [ 371 ] were found in the literature. If the pathophysiology and etiology of these morphological findings are similar to the ones in humans remains to be established.…”

Current Trends in Diagnosis, Treatment and Prognosis of Canine Insulinoma

“…Less common differential diagnoses are juvenile hypoglycaemia, hunting dog hypoglycaemia, glycogen storage disease, glucagon deficiency and nesidioblastosis. Finally, the iatrogenic causes of hypoglycaemia include the administration of drugs like insulin and sulfonylurea [ 5 , 29 , 32 ]. Differential diagnoses of canine insulinoma can be excluded by simultaneously measuring their insulin levels at the time when the hypoglycaemia is diagnosed.…”