Insulin therapy in a dog diagnosed with a metastatic insulin‐secreting neuroendocrine tumour

Abstract

A 10‐year‐old, male, neutered Jack Russell terrier cross presented for a 24‐hour history of ataxia and collapse, progressing to generalised seizures in hospital at which a severe hypoglycaemia (2.9 mmol/L; 3.5–6.7) and hyperinsulinaemia (122 mU/L; 5–40 mU/L) were documented. Fine‐needle aspirates taken from multiple hepatic masses confirmed the diagnosis of a neuroendocrine neoplasm and probable metastatic insulinoma. Initial medical treatment consisted of intravenous dextrose 5%, glucagon continuous‐rate infusion, prednisolone, diazoxide, S‐adenosylmethionine and silybin, and toceranib phosphate. Hyperglycaemia (16.9 mmol/L; 3.5–6.7 mmol/L) was documented 157 days after commencing therapy with consistent clinical signs of diabetes mellitus. All medical treatments for insulinoma were discontinued; however, the dog's hyperglycaemia persisted. Therefore, caninsulin therapy commenced at a starting dose of 0.25 IU/kg, and was gradually increased to 0.6 IU/kg in the morning and 0.5 IU/kg in the evening. The dog was treated with insulin for 140 days, before relapsing hypoglycaemia and hyperinsulinaemia, with subsequent euthanasia 320 days after the initial diagnosis.