Type 2 Diabetes Mellitus in a Binturong (Arctictis binturong): A Case Report of Pancreatic Islet Amyloidosis

Type 2 diabetes mellitus (T2D) is a well-studied condition characterized by increased insulin resistance, β-cell dysfunction and amyloid deposition in the pancreatic islets. The condition is best understood in humans and veterinary species such as the domestic cat but is poorly described in zoo animals. A 16-year-old male binturong (Arctictis binturong) at Mandai Wildlife Reserve presenting initially for a left forelimb tremor was noted to have hyperglycemia (23.86 mmol/L; RI 2.93–18.94), with concurrent glucosuria, which persisted over 2 weeks. The animal was diagnosed with diabetes mellitus based on serial biochemical and urinalysis results and ultrasonography. No pharmaceutical treatment was instituted. Over 4 years the animal developed other age-related changes and was euthanized based on a declining quality of life. Postmortem investigation including histological examination found diffuse islet amyloidosis of the pancreas, consistent with T2D as seen in other species. To the authors’ knowledge, this is the first published case report of type 2 diabetes mellitus and pancreatic amyloidosis reported in the binturong. The popularity of the species in zoological institutions and long-term implications of the disease warrant further attention. Further research may be directed toward establishing diagnostic values in binturongs, as well as options for medical management.