DIABETIC REMISSION CASE REPORT IN A DOG WITH PITUITARY-DEPENDENTHYPERCORTISOLISM TREATED WITH TRILOSTANE
R Barrel1, LM Fleeman1, SJ Lim2
1 Animal Diabetes Australia, Melbourne, Australia; 2 Melbourne Veterinary School, Faculty of Science, The University of Melbourne, Werribee, Australia
Abstract: A diagnosis of diabetes mellitus, the severity of hyperglycaemia, and insulin requirement depend on the interplay between insulin resistance and residual beta cellfunction. Diabetic remission can occur in individuals with residual beta cell function when insulin resistance decreases and hyperglycaemia resolves. The mechanisms are not well understood. Diabetic remission is reported in bitches aMer dioestrus but is exceedingly rare following resolution of other insulin-resistant conditions in dogs. An 8-year-old, desexed female, Maltese-Bichon Frise crossbred dog presented with prolonged and severe signs of pituitary-dependent hypercortisolism (PDH) and a subsequent diagnosis of diabetes mellitus.
Hyperglycaemia was managed with basal-bolus insulin: glargine U300 and 30%/70% mix of regular and NPH insulins. Trilostane treatment was changed to aim for right control of hypercortisolism. Insulin treatment was discontinued 20 weeks aMer the changes. Diabetic remission met the ALIVE criteria: repeated negative glucosuria and no clinical signs four weeks aMer cessation of exogenous insulin. Euglycaemia was documented at death three weeks later. Post-mortem examination identified residual pancreatic islet cells confirmed with immunohistochemistry.
Relevance and Novel Information: This is the first report of diabetic remission in a dog with trilostane treated PDH. It provides novel insight into the relationship between insulin resistance and beta cell function. Key features: 1-hypercortisolism was severe and prolonged, indicative of insulin resistance, 2-trilostane treatment aimed for tight control, 3-insulin treatment aimed for good glycaemic control. Therefore, there might be greater likelihood of diabetic remission if: 1-there is severe and/or prolonged insulin resistance, 2-insulin resistance is substantially reduced, and 3-hyperglycaemia is controlled.
