DOGS TREATED WITH TRILOSTANE IN FIRST OPINION PRACTICE USING A PROTOCOL FORTIGHT CONTROL OF HYPERCORTISOLISM: EFFECTIVENESS AND SAFETY

Foster SF ,

1 Fleeman LM,2 Morton JM,3 Langner KFA, 4 Braddock JA1

1. Vetnostics, 60 Waterloo Rd, Macquarie Park NSW 2113, Australia; 2. Animal Diabetes

Australia, 5 Hood St, Collingwood VIC 3066, Australia; 3. Jemora Pty Ltd, PO Box 5010, East, Geelong Vic 3219, Australia; 4. Western Australian Veterinary Emergency and Specialty, 1/640 Beeliar Drive, Success WA 6164, Australia

Background: There is no agreement about ideal control of hypercor@solism in dogs treated with trilostane.

Hypothesis: In first opinion practice, tight control of hypercortisolism, defined by adrenocor@cotropic hormone (ACTH)-stimulated cortisol concentrations <70 nmol/L (Advia Centaur) on tests performed 4-6 h after trilostane, is safe and effective.

Methods: Dogs with hypercortisolism in first opinion practice which had tight control on all tests for a minimum of 12 months (tight control period) were identified between August 2017 and February 2019. Owners completed a questionnaire rela@ng to the most recent tight control period. Signalment, clinical score, and adverse effects were recorded. For each dog’s most recent tight control period, the percentages of ACTH-s@mulated cortisol concentrations <14 nmol/L and <30 nmol/L were determined.

Results: There were 41 tight control periods in 40 dogs. Age at first monitoring test was 4-16 years (median 10 years). One-third (13/40) of cases were Maltese, Shih Tzus, or their crosses. Clinical score for the most recent tight control period was excellent in 25, reasonable in 13, and poor in 2 dogs. Percentages of post-stimulation cortisol concentrations <30 nmol/L per dog were 0-88% (median 36%) with 35% of dogs having ≥50% results <30 nmol/L. Post-stimulation cortisol concentrations were <14 nmol/L in 9/239 (4%) of tests. Adverse events were uncommon; only 5 dogs had vomiting or diarrhea more than once during the tightly controlled period.

Conclusions: This protocol of tight control in first opinion practice is generally effective and does not impact negatively on dogs’ health.