Prevalence and clinical features of hypoadrenocorticism in Great Pyrenees dogs in a referred population: 11 cases.

Naturally occurring hypoadrenocorticism (Addison's disease) is uncommon, with an estimated prevalence in the canine population between 0.06% and 0.28%. This retrospective study evaluated the prevalence and clinical features of hypoadrenocorticism in Great Pyrenees (GP) dogs presented to the Centre Hospitalier Universitaire Vétérinaire of the University of Montreal between March 2005 and October 2014. During this period, 100 dogs were diagnosed with hypoadrenocorticism, representing 0.38% [95% confidence interval (CI): 0.26% to 0.5%] of the canine population studied. The highest prevalence was observed in GP (9.73%, 95% CI: 9.12% to 10.35%, P < 0.0001), followed by West Highland white terriers (4.66%, 95% CI: 4.24% to 5.09%, P < 0.0001), Great Danes (1.87%, 95% CI: 1.6% to 2.14%, P < 0.0001), standard poodles (1.76%, 95% CI: 1.5% to 2.02%, P = 0.0001), Saint Bernards (1.72%, 95% CI: 1.47% to 1.98%, P = 0.018), and Jack Russell terriers (1.48%, 95% CI: 1.24% to 1.72%, P = 0.003). Although most clinical features were nonspecific, Great Pyrenees dogs were more frequently presented with anemia, azotemia, and eosinophilia, or with hypotension and cachexia compared with dogs of other breeds.