HYPERADRENOCORTICISM ASSOCIATED WITH ADRENOCORTICAL TUMOR OR NODULAR HYPERPLASIA OF THE ADRENAL-GLAND IN FERRETS - 50 CASES (1987-1991)

Adrenocortical adenoma, nodular hyperplasia, or carcinoma was diagnose d in 50 ferrets. Thirty-five (70%) ferrets were female and 15 (30%) we re male. The mean age at which clinical signs were first noticed was 3 .4 years (range, 1 to 7 years). Clinical signs included large vulva (n = 31; 89% of females), alopecia (n = 43; 86%), pruritus (n = 20; 40%) , and increased consumption of water and increased urine output (n = 4 ; 8%). A mass was palpated at the cranial pole of the kidney during ph ysical examination of 17 (34%) ferrets. Ultrasonography, performed on 39 of 50 ferrets, revealed a unilateral adrenal gland mass in 19 (49%) . Four ferrets were anemic, and 2 ferrets were thrombocytopenic. Basel ine plasma concentrations of cortisol and corticosterone were within o r below the reference range in all 17 ferrets tested, whereas baseline plasma estradiol concentrations were high in 4 of the 11 ferrets (36% ) tested. After adrenocorticotropic hormone (ACTH) administration, onl y 1 ferret had a slightly exaggerated response on the basis of plasma cortisol concentrations, and all 17 had normal responses on the basis of plasma corticosterone concentrations. There was little or no increa se in plasma estradiol concentrations after ACTH administration. Of th e 50 ferrets, 39 were treated by adrenalectomy. Unilateral adrenalecto my was performed in 34 ferrets in which 1 adrenal gland was large, whe reas subtotal bilateral adrenalectomy was performed in 5 ferrets wi th bilateral adrenal disease. Five ferrets died in the immediate postope rative period, and follow-up information was available for the remaini ng 34, 1 to 34 months after surgery. A decrease in vulvar size was gen erally noticed by 2 days after surgery, and complete hair regrowth was noticed by 2 months.