Perianal adenomas and hypertestosteronemia in a spayed bitch with pituitary-dependent hyperadrenocorticism.

Hypertestosteronemia was diagnosed in a spayed bitch with pituitary-dependent hyperadrenocorticism and perianal adenomas. Serum concentrations of cortisol and testosterone decreased after treatment with mitotane was instituted. Excessive testosterone in this dog was thought to have been produced by the adrenal cortex, possibly in response to excessive ACTH concentrations. Development of androgen- or estrogen-responsive tumors in castrated dogs may be an early indication of adrenocortical hyperfunction.