Adrenal gland function in a dog following unilateral complete adrenalectomy and contralateral partial adrenalectomy

Case Description-A 40.3-kg (88.7-lb) 6-year-old spayed female Labrador Retriever was evaluated because of acute unilateral epistaxis. Clinical Findings-During the initial evaluation of the dog, systemic hypertension and a left adrenal gland mass were detected. The left adrenal gland mass was surgically removed; results of histologic examination of the mass indicated it was a pheochromocytoma. Ten months later, the dog was evaluated because of persistent systemic hypertension and development of polyuria, polydipsia, and excessive panting. Abdominal ultrasonography re-vealed a mass in the cranial aspect of the right adrenal gland; results of MRI suggested the mass was a malignant tumor. Treatment and Outcome-Epistaxis resolved after treatment and resolution of severe systemic hypertension. A partial right adrenalectomy was performed to remove the right adrenal gland mass. Results of histologic examination of the mass indicated it was a well-differentiated carcinoma of the cortex of the adrenal gland. Results of ACTH stimulation tests after surgery indicated the dog had adequate adrenal gland function. Clinical Relevance-Partial adrenalectomy may be a safe and feasible treatment option to preserve adrenal gland function in dogs with small eccentrically located adrenal gland masses, particularly for dogs that have undergone removal of the contralateral adrenal gland.