Unilateral adrenal catecholamine excess. Pheochromocytoma or possible sporadic medullary hyperplasia.

A 60-year-old man had clinical and biochemical evidence of pheochromocytoma. Venous blood from the left adrenal gland had strikingly higher concentrations of l-norepinephrine, epinephrine, and dopamine than that from the right adrenal gland. The patient's condition was cured following left adrenalectomy. Pathologic examination of the left adrenal gland did not reveal either pheochromocytoma or medullary hyperplasia but rather hemorrhagic degeneration of the medulla of an enlarged adrenal gland. Although only one adrenal gland was removed, Addison's disease developed.