Coexistence of aldosteronoma and contralateral nonfunctioning adrenal adenoma in primary aldosteronism

A case of primary aldosteronism is presented in which computed tomography showed bilateral adrenal tumors. Adrenal scintigraphy during dexamethasone suppression revealed bilateral radiotracer uptake, with markedly predominant visualization of the left side. The left adrenal gland was removed, and an aldosterone-producing adenoma was confirmed by histologic examination. Fifteen months after surgery, serum potassium and plasma aldosterone were normal, and a marked decrease of blood pressure was observed, indicating that the right adrenal tumor was a benign nonfunctioning mass. Unilateral adrenalectomy on the side of the scintigraphically predominant lesion reversed the clinical syndrome of primary aldosteronism.