Concurrent hypercortisolism and hypermineralocorticoidism.

Hypertension and hypokalemia occur in patients with Cushing's syndrome whereas aldosterone production is normal and plasma renin activity is usually normal or increased. A normal aldosterone level in the face of suppressed plasma renin activity is unusual and suggests excess mineralocorticoid hormone activity. Our patient, who had Cushing's syndrome due to adrenocortical adenoma, can be classified as having low renin hypertension (suppressed renin and normal aldosterone levels). The mineralocorticoid hormone in excess was deoxycorticosterone which suppressed renin. The aldosterone production was normal and was produced solely by the adenoma. Contralateral adrenal gland suppression of both the zona glomerulosa by deoxycorticosterone via renin, and of the fasciculata by cortisol via ACTH was demonstrated after removal of the adenoma. Normal adrenal function was gradually restored.