Endocrine causes of hypertension.

Hypertension is a prominent feature of various endocrine diseases including primary aldosteronism, pheochromocytoma (considered separately in this issue), Cushing's syndrome, adrenal enzymatic deficiencies like 11 beta-hydroxylase, 17 alpha-hydroxylase deficiencies, and congenital or acquired 11 beta-hydroxysteroid dehydrogenase deficiencies. Patients with 11 beta-hydroxylase deficiency cannot convert 11-deoxycortisol or deoxycorticosterone into the active glucocorticoids cortisol and corticosterone, respectively. The increase in the powerful mineralocorticoid deoxycorticosterone, resulting from the enzymatic block, promotes sodium retention, hypertension, and hypokalemia. Females who have the deficiency also show signs of virilization due to the shunting of the precursors to the synthesis of adrenal androgens. Patients with 17 alpha-hydroxylase deficiency present with hypertension and/or hypokalemia, and male members exhibit pseudohermaphroditism with no development of male sexual characteristics. The defect is due to the lack of 17-hydroxylated steroids, which are necessary precursors in the synthesis of androgens and estrogens. The hypertension is due to the accumulation of the mineralocorticoid deoxycorticosterone. The mineralocorticoid receptor derives its specificity from the co-expression of the 11 beta-hydroxysteroid dehydrogenase, which converts the active steroids corticosterone and cortisol to the inactive 11-dehydrocorticosterone and cortisone, preventing their interaction with the receptor. Congenital absence of the 11 beta-hydroxysteroid dehydrogenase or acquired deficiency induced by consuming licorice or its derivatives result in occupancy of the mineralocorticoid receptor by cortisol and corticosterone, and production of mineralocorticoid-type hypertension.