[Normal and pathologic endocrinology of the adrenal glands]

The adrenal glands produce glucocorticoids (approximately 25 mg cortisol/day), mineralocorticoids (approximately 100 micrograms aldosterone/day) and androgens (e.g. dehydroepiandrosterone = DHEA approximately 10 mg/day) in their cortex and catecholamines in their medulla. Excessive cortisol production leads to Cushing's syndrome. In approximately 2/3 of the cases this is due to ACTH oversecretion most often from a pituitary adenoma and can be cured by removal of this adenoma. Cushing's syndrome caused by an adrenal adenoma, carcinoma or bilateral nodular adrenal hyperplasia is treated by adrenal surgery. Nelson's syndrome consists of hyperpigmentation of the skin and an often aggressively growing pituitary adenoma which secretes excessive amounts of ACTH. Treatment is surgical. Conn's syndrome (primary hyperaldosteronism) is due to aldosterone hypersecretion most often from an adrenal adenoma (therapy: unilateral adrenalectomy), more seldom from bilaterally hyperplastic adrenals (therapy: spironolactone). Excessive adrenal androgen secretion is found in the adrenogenital syndrome in which defective cortisol biosynthesis leads to ACTH oversecretion and ACTH-stimulated overproduction of cortisol precursors, some of which are androgens. Treatment consists of glucocorticoids which suppress the ACTH oversecretion. Pheochromocytomas produce excessive amounts of catecholamines and cause hypertension which can be persistent as well as episodic. Therapy consists of adrenalectomy. Malignant tumors of the adrenals have a poor prognosis. Incidentally found adrenal masses ("incidentalomas") are observed at regular intervals if they are small and should be surgically removed if they have a tendency to grow or are large (greater than or equal to 5 cm phi).