Adrenocorticotropin Deficiency: Correction of Hyponatremia and Hypoaldosteronism with Chronic Glucocorticoid Therapy*

A 36-yr-old woman with a chronic wasting illness associated with hyponatremia and hypotension proved to have secondary adrenal insufficiency and low levels of GH and PRL. TSH, LH, and FSH responses remained normal. Aldosterone excretion was markedly reduced (0.74 microgram/day) before replacement therapy was started, but normal renin and aldosterone responses to sodium restriction were observed after 6 months of corticosteroid treatment. These responses were maintained after acute steroid withdrawal despite the continued absence of ACTH. Chronically adequate glucocorticoid levels were necessary to maintain a normal aldosterone response in this patient. If there is also a pituitary factor required for this response, it does not appear to be ACTH.