Hyporeninemic hypoaldosteronism--case report and observation of dissociated renin and erythropoietin activity.

A case is reported of hyporeninemic hypoaldosteronism, diagnosed during an evaluation of hyperkalemia. Urine and plasma aldosterone concentrations were depressed despite hyperkalemia and were not responsive to ACTH, cosyntropin, and angiotensin 2. Adrenal glucocorticoid function was normal. Plasma renin activity also was low, and was hyporesponsive to stimulation, including intravascular volume contraction and potassium depletion. Autonomic nervous function was intact. Of the 32 previously reported cases of selective hypoaldosteronism, plasma renin activity was low in the majority of cases in which it was measured. A classification of the types of selective hypoaldosteronism is presented. It is of interest that the serum erythropoietin activity in this case was increased while plasma renin activity was markedly depressed.