Plasma Aldosterone in Terminal Renal Failure

Plasma aldosterone concentrations in 27 patients with terminal renal failure ranged from subnormal to excessively elevated values and correlated significantly with plasma renin activity and potassium levels combined (r = 0.89; P < 0.001). The aldosterone level was significantly higher in patients with uncontrollable hypertension who responded to bilateral nephrectomy (Group 3) than in normotensive patients (Group 1) or in patients with hypertension treatable by sodium-volume depletion (Group 2); overlap of values between Groups 1 or 2 and Group 3 was minimal when hyperand hypo-kalemic patients were excluded. Nephrectomy was associated with disappearance of plasma renin activity and marked decrease in aldosterone. The data indicate that in terminal renal failure plasma aldosterone is largely regulated by the complementary effects of the renin-angiotensin system and potassium, the former remaining an important factor despite severe renal damage. In normokalemic terminal renal failure, plasma aldosterone correlates well with plasma renin activity in selecting those patients who require bilateral nephrectomy for hypertension.