Syndrome of Hyporeninemic Hypoaldosteronism and Hyperkalemia in Renal Disease

Abstract

Four patients presented with hyperkalemia and were found to have mild to marked chronic non-oliguric renal failure, normal diastolic blood pressure, mild hyperchloremic acidosis and impaired renal conservation of sodium during sodium restriction. The hyperkalemia was corrected by exogenous mineralocorticoids. Plasma renin activity and concentration, renin substrate, plasma aldosterone and cortisol were measured. Subnormal levels of plasma renin activity and concentration and of plasma aldosterone were found with diminished responses to upright posture, sodium restriction and exogenous catecholamines. Infusions of angiotensin or ACTH consistently caused modest increases in plasma aldosterone levels. Plasma renin substrate, plasma cortisol and urinary 17-OH-corticosteroids were normal. The data indicate that the hyperkalemia was caused by selective hypoaldosteronism secondary to failure of the renin-angiotensin system. It is postulated that possible factors contributing to this syndrome are structural or functional changes of the juxtaglomerular appartus secondary to renal disease and altered adrenal function associated with aging.