Acute hyperkalemia induced by hyperglycemia: hormonal mechanisms.

Two insulin-requiring diabetics with isolated hyporeninemic hypoaldosteronism cpontaneously developed hyperkalemia that was aggravated whenever blood glucose concentration rose. Acute glucose infusions raised the serum potassium concentration in these patients with combined insulin and aldosterone deficiency but lowered, or did not change, the serum potassium concentration in normal subjects and in patients with either aldosterone or insulin deficiency alone. The paradoxical hyperkalemic response to glucose in patients with combined hormonal deficiency was blunted by prior administration of desoxycorticosterone acetate and abolished by prior administration of insulin. Our studies emphasize the crucial roles played by insulin and aldosterone in regulating the serum potassium concentration in man, and the need to avoid hyperglycemia in patients with combined insulin and aldosterone deficiency.