Diabetes mellitus and hyperkalemic renal tubular acidosis: case reports and literature review

Hyporeninemic hypoaldosteronism, despite being common, remains an underdiagnosed entity that is more prevalent in patients with diabetes mellitus. It presents with asymptomatic hyperkalemia along with hyperchloraemic metabolic acidosis without significant renal function impairment. The underlying pathophysiological mechanism is not fully understood, but it is postulated that either aldosterone deficiency (hyporeninemic hypoaldosteronism) and/or target organ aldosterone resistance (pseudohypoaldosteronism) may be responsible. Diagnosis is based on laboratory parameters. Treatment strategy varies according to the underlying pathophysiological mechanism and etiology and aims to normalize serum potassium. Two clínical cases are reported and the relevant literature is revisited.