Renal impairment in patients with paroxysmal nocturnal hemoglobinuria

Three patients with paroxysmal nocturnal hemoglobinuria accompanied by chronic renal lesions were studied. All the cases had histories of severe hemolytic anemia and repeated hemoglobinuria. The biopsy specimen of the kidney of two patients (Case 1 and Case 2) showed interstitial nephritis. Renal glucosuria, tubular proteinuria, increased urate clearance (Case 2) and reduced tubular reabsorption of phosphate (Case 3) were revealed in Case 2 and Case 3, suggesting renal tubular impairment. From the nephrological point of view, hemodynamic alteration resulting from intravascular hemolysis and severe persistent chronic anemia may primarily be responsible for the renal impairment.