Renal pathology in paroxysmal nocturnal hemoglobinuria

The pathologic changes seen on light and electron microscopy of the kidney in paroxysmal nocturnal hemoglobinuria are described in two cases, one at autopsy and the other at biopsy. Intense hemosiderosis of the kidney is the most characteristic pathologic change in paroxysmal nocturnal hemoglobinuria although not specific for this disease. There is no apparent structural or functional reaction to the hemosiderosis. The intensity of ferritin accumulation at various points in the nephron is correlated with current concepts of hemoglobinuria, hemoglobin and ferritin metabolism and large molecule transport.