August 17, 2017
Renal hemosiderosis is a rare etiology of kidney injury that occurs secondary to diseases with chronic intravascular hemolysis. The most common associated conditions include paroxysmal nocturnal hemoglobinuria, sickle cell anemia, and the presence of a mechanical heart valve. It results from free hemoglobin being filtered by the glomeruli and reabsorbed by the proximal tubules. H&E and PAS sections show proximal tubules with cytoplasmic golden yellow to brown, granular pigment. These granules stain blue on a Prussian blue iron stain.