Intravascular Hemolysis and Acute Renal Failure After Mitral and Aortic Valve Repair  Beatrice Concepcion, MD, Stephen M. Korbet, MD, Melvin M. Schwartz, MD  American Journal of Kidney Diseases  Volume 52, Issue 5, Pages 1010-1015 (November 2008) DOI: 10.1053/j.ajkd.2008.03.021 Copyright © 2008 National Kidney Foundation, Inc. Terms and Conditions

Figure 1 Glomerular architecture is normal, with thin delicate basement membranes, patent capillaries, and normal mesangial matrix and cellularity. Note that the adjacent proximal tubules contain numerous granules of hemosiderin (periodic acid–Schiff stain; original magnification ×164). American Journal of Kidney Diseases 2008 52, 1010-1015DOI: (10.1053/j.ajkd.2008.03.021) Copyright © 2008 National Kidney Foundation, Inc. Terms and Conditions

Figure 2 Proximal tubules show widespread evidence of acute tubular necrosis, including thinning of the epithelium, loss of brush border, sloughing of cellular debris into the lumen, and mitotic figures. Note the granules of hemosiderin diffusely present in the tubular cytoplasm (periodic acid–Schiff stain; original magnification ×330). American Journal of Kidney Diseases 2008 52, 1010-1015DOI: (10.1053/j.ajkd.2008.03.021) Copyright © 2008 National Kidney Foundation, Inc. Terms and Conditions

Figure 3 Hemosiderin-laden tubular epithelium stained with Prussian blue stain (original magnification ×330). American Journal of Kidney Diseases 2008 52, 1010-1015DOI: (10.1053/j.ajkd.2008.03.021) Copyright © 2008 National Kidney Foundation, Inc. Terms and Conditions

Figure 4 Urine cytological examination shows degenerating tubular epithelial cells containing copious granules of hemosiderin (Papanicolaou stain; original magnification ×330). American Journal of Kidney Diseases 2008 52, 1010-1015DOI: (10.1053/j.ajkd.2008.03.021) Copyright © 2008 National Kidney Foundation, Inc. Terms and Conditions