Hemoglobinuric acute kidney injury from aortic root graft malfunction

Hemolysis and consequent hemoglobinuria is a well-known cause of acute kidney injury (AKI). Hemolysis has been associated with malpositioned prosthetic valves, but other prosthetic devices may rarely be associated with red cell shear stress. We report a case of a 56-year-old man who presented with hemolysis, AKI, and anemia. During workup, he was found to have anti-phospholipid antibodies, leading to a presumptive diagnosis of catastrophic anti-phospholipid antibody syndrome. However, further investigation revealed the cause of hemolysis to be from aortic root graft dysfunction. Following replacement of the prosthesis, there was complete resolution of his hemolysis and recovery of renal function. This case underscores the need to consider cardiac prosthetic devices in patients presenting with hemoglobinuric AKI.