A 56-year-old man presents with a 2-week history of fatigue. The patient's past medical history is significant for aoic and mitral valve replacement 5 months ago. A CBC shows moderate anemia with an increased reticulocyte count. Which of the following best explains the pathogenesis of anemia in this patient?
- Features given in the question point towards Macroangiopathic hemolytic anemia; most commonly results from direct red cell trauma d/t abnormal vascular surface (e.g., prosthetic hea valve) - Red cell fragmentation syndromes: Disorders in which erythrocytes are subjected to mechanical disruption as they circulate in the blood (intravascular hemolysis). Classified as macroangiopathic (large vessels), as in this case; microangiopathic (capillaries), according to site of hemolysis. Caused d/t alteration of endothelial surface of blood vessels or disturbances in blood flow patterns resulting in turbulence & increased shear stress.
Complement-mediated hemolysis
Decreased blood flow
Direct red cell trauma
Sludging of erythrocytes
Hemolytic Anemias: Basic concepts and classification