Role of proteinuria in the anemia of chronic kidney disease.

The most important contributors to the anemia of patients with chronic kidney disease are insufficient erythropoietin production and erythropoietin hyporesponsiveness, decreased red blood cell half-life, iron deficiency, and inflammation. However, in contrast to the role of kidney failure, that of proteinuria and nephrotic syndrome is less clear. Bissinger et al. now provide evidence in mouse models and patients with chronic kidney disease that heavy proteinuria alters erythrocyte metabolism and increases erythrocyte death.