Iron deficiency in patients with chronic kidney disease: potential role for intravenous iron therapy independent of erythropoietin

The prevalence of iron deficiency and its contribution to the anemia of end stage renal disease has been extensively studied, but much less is known about the role of iron deficiency in the pathogenesis of the anemia of chronic kidney disease in predialysis patients. All new hemodialysis patients entering a single hemodialysis unit between July 1999 and April 2002 were included in the study. The admission laboratory tests and the Health Care Financing Administration (HCFA) 2728 form were examined to determine the prevalence of erythropoietin use, anemia (Hb < 11 g/dl), and iron deficiency (ferritin < 100 ng/ml and transferrin saturation % < 20%). In a second part of the study, the effect of intravenous iron gluconate replacement in patients with stage III & IV chronic kidney disease was examined. Anemia was present in 68% of all patients starting hemodialysis. Iron deficiency was a common feature occurring in 29% of patients taking erythropoietin (49% of all patients) and 26% of patients without erythropoietin (51 % of all patients). Following the administration of intravenous iron gluconate to four patients, there was a significant rise in hemoglobin levels from 10.6 +/- 0.19 to 11.7 +/- g/dl (p=0.02). Conclusion: Iron deficiency is common in predialysis patients. Replenishing iron stores in anemic patients with chronic kidney disease significantly increases hemoglobin levels and should be considered as an integral part of the therapy for treating anemia in the predialysis population.