title: Erythropoietin therapy in pre-dialysis patients with chronic renal failure: lack of need for parenteral iron.
abstract: BACKGROUND
  During erythropoietin therapy, scant information exists regarding the optimal target percent saturation of transferrin (TSAT), ferritin and the mode and amount of iron supplementation in pre-dialysis patients with anemia due to chronic kidney disease (CKD).
  
  
  OBJECTIVE
  Pre-dialysis CKD patients may have different needs for iron supplementation than end-stage renal disease subjects during erythropoietin therapy.
  
  
  METHODS
  Retrospective analysis of pre-dialysis CKD subjects (n = 31) treated with erythropoietin at our institution.
  
  
  RESULTS
  In this population our results showed that target hematocrit (33-36%) was achievable with erythropoietin (mean subcutaneous dose 86 +/- 17 [SD] units/kg/week) without parenteral iron therapy. The hematocrit increased from a mean baseline value of 28.4 +/- 2.7 to 33.6 +/- 3.4% at time 1 (4-9 weeks, p < 0.0001), and to 37.7 +/- 4.5% at time 2 (10-20 weeks, p < 0.0001). The hemoglobin concentration increased from 9 +/- 0.9 g/dl at baseline to 10.7 +/- 1.1 g/dl at time 1 (p < 0.0001) and to 12 +/- 1.5 g/dl at time 2 (p < 0.0001). Subgroup analyses of patients prescribed <200 mg oral elemental iron per day (n = 10), those with TSAT <20% and/or ferritin <100 ng/ml (n = 19), and those prescribed erythropoietin <80 units/kg/week (n = 12), all showed a significant increase in hematocrit and hemoglobin.
  
  
  CONCLUSIONS
  Our data show that pre-dialysis CKD subjects respond adequately to erythropoietin at or lower than recommended erythropoietin doses without parenteral iron. This response extends even to subgroups with TSAT and/or ferritin levels deemed to indicate iron deficiency in CKD subjects, and may be due to lack of existence of functional iron deficiency in this group of patients.
authors.affiliation: Nephrology Section, Harry S. Truman Memorial Veterans' Hospital, University of Missouri-Columbia, 800 Hospital Drive, Columbia, MO 65201, USA. trivedih@health.missouri.edu
authors.forename: Hariprasad S
authors.initials: HS
authors.lastname: Trivedi
authors.forename: Blake J
authors.initials: BJ
authors.lastname: Brooks
mesh_terms: D000368:Aged; D018798:Anemia, Iron-Deficiency / Q000097:blood / Q000188:drug therapy* / Q000209:etiology; D004305:Dose-Response Relationship, Drug; D004921:Erythropoietin / Q000008:administration & dosage*; D005260:Female; D005293:Ferritins / Q000032:analysis; D005296:Ferrous Compounds / Q000008:administration & dosage; D006400:Hematocrit; D006454:Hemoglobins / Q000032:analysis; D006801:Humans; D007676:Kidney Failure, Chronic / Q000097:blood / Q000150:complications / Q000628:therapy*; D008297:Male; D011994:Recombinant Proteins; D012016:Reference Values; D006435:Renal Dialysis; D012189:Retrospective Studies; D013997:Time Factors; D014168:Transferrin / Q000378:metabolism
chemical_list: D005296:Ferrous Compounds; D006454:Hemoglobins; D011994:Recombinant Proteins; D014168:Transferrin; D004921:Erythropoietin; C020748:ferrous sulfate; D005293:Ferritins