title: Bone marrow iron, iron indices, and the response to intravenous iron in patients with non-dialysis-dependent CKD.
abstract: BACKGROUND
  Information about iron stores and their relationship with transferrin saturation (TSAT), serum ferritin, and the erythropoietic response to iron therapy is scarce in anemic non-dialysis-dependent patients with chronic kidney disease (CKD). We examined the diagnostic utility of peripheral-iron indices and the erythropoietic response to intravenous iron as indices of iron store depletion using bone marrow iron as a reference test in anemic non-dialysis-dependent patients with CKD.
  
  
  METHODS
  Diagnostic test study.
  
  
  METHODS
  100 anemic (hemoglobin <11 g/dL) patients with CKD stages 3-5, not receiving epoetin and iron.
  
  
  METHODS
  TSAT index and serum ferritin level at baseline and increase in hemoglobin level 1 month after 200 mg of iron sucrose daily for 5 days.
  
  
  METHODS
  Bone marrow iron (assessed using aspiration and Perls' stain), depleted versus replete, at baseline.
  
  
  METHODS
  Area under the receiver operating characteristic curve (AUROC), sensitivity, and specificity of peripheral-iron indices and erythropoietic response to describe bone marrow iron stores.
  
  
  RESULTS
  Bone marrow iron stores were depleted in 48% of patients at baseline. In iron-depleted versus -replete subjects, mean hemoglobin level, median TSAT index, median serum ferritin level, and hemoglobin level increase after iron sucrose administration were 8.74 +/- 1.1 (SD) versus 9.22 +/- 0.9 g/dL (P = 0.02), 19% (interquartile range [IQR], 15%) versus 28% (IQR, 12%; P < 0.001), 100 (IQR, 131) versus 220 ng/mL (IQR, 213; P < 0.001), and 1.2 +/- 0.4 versus 0.8 +/- 0.3 g/dL (P < 0.001), respectively. TSAT, ferritin level, and increase in hemoglobin level AUROCs were similar: 0.75 (95% CI, 0.66-0.85), 0.76 (95% CI, 0.66-0.85), and 0.74 (95% CI, 0.65-0.84), respectively.
  
  
  CONCLUSIONS
  Bone marrow iron as the index of iron stores.
  
  
  CONCLUSIONS
  Half the anemic patients with CKD stages 3-5 had depleted iron stores. Peripheral-iron indices and erythropoietic response had equivalent, but limited, utility in identifying depletion of bone marrow iron stores. Use of these indices to indicate depletion of iron stores should be reconsidered.
authors.affiliation: Carol Davila University of Medicine and Pharmacy, Bucharest, Romania.
authors.forename: Simona
authors.initials: S
authors.lastname: Stancu
authors.forename: Ana
authors.initials: A
authors.lastname: Stanciu
authors.forename: Adrian
authors.initials: A
authors.lastname: Zugravu
authors.forename: Liliana
authors.initials: L
authors.lastname: Bârsan
authors.forename: Daniela
authors.initials: D
authors.lastname: Dumitru
authors.forename: Mariana
authors.initials: M
authors.lastname: Lipan
authors.forename: Gabriel
authors.initials: G
authors.lastname: Mircescu
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000740:Anemia / Q000097:blood / Q000175:diagnosis* / Q000188:drug therapy* / Q000209:etiology / Q000378:metabolism; D001853:Bone Marrow / Q000737:chemistry / Q000378:metabolism*; D002908:Chronic Disease; D005260:Female; D006454:Hemoglobins / Q000032:analysis; D006801:Humans; D007262:Infusions, Intravenous; D007501:Iron / Q000008:administration & dosage* / Q000032:analysis / Q000378:metabolism*; D007674:Kidney Diseases / Q000097:blood / Q000150:complications / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D055815:Young Adult
chemical_list: D006454:Hemoglobins; D007501:Iron