title: Percentage of hypochromic erythrocytes and reticulocyte hemoglobin equivalent predictors of response to intravenous iron in hemodialysis patients.
abstract: BACKGROUND
  Reticulocyte hemoglobin content and percentage of hypochromic red cells are incorporated into the European best practice guidelines on anemia management in chronic kidney disease. Sysmex XN analyzer (Sysmex Corporation, Kobe, Japan) reports reticulocyte hemoglobin equivalent (Ret-He) and the hypochromic fraction of erythrocytes (%Hypo-He). Our aim was to assess the value of these parameters, in terms of the sensitivity and specificity for detecting functional iron deficiency, in hemodialysis (HD) patients.
  
  
  METHODS
  Forty HD patients in the maintenance phase of erythropoietin therapy were included. Intravenous iron supplementation was interrupted at least 3 weeks before recruitment. Two samples were analyzed for each patient: the baseline after the iron-free period and the second sample after 4 weeks of IV iron administration. Hemogram and biochemical parameters of the iron status were measured. Patients were classified as responders or nonresponders to an iron load; responders had an increase in Hb of at least 10 g/L after iron administration, compared to the baseline. To identify the efficiency of the test for predicting the response to iron administration, receiver operating characteristic analysis (ROC) was performed.
  
  
  RESULTS
  According to the established criteria, 21 patients were responders and 19 nonresponders. ROC analysis results: Ret-He area under curve (AUC) was 0.84 (95% CI 0.64-0.93), at cutoff 30.8 pg, sensitivity 78.7%, and specificity 87.2%. % Hypo-He AUC was 0.78 (95% CI 0.64-0.91), at cutoff 2.4%, sensitivity 72.2%, and specificity 88.1%.
  
  
  CONCLUSIONS
  % Hypo-He and Ret-He are reliable parameters for the study of erythropoiesis status in HD patients.
authors.affiliation: Hematology Laboratory, Hospital Galdakao - Usansolo, Galdakao, Vizcaya, Spain.
authors.forename: E
authors.initials: E
authors.lastname: Urrechaga
authors.affiliation: Hematology Laboratory, Hospital Galdakao - Usansolo, Galdakao, Vizcaya, Spain.
authors.forename: O
authors.initials: O
authors.lastname: Boveda
authors.affiliation: Laboratory, Hospital Universitario Basurto, Bilbao, Vizcaya, Spain.
authors.forename: F J
authors.initials: FJ
authors.lastname: Aguayo
authors.affiliation: Laboratory, Hospital Universitario Basurto, Bilbao, Vizcaya, Spain.
authors.forename: P
authors.initials: P
authors.lastname: de la Hera
authors.affiliation: Nephrology. HD Unit. Hospital Galdakao - Usansolo, Galdakao, Vizcaya, Spain.
authors.forename: R I
authors.initials: RI
authors.lastname: Muñoz
authors.affiliation: Nephrology. HD Unit. Hospital Galdakao - Usansolo, Galdakao, Vizcaya, Spain.
authors.forename: I
authors.initials: I
authors.lastname: Gallardo
authors.affiliation: Department of Pharmacology and Physiology, Faculty of Medicine, University of Zaragoza, Zaragoza, Spain.
authors.forename: J F
authors.initials: JF
authors.lastname: Escanero
mesh_terms: D061605:Administration, Intravenous; D004912:Erythrocytes / Q000737:chemistry*; D004920:Erythropoiesis / Q000187:drug effects; D004921:Erythropoietin / Q000494:pharmacology / Q000627:therapeutic use; D006454:Hemoglobins / Q000032:analysis* / Q000187:drug effects; D006801:Humans; D007501:Iron / Q000008:administration & dosage* / Q000494:pharmacology; D008875:Middle Aged; D011237:Predictive Value of Tests; D006435:Renal Dialysis / Q000009:adverse effects*; D051436:Renal Insufficiency, Chronic / Q000097:blood / Q000188:drug therapy; D012156:Reticulocytes / Q000737:chemistry*; D012680:Sensitivity and Specificity
chemical_list: D006454:Hemoglobins; D004921:Erythropoietin; D007501:Iron
keywords: Erythropoiesis; Iron availability; hemodialysis; hypochromic erythrocytes; reticulocyte hemoglobin content