title: [Clinical usefulness of the reticulocyte hemoglobin equivalent in chronic hemodialysis patients].
abstract: BACKGROUND
  Iron deficiency is the main cause of failure to respond to erythropoietin (EPO) in haemodialysis patients. Several laboratory tests to detect the deficiency, ferritin and transferrin saturation (TSat) are the most commonly used but its limitations in this patient population are necessary to find other parameters to improve the identification of iron-deficient state.
  
  
  OBJECTIVE
  To evaluate the ability of Reticulocyte Hemoglobin Equivalent (RET-He) to predict iron deficiency, taking as a reference standard to the increase of hemoglobin in response to iron intake.
  
  
  METHODS
  44 patients on chronic hemodialysis and fixed-dose EPO received 400 mg of intravenous iron. Were measured Hb, Ret-He, IRF, and ferritin prior to iron administration. After 20 to 30 days of completion of loading the patients were classified as responders if hemoglobin increased by at least 0.8 g / L and non-responders if this increase did not occur.
  
  
  RESULTS
  25 patients were responders, the ROC curves analysis showed the Ret-He with the largest AUC of 0.862 similar to the AUC of 0.833 that showed the IST, but the first is more sensitive (72% CI 95%: 51-88% vs 52% 95% CI 31-72%) and similar specificity (94.7% CI 95%: 74-100% vs 100% 95% CI 82-100%). Ferritin AUC was 0.772 and finally the IRF AUC was 0.7. The Ret-He, to a cutoff of 29.5 pg was the best combination of sensitivity and specificity (72 and 94.7 respectively), and the sensitivity of the combination Ret-He/IST rose to 80% specificity 94.7%.
  
  
  CONCLUSIONS
  According to these results it could consider to Ret-He and the Ret-He/IST combination of clinical utility for the identification of the iron deficit in patients in chronic haemodialysis.
authors.affiliation: Laboratorio de Bioquímica Clínica del Hospital Privado de Córdoba, Córdoba, Argentina. andrea.eckhardt@hospitalprivadosa.com.ar
authors.forename: A
authors.initials: A
authors.lastname: Eckhardt
authors.forename: M A
authors.initials: MA
authors.lastname: Freiberg
authors.forename: J
authors.initials: J
authors.lastname: de la Fuente
authors.forename: W
authors.initials: W
authors.lastname: Douthat
authors.forename: R
authors.initials: R
authors.lastname: Capra
mesh_terms: D018798:Anemia, Iron-Deficiency / Q000175:diagnosis* / Q000209:etiology; D015415:Biomarkers / Q000097:blood; D015331:Cohort Studies; D004921:Erythropoietin / Q000627:therapeutic use; D005260:Female; D005293:Ferritins / Q000097:blood*; D006801:Humans; D007676:Kidney Failure, Chronic / Q000150:complications / Q000628:therapy*; D008297:Male; D008875:Middle Aged; D012372:ROC Curve; D006435:Renal Dialysis; D015203:Reproducibility of Results; D017701:Reticulocyte Count / Q000379:methods*; D012680:Sensitivity and Specificity
chemical_list: D015415:Biomarkers; D004921:Erythropoietin; D005293:Ferritins