title: Role of C-reactive protein, reticulocyte haemoglobin content and inflammatory markers in iron and erythropoietin administration in dialysis patients.
abstract: OBJECTIVE
  C-reactive protein (CRP) is an acute phase reactant protein, which becomes elevated in response to inflammation, infections or malignancies. These conditions are well known causes of bone marrow hyporesponsiveness and erythropoietin resistance in dialysis patients. The role of iron-deficiency as a cause of hyporesponsiveness under these conditions is not clear. Reticulocyte haemoglobin content (CHr) is one of several iron indices used to determine iron deficiency in dialysis patients. The aim of this study is to evaluate the role of CRP and CHr in iron administration and anaemia management in dialysis patients.
  
  
  METHODS
  In 47 haemodialysis patients with ferritin levels of >500 ng/mL, CRP, CHr, transferrin saturation (TSAT), other markers and erythropoietin dose were evaluated. Patients with CRP < 5 mg/L (Group A) were compared to patients with CRP > 5 mg/L (Group B).
  
  
  RESULTS
  Ferritin levels in the two groups were not different. Weekly erythropoietin was significantly different between the two groups. Group B required an average of 121% more erythropoietin than Group A to maintain similar haemoglobin levels of 11-12 g/dL 36% of Group B had CHr < 29 pg versus 7% of patients in Group A. 39% of patients in Group B also had TSAT < 20% versus 0% in Group A. Group A also had more arteriovenous (AV) fistulae as dialysis access than group B.
  
  
  CONCLUSIONS
  Data indicate that low CHr, similar to low TSAT, could be associated with inflammatory process and erythropoietin resistance, but not necessarily with iron-deficiency. High CRP association with low CHr and low TSAT levels can explain the lack of response to further IV iron therapy. AV grafts, contrary to AV fistulae, are associated with high inflammatory markers and also with a higher erythropoietin requirement.
authors.affiliation: University of Cincinnati College of Medicine, Division Of Nephrology and Hypertension, Department of Internal Medicine, Cincinnati, Ohio 45267-0585, USA. mahmoud.elkhatib@uc.edu
authors.forename: Mahmoud
authors.initials: M
authors.lastname: El-Khatib
authors.forename: Heather J
authors.initials: HJ
authors.lastname: Duncan
authors.forename: K Shashi
authors.initials: KS
authors.lastname: Kant
mesh_terms: D000210:Acute-Phase Reaction / Q000097:blood / Q000276:immunology; D000368:Aged; D000740:Anemia / Q000188:drug therapy* / Q000209:etiology / Q000276:immunology; D015415:Biomarkers / Q000097:blood; D002097:C-Reactive Protein / Q000276:immunology / Q000378:metabolism*; D004351:Drug Resistance / Q000502:physiology; D004921:Erythropoietin / Q000008:administration & dosage*; D005260:Female; D005293:Ferritins / Q000097:blood; D006454:Hemoglobins / Q000378:metabolism*; D006801:Humans; D007501:Iron / Q000008:administration & dosage*; D007676:Kidney Failure, Chronic / Q000150:complications* / Q000276:immunology / Q000628:therapy; D008297:Male; D008875:Middle Aged; D006435:Renal Dialysis; D012156:Reticulocytes / Q000378:metabolism; D014168:Transferrin / Q000378:metabolism
chemical_list: D015415:Biomarkers; D006454:Hemoglobins; D014168:Transferrin; D004921:Erythropoietin; D002097:C-Reactive Protein; D005293:Ferritins; D007501:Iron