DIALYSIS – TRANSPLANTATION
Kidney International (1999) 56, 1113–1119; doi:10.1046/j.1523-1755.1999.00627.x
Factors determining the percentage of hypochromic red blood cells in hemodialysis patients
Christophe Bovy, Chantal Tsobo, Linda Crapanzano, Georges Rorive, Yves Beguin, Adelin Albert and Jean-Michel Paulus
Services of Nephrology, Hematology and Medical Statistics, University Hospital, Sart Tilman, Liège, Belgium
Correspondence: Christophe Bovy, M.D., Service of Nephrology, C.H.U.-Sart Tilman, B35-4000 Liege, Belgium. E-mail: cbovy@student.ulg.ac.be
Received 13 July 1998; Revised 12 February 1999; Accepted 3 April 1999.
Abstract
Factors determining the percentage of hypochromic red blood cells determines iron status in hemodialysis patients.
Background
Determination of the percentage of hypochromic red blood cells (RBC; %HYPO) has been advocated as a sensitive index of functional iron deficiency during erythropoietin (EPO) therapy in hemodialyzed patients.
Methods
The significance of %HYPO in chronic renal failure was evaluated in 64 chronically hemodialyzed patients. The linear correlation was determined between %HYPO and 13 variables, including age, sex, weight, C-reactive protein (CRP), ferritin, transferrin (Tf), Tf saturation, soluble Tf receptor (sTfR), serum iron (SI), urea, parathormone, dialysis dose (Kt/V), dose of EPO administered (EPO), and absolute reticulocyte count. Multiple regression analyses were then performed to select the parameters that jointly provide the best prediction of %HYPO.
Results
Univariate analysis showed significant correlations between %HYPO and iron parameters (sTfR, Tf saturation, SI, and ferritin, in decreasing order), EPO, reticulocyte count, and CRP. Multivariate analysis yielded an equation showing that the variation of %HYPO is essentially associated with the combined changes in sTfR, CRP, and EPO dosage.
Conclusions
%HYPO is a meaningful and inexpensive parameter that reflects the integrated effects of iron stores, inflammation, and erythropoietic stimulation on iron availability in hemodialyzed patients. Among iron exchange parameters, sTfR is the best predictor of %HYPO, followed by Tf saturation, SI, and ferritin.
Keywords:
erythropoietin, dialysis, iron deficiency, chronic renal failure, soluble transferrin receptor, red blood cells, anemia
Abbreviations:
CHr, reticulocyte hemoglobin content; CRP, C-reactive protein; EPO, erythropoietin; Hb, hemoglobin; %HYPO, percentage of hypochromic red blood cells; IL-1, interleukin-1; Kt/V, dialysis dose; MCV, mean corpuscular volume; RBC, red blood cells; SI, serum iron; sTf, soluble transferrin; sTfR, soluble transferrin receptor; Tf, transferrin; TNF-
, tumor necrosis factor-
