Usefulness of measuring reticulocyte hemoglobin equivalent in the management of haemodialysis patients with iron deficiency

Abstract

The evaluation of iron status in dialysis patients provides information essential to the planning of adequate recombinant human erythropoietin treatment. The cellular iron status of the patients can be determined from the recently available measurement of reticulocyte hemoglobin equivalent (RET-He). RET-He is measured on the basis of automated fluorescent flow cytometry which in the reticulocyte channel, using a polymethine dye, also measures the mean value of the forward light scatter intensity of mature red blood cells and reticulocytes. These values equate with reticulocyte hemoglobin content. In this study, to clarify the accuracy of RET-He in diagnosing iron deficiency in dialysis patients, we initially compared RET-He with such iron parameters as serum ferritin levels, transferrin saturation and content of reticulocyte hemoglobin (CHr) which has been established as indicators of functional iron deficiency. Secondly, we investigated the changes in RET-He during iron supplementation for iron-deficient patients to determine whether this marker is a prospective and reliable indicator of iron sufficiency. The participants in this study were 217 haemodialysis patients. Iron deficiency was defined as havsing a transferrin saturation (TSAT) < 20% or serum ferritin < 100 ng/ml. Conventional parameters of red blood cells and RET-He were measured by on a XE-2100 automated blood cell counter (Sysmex). CHr was measured on an ADVIA120 autoanalyser (Siemens). RET-He mean value was 32.4 pg and good correlation (r = 0.858) between RET-He and CHr is obtained in dialysis patients. Receiver operating characteristic curve analysis revealed, values of the area was 0.776 and at a cutoff value of 33.0 pg, a sensitivity of 74.3% and a specificity of 64.9%, were achieved. Iron supplements given to the patients with low TSAT or ferritin, RET-He responded within 2 weeks, and this seemed to be a potential advantage of using RET-He in the estimation of iron status. RET-He is a new parameter, equivalent value to CHr, and is easily measurable on the widely spread and popular blood cell counter and is a sensitive and specific marker of iron status in dialysis patients.

Usefulness of Reticulocyte Hemoglobin Equivalent in Management of Regular Hemodialysis Patients with Iron Deficiency Anemia

“…Similar result was found in the study of Chuang et al (2003) and Miwa et al (2010) where a significant improvement in hemoglobin was found after 4 weeks of iron supplementation [3,8]. The increase in hemoglobin is not only due to improvement of iron status but also it may reflect resolution of an inflammatory state [12].…”

“…Previous study by Canals et al ) showed there was a good correlation between RET-He and TSAT (r = 0.543, p < 0.01) but a weak correlation between RET-He and serum ferritin (r = 0.279, p < 0.01) [8]. This study also showed there were lower correlations between RET-He and serum ferritin (r = 0.499, p < 0.0001) compared to RET-He and TSAT (r = 0.592, p < 0.0001).…”

“…RET-He is advantageous in that it has no interference with inflammatory conditions, has early response to iron therapy and lower cost compared to conventional parameters. Previous study from Brugnara et al (2006), Miwa et al (2010) and Buttarello et al (2010) showed that RET-He can be used as alternative parameters for iron deficiency anemia in regular hemodialysis patients [2,6,8]. Therefore, this study aims to assess diagnostic value of RET-He in identification of iron deficiency in regular hemodialysis patients and to investigate RET-He as early predictor of response to intravenous iron supplementation.…”

“…Since reticulocyte has a more rapid turnover in circulation than mature erythrocyte, it is hypothesized that reticulocyte may be more sensitive in detecting erythropoietic activity. RET-He can be measured with an existing common blood analyzer installed with upgraded software [8]. RET-He is advantageous in that it has no interference with inflammatory conditions, has early response to iron therapy and lower cost compared to conventional parameters.…”

Assessing Iron Status in CKD Patients: New Laboratory Parameters

“…Twenty nine pg is the cut off value that defines deficient erythropoiesis Several studies have demonstrated that Ret He and CHr have the same clinical meaning (Mast et al, 2008;Maconi et al, 2009;Miwa et al, 2010). The new Symex XE 5000 analyzer reports the percentages of hypochromic red cells; the reference range and the values in different types of anemia have been published (Urrechaga et al, 2009).…”