Reticulocyte hemoglobin content as a marker of iron status in patients receiving maintenance hemodialysis

Background. Patients with renal anemia who show a poor response to erythropoietin might have iron insufficiency. Reticulocyte hemoglobin content (CHr) was measured in hemodialysis patients, and its potential as a marker for iron status was assessed by comparing CHr with ordinary markers. Methods. Ninety-one patients receiving maintenance hemodialysis were enrolled. Venous sampling was performed twice, at a 3-month interval. During the interval, none of the patients received any iron agent and there was no alteration in their erythropoietin doses. CHr was measured with an automated blood cell counter. Simultaneously, ordinary markers for iron status, such as hematocrit (Ht), mean hemoglobin content (CH), serum iron (Fe), ferritin (Fr), and transferrin saturation (TSAT), were measured. CHr was compared with these markers. Results. CHr randed from 24.1 to 34.7 pg, with a mean of 31.0 pg. CHr correlated with CH (P < 0.001), Fr (P < 0.01), Fe (P < 0.001), and TSAT (P < 0.001), but not with Ht. When patients were divided into two groups according to the CHr : CH ratio (CHr : CH ≧ 1 and CHr : CH < 1), there was no difference in any parameter between the two groups in the first measurement. In the second measurement, done after a 3-month interval, patients with CHr : CH ≧ 1 showed significantly higher values for CHr (P < 0.001), CH (P < 0.01), Fe (P < 0.05), and TSAT (P < 0.05) than patients with CHr : CH < 1. Conclusions. It was suggested that the CHr : CH ratio would predict changes in the state of iron supply. CHr might be a potential marker for monitoring renal anemia.