Evaluation of Iron Status by Reticulocyte Haemoglobin Content (Chr) in Chronic Kidney Disease Patients on Haemodialysis and Erythropoietin

Diagnosing iron deficiency with currently available tests is difficult in patients with chronic kidney disease (CKD) due to the inflammatory state associated with uraemia. The aim of this study was to evaluate the importance of reticulocyte haemoglobin (CHr) as a diagnostic tool of iron deficiency and a predictor to intravenous iron therapy in a cohort of CKD patients on haemodialysis in Sri Lanka. This was a descriptive cross sectional study involving hundred (100) patients with CKD on regular haemodialysis and erythropoietin. Patients were categorised into groups depending on serum ferritin, transferrin saturation and reticulocyte haemoglobin (CHr). All patients with CHr < 29 pg were treated with a single dose of intravenous(IV) iron 500 mg. The CHr was measured 72 h after the IV iron treatment to assess the response. Within the population mean haemoglobin was 9.27 g/dL, mean serum ferritin was 243.5 ng/mL, mean transferrin saturation was 18.6% and mean CHr was 29.2 pg. Thirty three of the 100 patients (33%) were subjected to IV iron therapy and there was a significant increase of CHr 72 h after IV iron treatment (p < 0.001). As a diagnostic tool in iron deficiency in CKD patients on haemodialysis, CHr showed a sensitivity of 56%, specificity of 73% and positive predictive value of 84%. Reticulocyte haemoglobin (CHr) can be used as an early predictor of response to IV iron therapy. However, further evaluation is necessary to consider CHr as a diagnostic tool to detect iron deficiency in CKD patients on haemodialysis.