Utility of reticulocyte haemoglobin content and immature reticulocyte fraction in early diagnosis of latent iron deficiency in whole blood donors

The present study was planned to assess the clinical utility of reticulocyte haemoglobin content (CHr) and immature reticulocyte fraction (IRF) in the early detection of latent iron deficiency in blood donors.The prospective longitudinal observational study was conducted using the purposive sampling method. Written informed consent was obtained and donors were allocated into the first-time (FTD) and regular donor (RD) group. The enrolled blood donors (n = 205 in each group) were followed up for two subsequent whole blood donations. Haemoglobin (Hb), CHr, IRF and serum ferritin values were recorded at enrolment and two follow-ups.The sensitivity of CHr in detecting iron-deficient erythropoiesis (serum ferritin values ≤ 26 μg/dl) was 45% and 56.7%, specificity 96.7%, positive predictive value (PPV) 85.6% and 90.8% and negative predictive value (NPV) 80.1% and 78.7%, respectively in FTD and RD cohorts. The sensitivity of IRF was 45.1% and 44.8%, specificity 93.4% and 97.1%, PPV 74.8% and 90.4% and NPV 79.6% and 74.5%, respectively in both the cohorts. The sensitivity of CHr in detecting absent iron stores (serum ferritin values ≤ 15 μg/dl) was 66.2% and 74.4%, specificity 92% and 90.6%, PPV 56.7% and 68.7% and NPV 94.5% and 92.8% among FTD and RD cohort, respectively. The sensitivity of IRF was 72.7% and 65.3%, specificity 90.3% and 94.3%, PPV 54.4% and 76% and NPV 95.4% and 90.8%, respectively in both the cohorts.Reticulocyte hemoglobin content and IRF can be used along with complete blood count for early detection of iron deficiency in blood donors using the same blood sample at no extra cost.