Discrimination of Iron Deficiency, Alpha and Beta Thalassemia on the Basis of Red Cell Distribution Width and Reticulocyte Indices.

Background The two major causes of microcytic anemia are iron deficiency and thalassemia. In clinical practice, in some cases, differentiation of microcytic and hypochromic anemia become difficult on the basis of traditional red cell parameters. This study primarily aimed to evaluate the usefulness of red cell distribution width (RDW), immature reticulocyte fraction (IRF), and reticulocyte hemoglobin equivalent (Ret-He) in the discrimination of alpha thalassemia, beta thalassemia, and latent iron deficiency. Methods In this retrospective study laboratory data including complete blood counts of females diagnosed with alpha thalassemia, beta thalassemia, and latent iron deficiency were retrospectively reviewed. Receiver operating characteristic (ROC) curve was constructed to evaluate the applicability and discriminatory efficiency of RDW, IRF, and Ret-He. Results Sensitivity and specificity of RDW-CV and RDW-SD was lower in the alpha thalassemia and beta thalassemia groups. Immature reticulocyte fraction (IRF) and reticulocyte hemoglobin equivalent (Ret-He) were significantly higher in the iron deficient group as compared to alpha and beta thalassemia. Conclusions In alpha and beta thalassemia, RDW-SD and RDW-CV were found to be poor discriminators. Sig-nificantly reduced levels of Ret-He were observed in alpha thalassemia and beta thalassemia in comparison to iron deficient group. While iron deficient group was characterized by increased values of RDW-SD, RDW-CV, IRF, and Ret-He.