Abstract:Objective Although many studies have shown the significance of hematologic parameters in the diagnosis of thalassemia in adults, no related reports were found in neonates. This study aimed to evaluate the value of mean corpuscular volume (MCV), red cell distribution width (RDW) and erythrocyte fragility in the diagnosis of neonatal thalassemia.Methods A total of 386 hospitalized newborns with hyperbilirubinemia were enrolled in this study. They were divided into two groups: Thalassemia group (n= 35)and Non-thalassemia group(n=351) according to the results of thalassemia gene diagnosis. MCV, erythrocyte fragility and RDV were detected. Their ROC curves were made to calculate the areas under ROC (AUC ROC), the cut-offs,sensitivity and specificity of each marker in the diagnosis of thalassemia.Results Both MCV and erythrocyte fragility were significantly lower in the Thalassemia group than in the Non-thalassemia group (80±8 fL vs 94±9 fL, 31%±13% vs 46%±14%,P< 0.01). No differences were observed between the two groups for RDW. AUC ROCs of MCV, RDW and erythrocyte fragility in the diagnosis of thalassemia were 0.877, 0.630 and 0.796, respectively. The cut-offs of MCV, RDW and erythrocyte fragility was 88 fL, 15.9%, and 37.5%, respectively. The sensitivity and specificity of MCV were 92% and 73.5%, respectively, 73% and 58% for RDW and 85% and 75% for erythrocyte fragility. Conclusions Both MCV and erythrocyte fragility can serve as markers for the diagnosis of neonatal thalassemia, and MCV appears to be a better one.