Exploring Beta-thalassemia and Iron-deficiency Anemia by Red Cell Indices and Formula: A Study among the Tribes Residing in Selected Districts of Tamil Nadu

Background: India is home to 1–1.5 lakh children with thalassemia, with Tamil Nadu having a notable prevalence of this condition, ranging from 1% to 3%. Based on the National Family Health Survey round 5 (NFHS-5) reports, it was found that the percentage of children aged 6–59 months with anemia was 67.1%. Interestingly, in Tamil Nadu, the prevalence of anemia in the same age group was substantially higher at 57.4%. Beta-thalassemia trait (BTT) and iron-deficiency anemia (IDA) are common blood disorders that are difficult to distinguish from each other because they share similar symptoms. Hence, this study aims to investigate the utility of red blood cell (RBC) indices and the established formula for differentiating BTT from IDA among the tribes residing in selected districts of Tamil Nadu. Methods: This cross-sectional study includes the data related to RBC parameters from 400 study participants belonging to the tribes residing in Dharmapuri, Kancheepuram, Salem, and Nilgiris. Descriptive statistics, the indices, sensitivity, and specificity were computed. The Chi-square test was performed at 5% level of significance. Results: The mean and standard deviation of Mentzer’s index (MI), red cell distribution width index (RDWI), and the formula red cell distribution width (RDW)/RBC were 16.80 ± 4.54, 271.06 ± 86.14, and 3.53 ± 1.04, respectively. The sensitivity and specificity of MI were 0.539 and 0.698, RDWI were 0.742 and 0.357, and the formula RDW/RBC were 0.787 and 0.331, respectively. The area under the curve was found to be higher for MI (0.6354) when compared to the other two indices. Conclusion: To confirm the diagnosis of hemoglobinopathies, additional tests such as peripheral smear, iron studies, and hemoglobin electrophoresis/high-performance liquid chromatography (HPLC) are needed. Molecular studies might be performed to confirm the presence of mutations.