Utilization of Discriminant Formulas in the Differentiation of Alpha Thalassemia, Beta Thalassemia, and Iron Deficiency in Premarital Setting.

BACKGROUND

Iron deficiency and thalassemia are two commonly encountered microcytic and hypochromic anemias. The primary objective was to find the best discriminant formula between alpha thalassemia and iron deficiency to be used in premarital screening centers. The secondary objective, was to find cutoff values that might differentiate alpha thalassemia, beta thalassemia, and iron deficiency collectively.

METHODS

A total of 224 females divided into four groups (normal, alpha thalassemia, beta thalassemia, and iron deficiency) were recruited in this study after carrying out complete blood count, hemoglobin electrophoresis, serum ferritin, and molecular analysis. Based upon the laboratory data, 26 discriminant formulas (DF) were applied to differentiate alpha thalassemia, beta thalassemia, and iron deficiency anemia. Receiver Operating Characteristic (ROC) curve was constructed and sensitivity, specificity, and Youden's index were determined.

RESULTS

In this study, Shine and Lal, Ehsani, Telissani, Sirachainan, Hisham, Kandhro 2, and Mantos indexes showed 100% sensitivity, specificity, Youden's index, and 1.00 AUC for differentiating alpha thalassemia from iron deficient group. Formulas that showed best sensitivity and specificity (100%) in the discrimination of beta thalassemia and iron deficiency were Mentzer, Shine & Lal, Sarivastava & Bevington, and Sirachainan index (AUC 1.00). AUC of Mentzer index was lower (0.988 vs. 1.00) in differentiating alpha thalassemia and iron deficiency than beta thalassemia and iron deficiency.

CONCLUSIONS

Almost all discriminant formulas can be utilized for the prediction of microcytic anemia in a premarital setup after excluding beta thalassemia; however, further confirmation is mandatory for genetic counselling and iron supplementation. Furthermore, Bordbar, Kerman index I, and Huber-Herklotz index showed the lowest performance in the discrimination of alpha thalassemia and iron deficiency.