Diagnostic reliability check of red cell indices in differentiating Iron Deficiency Anemia (IDA) from Beta Thalassemia Minor (BTT)

Introduction: Iron deficiency anemia and beta-thalassemia trait are the two most common causes of hypochromic microcytic anemia. There are some discriminating functions (DFs) formula to differentiate these two conditions based on RBC s indices which would be compared the validity of the 14 various indices in this study. Methods: A total of 227 patients from 21st March to 21st June 2014 were studied by calculating DFs i.e. Keikhaei (KI), RDWI, Green King (G KI), England Fraser (E FI), Mentzer (MI), Shine Lal (S LI), Telmissani (TI), Ricerca (RI), Ehsani (EI), Keli (RBC) and 4 new indices (F1, F2, F3 F4). The study included 105 iron deficient patient and 122 beta-thalassemia trait cases (HbA2 3.5 HbA2 8%). The number of correctly diagnosed cases were determined and sensitivity, specificity, positive and negative predictive value and Youden index of each discrimination index were calculated. Results: None of the indices showed 100% sensitivity and specificity. C KI, KI, RDWI, E FI, F3, EI and MI showed the highest value in differentiating IDA from BTT. The lowest value was belong to S LI, F4 and F2 indices. Conclusion: Based on Youden index (YI), the value of discrimination function indices from highest to lowest was as follow: G KI KI RDWI E FI F3 Ei MI RBC F1 RI F2 F4 S LI.