Discriminant indexes to simplify the differential diagnosis between iron deficiency anemia and thalassemia minor in individuals with microcytic anemia

Abstract

SUMMARY INTRODUCTION: Microcytic anemias are very common in clinical practice, with iron deficiency anemia (IDA) and thalassemia minor (TT) being the most prevalent. Diagnostic confirmation of these clinical entities requires tests involving iron metabolism profile, hemoglobin electrophoresis, and molecular analysis. In this context, several discriminant indices have been proposed to simplify the differential diagnosis between IDA and TM. OBJECTIVE: The aim of this paper was to demonstrate the clinical relevance of the use of discriminant indices in individuals with microcytic anemia to simplify the differential diagnosis between iron deficiency anemia and minor thalassemia. METHODS: A bibliographic and cross-sectional search was performed in the PubMed, SciELO and LILACS databases, using the following descriptors: iron deficiency anemia, thalassemia minor, and differential diagnosis. RESULTS: More than 40 mathematical indices based on erythrocyte parameters have been proposed in the hematological literature in individuals with microcytosis. Green & King indexes (IGK), Ehsani index, and erythrocyte count (RBC) had excellent performances, especially when their efficacy was observed in adults and children. CONCLUSIONS: Confirmatory tests for differential diagnosis between IDA and TM require time-consuming and costly methods. Despite the excellent performances of IGK, Ehsani index, and RBC, none of them presented sufficient sensitivity and specificity to establish a diagnosis. However, they can provide a powerful additional tool for diagnostic simplification between IDA and TM.