Diagnostic utility of microcytic and macrocytic parameters in anemia: A novel study from North India using hematology analyzer HORIBA Yumizen 1500

Background: Microcytic% (MIC%) and Macrocytic% (MAC%) are novel red blood cell parameters generated by the HORIBA Yumizen 1500 hematology analyzer. This study aims to establish normal reference ranges for MIC and MAC and evaluate their diagnostic significance across different morphological types of anemia. Aims and Objectives: This study aims: (1) To establish the normal reference ranges for MIC and MAC in healthy individuals in north Indian population. (2) To analyze MIC and MAC variations across different morphological types of anemia. Materials and Methods: This cross-sectional observational study is conducted in two phases. First, normal reference ranges for MIC and MAC were established using data from 282 healthy individuals. Further, 500 anemia cases was analyzed to evaluate MIC and MAC reference ranges. The anemia cases were classified morphologically into Microcytic hypochromic, Macrocytic, normocytic normochromic, and dimorphic anemia. Results: The reference ranges determined from the healthy population for male was MIC 0.14–4.36 and MAC 1.89–4.81 and female MIC 0.55–3.63 and MAC 1.8–3.65. Conclusion: MIC and MAC provide rapid, automated, and cost effective morphological insights into anemia subtypes. Elevated MIC correlates strongly with microcytosis, whereas increased MAC indicates macrocytosis. These parameters serve as valuable adjuncts to conventional hematological indices for anemia classification.