Reticulocyte hemoglobin equivalent as a marker to assess iron deficiency: A large pediatric tertiary care hospital study

Introduction: Detection of iron deficiency (ID) remains challenging. We aimed to evaluate the performance of reticulocyte hemoglobin equivalent (Ret-He) as a potential diagnostic marker to assess ID and iron deficiency anemia (IDA) in a large pediatric cohort.Methods: A total of 3158 patients (aged 15 days to 19 years with a median age of 8.5 years; 60.2% female) were retrospectively studied. Statistical analysis was performed (a) to evaluate relationship of Ret-He with other relevant complete blood count and iron panel parameters; (b) to compare the levels of Ret-He in ID and IDA groups to a control group; and (c) to assess sensitivity and specificity of Ret-He in ID, IDA, and anemia without ID groups.Results: Ret-He values were significantly positively correlated to ferritin and transferrin saturation (TSAT). The median Ret-He was significantly lower in ID. A Ret-He cutoff of <= 30.0 pg distinguished cases of ID from the control group with a sensitivity of 90.2%, specificity of 59.5%, and area under curve (AUC) of 0.88. Ret-He showed better diagnostic performance in the IDA group and acceptable performance for ID without anemia. The sensitivity, specificity, and AUC were 90.1%, 80.9%, and 0.93 for IDA at cutoff value of <= 27.4 pg, and 80.8%, 51.1%, and 0.70 for ID without anemia at cutoff value of <= 30.8 pg, respectively.Conclusion: Our large pediatric tertiary care hospital study demonstrates that Ret-He is a reliable marker to help confirm IDA in pediatric population. However, further studies are needed for its use to capture the early stages of ID.