Diagnostic Utility of Reticulocyte Hemoglobin Equivalent Parameter in the Evaluation of Microcytic Hypochromic Anemia – Our Experience from Northeast India

Abstract

Background: Reticulocytes are red blood cell precursors with an average lifespan of 1–2 days. Reticulocyte hemoglobin equivalent (Ret-He) is an early marker of iron deficiency (ID) erythropoiesis and reflects real-time information regarding the synthesis of young erythrocytes in the bone marrow. The objective of this study is to determine the diagnostic utility of Ret-He in patients having microcytic hypochromic anemia in comparison with serum ferritin and iron studies. Objectives: The objective of this study is to determine the diagnostic utility of the Ret-He parameter in patients having microcytic hypochromic anemia in comparison with the serum ferritin, iron studies and its role in routine hematological screening for nutritional deficiency anemia like ID. Design and Settings: The design involves observational study. Materials and Methods: A hospital-based observational study was carried out in a referral hospital. Hematological parameters were processed using Sysmex XN1000 (Sysmex Corporation, Kobe, Japan) analyzer and were compared with Serum iron studies using biochemistry analyzer (VITROS® 250 Chemistry System) from 201 participants who presented with microcytic hypochromic anemia. Main Outcome and Measures: Relationship of Ret-He parameter and its diagnostic utility for screening of iron-deficient states. Sample Size: The sample size was 201. Results: When serum ferritin is taken as “the gold standard” to detect ID, with Ret-He cutoff of 27.15 pg/cell, we found a statistically significant positive correlation between Ret-He and serum ferritin (P < 0.001). We found a sensitivity of 57.37% and specificity of 75.95% with area under the curve of 0.681, positive predictive value of 100%, negative predictive value of 3.8%, and accuracy of 62.19% for Ret-He in detecting ID anemia (IDA). Also found a statistically significant negative correlation between Ret-He and total iron binding capacity (P < 0.001). There was no statistical correlation between Ret-He and serum iron levels in our study. Conclusions: The present study suggests Ret-He is one of the better and more reliable hematological parameters indicating ID and, when used along with biochemical parameters like serum ferritin, can give valuable inputs in a better screening and diagnosis of IDA; hence proper treatment is possible. Limitations: The multicentric study is required to standardize Ret-He reference values, and follow-up to therapy of the subjects was not done. Additional hemoglobin variant analysis data would have been favorable to the study.