Evaluation of the hypochromic erythrocyte and reticulocyte hemoglobin content provided by the Sysmex XE-5000 analyzer in diagnosis of iron deficiency erythropoiesis

Background: Iron deficiency represents the most frequent cause of anemia. To diagnose iron deficiency some biochemical tests such as serum ferritin and the transferring saturation percent (TSAT%) are usually used. Recently, some hematological parameters such as mean reticulocyte hemoglobin content (CHr or Ret-He) and percentage of hypochromic RBCs (Hypo% or % Hypo-He) were proposed as alternative to biochemical tests. In this study, the analytic performance and the diagnostic efficiency of these two parameters provided by Sysmex XE5000 analyzer on iron deficiency patients with or without anemia (IDA and ID, respectively) were evaluated. Methods: One hundred and sixty-four healthy adults, 58 with IDA, 21 with iron depleted stores (ID), 23 with beta-thalassemia trait, and 24 with non iron deficiency anemia were selected. The gold standard used to define iron deficiency was the coexistence of serum ferritin below 15 mu g/L (12 in women) and TSAT <16%. Results: For % Hypo-He, the best cut-off value for both IDA and ID is 0.9% while for Ret-He is 30.6 pg. For both parameters the performance was better to diagnose IDA (AUC, 0.96 and 0.98) than ID (AUC, 0.93 and 0.95). The Ret-He behavior was always slightly better than that of % Hypo-He. Conclusions: The use of these two parameters is useful to detect iron deficiency conditions if the hemoglobin synthesis has already been compromised.