The role of reticulocyte hemoglobin equivalent on the evaluation of iron deficiency and iron deficiency anemia in pediatric cyanotic heart disease: a diagnostic study in Indonesia

Background In light of prolonged hypoxia, children with cyanotic heart disase (CHD) are at a high risk of developing iron deficiency iron deficiency (ID) and iron deficiency anemia (IDA). Reticulocyte hemoglobin equivalent (Ret-He) is a novel and dependable indicator for assessing iron status. However, there has been no previous study regarding cut-off value in pediatric CHD group. The purpose of this study is to assess the role of Ret-He and to establish cut-off points in the diagnosis of iron deficiency and IDA in pediatric cyanotic heart disease. Method This study was conducted in two tertiary hospitals in Jakarta, Indonesia. 59 children with CHD, aged 3 months to 18 years, were enrolled consecutively. To determine iron status, hematological parameters (hemoglobin, hematocrit, mean corpuscular volume, mean corpuscular hemoglobin) and biochemical parameters for iron status (serum ferritin, transferrin saturation) were analysed and compared to Ret-He levels. The receiver operating characteristic (ROC) analysis was performed for the Ret-He cut-off points for ID and IDA. Sensitivity, specificity, positive and negative predictive value were calculated for each cut-off point. Result Normal iron status was identified in 27 (45.8%) subjects, ID in 8 (13.5%) subjects, and IDA 24 (40.7%) subjects. The ID cut-off value for Ret-He is 28.8 pg (sensitivity 75%, specificity 85.2%, PPV 60%, NPV 92%, and AUC 0.828) and the Ret-He cut-off point for IDA is 28.15 pg (sensitivity 75%, specificity 88.9%, PPV 85.7%, NPV 80%, and AUC 0.824). Hemoglobin should be used in conjunction with Ret-He. ID might be detected in this cohort with Ret-He 28.8 pg and hemoglobin > 16,5 g/dL. While Ret-He 28.15 pg or Ret-He 28.15-28.8 pg with hemoglobin 16.5 g/dL could be used to diagnose IDA. Conclusion The reticulocyte hemolgobin equivalent could be utilised as an iron status parameter in pediatric CHD, with a cut-off value of 28.8 pg for ID and 28.15 pg for IDA.