Assessment of serum bioactive hepcidin-25, soluble transferrin receptor and their ratio in predialysis patients: Correlation with the response to intravenous ferric carboxymaltose

Background: No reliable biomarker exists to predict responsiveness to intravenous (IV) iron (Fe) in iron deficient patients with CKD. We aimed to investigate the clinical value of bioactive Hepcidin-25 and soluble Transferrin Receptor (sTfR) levels in predialysis patients. Patients and methods: In this prospective study 78 stable stage III-IV CKD predialysis patients with (responders) (40 patients) andwithout (non-responders) (38 patients) adequate erythropoiesis after IV administration of ferric-carboxymaltose (FCM). Patients were divided in two groups according to their response to IV administration of ferric-carboxymaltose (FCM). Along with measurements of common hematologic and blood chemistry parameters, determinations of sTfR and bioactive Hepcidin-25 were performed. Results: Hepcidin-25 levels were lower in the responders (p = 0.025), while sTfR and sTfR/Hepcidin-25 ratio were higher (p < 0.01 and p = 0.002 respectively). Diagnostic efficacy indicated cut off point of 1.49 for Hepcidin-25 had sensitivity 84% and specificity 48%, while cut off point of 11.21 for sTfR/Hepcidin-25 ratio had sensitivity 82% and specificity 52% to predict correctly response to iron supplementation therapy. Furthermore, log sTfR/Hepcidin-25 correlated negatively with hs-CRP (p = 0.005) and IL-6 (p < 0.04) in non-responders, while such correlations were not found in responders (p > 0.05). Conclusions: These results suggest that lower Hepcidin-25, aswell as higher sTfR and sTfR/Hepcidin-25 ratio were significant predictors of favorable hemoglobin response within a month after IV administration of FCM in patients with CKD. Further experiments and clinical studies in other groups of patients are needed to better elucidate the role of Hepcidin-25 and sTfR/Hepcidin-25 ratio as predictors of response to intravenous iron administration. (C) 2016 Elsevier Inc. All rights reserved.