IL6 and Sepsis: Spearman correlation analysis showed that hemoglobin had a positive correlation with plasma EPO and sTfR/log ferritin (both P < 0.05, Additional file 1: Table S6), a negative correlation with plasma IL-6, hepcidin, ferritin and the RDW (all P < 0.05), but no correlation with plasma sTfR (P = 0.367) in patients with sepsis.