TFRC and Schnyder corneal dystrophy: By contrast, in children with SCD, ferritin and sTfR levels were almost twofold above the upper limit of normal ferritin and sTfR (558.9 ng/L for ferritin and 5.9 μg/mL for sTfR), while in the control group both concentrations were within the normal ranges (59.0 ng/L for ferritin and 2 μg/mL for sTfR).