Albertine Donker

Chapter 7 230 Apart from diagnostic applications, multiple agents targeting the hepcidin/ferroportin axis are under development as novel therapeutics for iron disorders in adults. 19 In order to use hepcidin as a diagnostic tool and a therapeutic target, reference values of the healthy population are crucial. For adults, reference ranges of serum hepcidin (and its ratio to ferritin and TSAT) are available for our assay. 20,21 They have been constructed based on data from the general adult population (N~3,000), and have recently been converted to standardized reference ranges. 21,22 These data have revealed that in both men and women serum hepcidin concentrations are strongly associated with serum ferritin 20,23 and only marginally with circulating iron (TSAT). 20 Serum hepcidin concentrations in men are stable over age while in women concentrations are lower in premenopausal than in postmenopausal women. This is in agreement with the observation that serum ferritin concentrations tend to increase as women progress through menopause. 20 Implementation of serum hepcidin levels in clinical pediatrics is hampered by the lack of standardized reference values of healthy children from different age groups, relative to iron status. 24-26 Available studies concern either small series with limited age groups or series including children with (anemia of) inflammation. 16,27-31 As a first step to the implementation of serum hepcidin measurements in pediatric clinical practice, we established age- and sex-specific standardized serum hepcidin values relative to body iron indicators in healthy Dutch children aged 0.3-17 years. Our observations suggest a changing set point of serum hepcidin relative to body iron indicators during childhood.