Gestational Age-Specific Reference Ranges of Hepcidin in Cord Blood

Abstract

Background: Iron deficiency (ID) contributes to anaemia of prematurity, and hence the reliable assessment of iron nutrition status appears to be mandatory. Objective: To establish gestational age (GA)-specific reference ranges for hepcidin concentrations in cord blood [Hep_(CB)] of preterm and term infants and to identify pre- and perinatal confounding factors. Methods: This is a prospective observational study including 221 infants (GA at birth: 24-42 weeks). Hep_(CB) along with complete blood counts, ferritin and parameters of inflammation and clinical data were recorded. Data are presented as medians (IQR). Results: The Hep_(CB) of very preterm infants (GA <30 weeks, n = 40) was 26.9 ng/ml (13.5-63.1), for moderately preterm infants (GA 30-36 weeks, n = 81) it was 45.9 ng/ml (24.7-74.5) and for term infants (GA ≥37 weeks, n = 100) it was 103.9 ng/ml (61.4-149.2). The Hep_(CB) of infants with ID was lower [36.9 ng/ml (18.0-58.3)] than that of iron-replete infants [86.6 ng/ml (51.9-143.8)]. The Hep_(CB) of infants delivered by elective caesarean section was lower [38.3 ng/ml (15.5-73.7)] than that of infants after spontaneous vaginal delivery or secondary caesarean section [80.3 ng/ml (48.5-137.6)]. Infants with a standard deviation score for birth weight (SDS_BW) <-2 had a lower Hep_(CB) [23.1 ng/ml (11.7-61.5)] compared to infants with SDS_BW ≥-2 [71.1 ng/ml (34.0-121.7)]. The highest Hep_(CB) (437.6 ng/ml) was recorded in an infant with Enterococcus faecalis sepsis. Multiple logistic regression analysis confirmed ferritin, GA and mode of delivery as important factors associated with Hep_(CB). Conclusion: This is the first report on GA-specific reference ranges for Hep_(CB) in preterm infants. Whereas iron stores, GA and mode of delivery were associated with Hep_(CB), the association with inflammation and intra-uterine growth retardation was less clear.