Gestational age-specific reference ranges of hepcidin in cord blood.

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 (SDSBW) <-2 had a lower Hep(CB) [23.1 ng/ml (11.7-61.5)] compared to infants with SDSBW ≥-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.