Serum hepcidin and ferritin as markers of iron deficiency in premature infants born at less than 32 weeks of gestation: prospective observational study.

BACKGROUND: Preterm infants born at less than 32 weeks of gestation are at higher risk of low total iron stores (iron deficiency). Serum ferritin is used as a valid total iron stores and iron deficiency biomarker, usually as a combination of ferritin and red blood cell counts. METHODS: Serum hepcidin and ferritin values and red blood cell counts were obtained from 37 of 40 included premature infants born at less than 32 weeks of gestation at risk of iron deficiency. The first sample was obtained in the first week of life, and the second at transfer from the Neonatal intensive care unit to the maternity ward, when serum ferritin level below 25 µg/L has been defined as very low total iron stores (iron deficiency). RESULTS: Ferritin median levels decreased from a median value of 152 µg/L at the first measurement to 54 µg/L at the second measurement. Hepcidin median levels also decreased from 30.1 µg/L to 2.1 µg/L. We found a positive and statistically significant correlation between levels of ferritin and hepcidin at both measurements (r = 0.57; p < 0.001 and r = 0.72; p < 0.001, respectively). Compared to serum hepcidin, ferritin at the first measurement has not statistically significant higher power in predicting children with iron deficiency before discharge from the hospital. CONCLUSIONS: We found a correlation between ferritin and hepcidin levels. Nevertheless, hepcidin does not have a worse power in predicting children with iron deficiency compared to ferritin.