Hepcidin on 24-hour urine collection: preanalytical aspects and correlation with ferritin levels.
BACKGROUND
Urine hepcidin measurement is a potential non-invasive tool for assessing iron stores. However, hepcidin, due to its amphipathic structure, tends to aggregate and to adhere to surfaces in a protein-poor environment. In this study, we assessed the effect of solid bovine serum albumin (BSA) at different final concentrations (0, 2.5 or 5 g/L) in limiting the loss of hepcidin in spot urine samples. We also explored how hepcidin measured on plasma, spot or 24-hour urine collections can identify iron deficiency.


METHODS
Hepcidin levels were quantified on plasma, spot (with or without BSA) or 24-h urine collections for 33 volunteers. Hematological and iron status parameters were measured for each individual. The ability to detect iron deficiency (defined as a ferritin level <30 μg/L) based on plasma, spot or 24-h urine collections hepcidin levels was assessed by the means of receiver operator curves analysis.


RESULTS
The addition of BSA into urine prior to sample collection prevented hepcidin loss by 13.3% (mean) in spot urine samples whatever the amount. The areas under the receiver operator curves obtained for detecting iron deficiency were respectively 0.94 and 0.93 for hepcidin levels obtained on plasma and 24-h urine collections.


CONCLUSIONS
In this study, we showed that the addition of solid BSA into urine sample collection containers could prevent aggregation of hepcidin and that 24-h urine hepcidin levels could be as efficient as plasma concentrations for identifying iron deficiency.
a Department of Clinical Chemistry , Hôpital Erasme, Université Libre De Bruxelles , Brussels , Belgium.
Fleur
F
Wolff
a Department of Clinical Chemistry , Hôpital Erasme, Université Libre De Bruxelles , Brussels , Belgium.
Marie
M
Gentelet
a Department of Clinical Chemistry , Hôpital Erasme, Université Libre De Bruxelles , Brussels , Belgium.
Béatrice
B
Gulbis
a Department of Clinical Chemistry , Hôpital Erasme, Université Libre De Bruxelles , Brussels , Belgium.
Frédéric
F
Cotton
D000328:Adult; D018798:Anemia, Iron-Deficiency / Q000097:blood / Q000175:diagnosis* / Q000652:urine; D015415:Biomarkers / Q000097:blood / Q000652:urine; D005260:Female; D005293:Ferritins / Q000097:blood / Q000652:urine*; D064451:Hepcidins / Q000097:blood / Q000652:urine*; D006801:Humans; D008297:Male; D008875:Middle Aged; D012372:ROC Curve; D059349:Urine Specimen Collection; D055815:Young Adult
D015415:Biomarkers; D064451:Hepcidins; D005293:Ferritins
Anemia; ferritin; hepcidin; iron; urine collection