Preanalysis in Serum Hepcidin Measurement.

Background: Hepcidin is a 25-amino peptide hormone that regulates iron homeostasis. Its serum quantification helps to provide the right therapeutic choice in iron-deficiency anemia and anemia in chronic diseases. Diurnal levels of serum iron might affect hepcidin secretion during the day. Blood collection time is an important part of the preanalytical phase of its quantification.

Methods: During the period 2013 - 2014, we collected blood samples for serum hepcidin quantification in 100 healthy controls. The samples were collected in vacuettes with serum separator gel at three different times during the day: 07:30 - 08:30, 12:00 - 13:00, and 16:00 - 17:00 hours. Hepcidin levels were measured with an ELISA method.

Results: We found a significant difference in serum hepcidin levels during the chosen three blood taking times. The normal range for Bulgarian population is 3.05 μg/L - 37.75 μg/L. The measured levels were: at 07:30 - 08:30 hours 12.2 μg/L (5.5 μg/L - 23.6 μg/L), 12:00 - 13:00 hours 14.1 μg/L (7.1 μg/L - 27.2 μg/L), and 16:00 - 17:00 hours 16.5 μtg/L (9.9 μg/L - 29.6 μpg/L) 10.7 < r < 1.0; p < 0.5 between 07:30 - 08:30 and 12:00 - 13:00 hours and p < 0.05 between 07:30 - 08:30 hours and 16:00 - 17:00 hours and 12:00 - 13:00 hours and 16:00 - 17:00 hours]. No significant differences were found for transferrin saturation between measured groups [0.1 < r < 0.3; p > 0.5].

Conclusions: In order to obtain the most correct results for serum hepcidin quantification (especially in border to referent range levels) in the preanalytical phase, it is important to consider the time of blood sampling.