Study of serum ferritin in donors of two red blood cells units collected by apheresis

ObjectiveTo analyze the recovery of iron stores without supplementation, when keeping an interval of six months between donations.Material and methodsFrom April 2007 to May 2011, 308 regular and voluntary donors were selected. The apheresis collections were performed using ALYX® Component Collection System-Fenwal™. The hematological parameters were analyzed using the Cell DIN Sapphire – Abbot Diagnostics, and the serum ferritin by sandwich immunoassay method with fluorescence detection in final phase (ELFA) – Vidas® Ferritin–Biomérieux SA. A descriptive statistical analysis was performed for each hematological parameters and serum ferritin.ResultsThe median hemoglobin concentration was 15.6 g/dL (14, 18.4) in the first procedure and remains constant at subsequent donations. The ferritin median concentration was 64.6 μg/L (7.2, 886). A decrease of 15.6% was observed when compared the first to the second procedure with a median 54.6 μg/L (8.3, 213.7). Paradoxically, this decrease is not evident in the subsequent procedures, where an increase of 14.6% and 3.4% for the third and fourth procedure respectively was observed. Changes in ferritin values show statistically significant differences between the first and second collection, but this difference disappeared in subsequent donations. The analysis of MCH in each collection indicates that the significant difference between first and second donation (p1–2 < 0.05) and between first and third (p1–3 = 0.015), agree with the greatest decline of the ferritin found between procedures and the beginning of the stabilization of ferritin levels.CommentaryThe determination of ferritin appears not to be the most important parameter to consider at the time of donor selection and suggests that other factors unrelated to the donation may play a significant role. A decrease in serum ferritin was observed at the beginning, but it seems to attend a recovery and stabilization in the successive procedures.