Clinical Evaluation of Repeat Apheresis Donors in Japan

To ascertain the safety of repeat apheresis donation, hematological and biochemical tests were performed on 511 donors with a donation rate of over 6 times per year for a period of 12-19 months.Repeat donors who had apheresis more than 6 times in the previous year were chosen. Data for the repeat donors at the start of the experiments were compared with those at the end of the study. Blood samples were taken prior to donation. Serum protein, albumin, immunoglobulin G, A, and M, serum ferritin levels were determined by biochemical tests.When compared to prospective donors of 400 ml, WBC, lymphocytes, and serum ferritin levels were lower in a roughly frequency-dependent manner in female and male donor groups at the beginning of the study. All the data for the male group remained almost constant with increasing frequency of apheresis donation. However, in the female group, ferritin levels significantly decreased with over 21 donations.The present data showed that the serum ferritin level of the female donors decreased the most with increasing frequency of apheresis donation. The cumulative RBC left in the collecting chamber and for the laboratory test is discussed in relation to a possible cause of iron deficiency in frequent apheresis donors.