Effect of serial plasma exchange sessions with albumin replacement on ABO antibody titers

Abstract

Background Donor shortage in kidney transplantation stimulates trails of live-related transplants across the ABO antibody barrier. Successful desensitization was achieved by repeated plasmapheresis with intensified immunosuppression. This study estimates the effect of serial sessions of plasma exchange on different blood group antibody titers. Patients and methods This is a pilot study that included 25 prescribed plasma exchange treatments with albumin replacement for miscellaneous indications. Patients using plasma as a replacement during sessions, positive direct and indirect antiglobulin test and AB blood group were excluded. Blood group antibody titers were measured by the gel card method before starting plasma exchange and after each session for five sessions. Results The study included a total of 25 patients, 12 (48%) had A1 blood group, eight (32%) had blood group B, and five (20%) had blood group O. The baseline anti-(A) and anti-(B) antibody titers before plasma exchange were median (interquartile range) 128.00 (192) and 64 (64) with significant reduction after five sessions with median (interquartile range) 1 (4) and 2 (1), respectively, with P value less than 0.001. Anti-(A) and anti-(B) antibody titer percent reduction from baseline to fifth session were mean±SD=99.04 ± 0.72 and =97.93 ± 0.99%, respectively. Anti-(A) and anti-(B) antibody titers were negatively correlated with patient's age (r=0.731, P=0.005; r=0.793, P<0.001, respectively). Patients with age less than 50 (n=13) years have higher anti-(A) and anti-(B) antibodies compared with patients with age more than 50 years (N=12) with P value less than 0.001. Also, on comparing patients on immunosuppressive drugs with patients not on immunosuppressive drugs as regards baseline antibody titers before exchange sessions and after five plasma exchange sessions, there was no significant difference in anti-(B) while anti-(A) titer was higher in patients without immunosuppressive drugs with P valueless than 0.05 and on fifth session, P value of 0.01. Conclusion Serial plasma exchange sessions with albumin replacement is an effective method for ABO antibody titer reduction. Baseline titers seem to be affected by age and adjuvant immunosuppressive therapy.