Abstract: Objective To compare the effect of double filtration plasmapheresis (DFPP) and plasma exchange (PE) on blood type antibody removal before ABO-incompatible kidney transplantation (ABOi-KT). Method Clinical data and antibody titers before and after each treatment of 36 recipients treated with DFPP and 27 recipients treated with PE before ABOi-KT from February 2021 to December 2023 in the First Affiliated Hospital of Zhengzhou University were collected and analysed. Results 98 and 82 times of treatment were performed in DFPP and PE group, respectively. The titers of blood type antibodies after DFPP and PE treatment were significantly lower than those before treatment (P<0.05). Both DFPP and PE showed good removal effect on high titer antibodies, and the removal effect of DFPP on IgG anti-A, IgG anti-B and IgM anti-B antibodies in group of titer ≥32 was better than that in group of titer ≤16 (P<0.05). The removal effect of PE on IgM anti-A and IgM anti-B antibodies in group of titer ≥32 was better than that in group of titer ≤16 (P<0.05). Overall, DFPP and PE showed no significant difference in the removal effect on different types of antibodies. However, both DFPP and PE showed a better removal effect on IgM antibodies in group of titer ≥32 compared with group of titer ≤16 (P<0.05), and the effect of PE was more obvious. The removal effect on anti-A antibodies in PE group was better than that in DFPP group. This advantage was mainly manifested as follows: PE had a better removal effect on IgG anti-A antibody than DFPP in group of titer ≤16 (P<0.05); PE had a better removal effect on IgM anti-A antibody than DFPP in group of titer ≥32 (P<0.05). There was no significant difference between the two methods in the removal effect on the other blood group antibodies (P>0.05). Conclusion Both DFPP and PE can significantly reduce the titer of blood type antibodies, and the two methods have a better removal effect on high titer antibodies. There was no significant difference between the two methods in the removal of antibodies of other blood groups, except that the removal efficiency of low titer IgG anti-A and high titer IgM anti-A antibodies by PE was better than that by DFPP.

Key words: Double filtration plasmapheresis, Plasma exchange, ABO incompatibility, Kidney transplantation, Antibody titer