To investigate the effects of double plasma exchange (DFPP) and plasma exchange (PE) on the clearance efficiency of blood group antibodies, and long-term therapeutic outcomes in the recipients of ABO-incompatible living donor kidney transplantation (ABOi-LDKT).

A retrospective analysis was conducted on clinical data of 14 ABOi-LDKT recipients who underwent sole PE pretreatment and 18 ABOi-kidney transplant recipients who underwent sole DFPP pretreatment at the First Hospital of Jilin University from March 2021 to September 2023. Both groups received regular follow-up for 12 months, and the clearance efficiency of blood group antibodies, incidence of adverse reactions during plasma pretreatment, levels of IgG and IgM blood group antibodies, renal function, coagulation indicators, acute antibody-mediated rejection (AMR), and infection rates were analyzed.

The PE group and DFPP group underwent 39 and 51 plasma pretreatments, respectively, with no severe complications occurring after transplantation. Compared with the DFPP group, the PE group had a shorter single treatment duration but higher single plasma consumption. The DFPP group outperformed the PE group in terms of single plasma pre-processing volume and body weight-corrected single plasma pre-processing volume, with statistically significant differences (Z=-5.006, t=45.64, -26.16, and -9.16, all P<0.05). The titers of IgG and IgM in both groups were markedly reduced after plasma pretreatment, IgG clearance efficiencies of the PE group and the DFPP group were 0.62±0.14 and 1.08±0.67, respectively, and IgM clearance efficiencies were 1.05±0.47 and 1.23±0.75, with no statistically significant differences (all P>0.05). The incidence of adverse reactions in the PE and DFPP groups was 42.9% (6/14) and 44.4% (8/18), respectively (P>0.05). No significant difference in coagulation parameters was observed between the PE and DFPP groups before plasma pretreatment; however, significant differences emerged at transplantation. The levels of serum creatinine and estimated glomerular filtration rate showed no statistically significant differences between the two groups of recipients before plasma pretreatment and at various time points after transplantation. Within 12 months post-transplantation, two cases of AMR occurred in the PE group, while no cases were observed in the DFPP group, and the infection rates in the PE group and DFPP group were 42.9% (6/14) and 33.3% (6/18), respectively (P>0.05).

Both DFPP and PE pre-treatment significantly reduced blood group antibody titers in ABOi-LDKT recipients, with long-term improvements in blood creatinine and glomerular filtration rate. However, the DFPP group exhibited more significant impacts on coagulation indicators. Supplementing fibrinogen and monitoring coagulation function can further ensure the safety of transplantation.