ABO-incompatible liver transplantation using only rituximab for patients with low anti-ABO antibody titer

Backgrounds/Aims

Graft survival after ABO-incompatible (ABOi) living donor liver transplantation (LDLT) has increased due to advances in desensitization methods. We analyzed early outcomes following ABOi LDLT using only rituximab without any additional desensitization methods in recipients with low anti-ABO antibody titers (≤1:32).

Methods

Ten adult patients underwent ABOi LDLT between September 2014 and December 2016. All patients were administered a single dose of rituximab (300 mg/m²) prior to LDLT. Three patients with baseline anti-ABO titer >1:32 underwent multiple sessions of plasmapheresis to reduce titers to <1:32 (rituximab+plasmapheresis, RP). Seven patients with low anti-ABO titer (≤1:32) did not undergo plasmapheresis (rituximab-only, RO). ABO-compatible LDLT patients during the same period were included for comparison (n=22).

Results

Post-transplantation titers were significantly lower in the RO than in the RP and showed no rebound rise (POD7 1.14±0.38 vs 28.0±31.7, p=0.04), (POD30 1.26±0.45 vs 108±107, p=0.02). There were no significant differences in rejection, biliary complications and infection between groups. There were no significant differences in outcome between the RO group and ABO-compatible except for infection.

Conclusions

This study shows that recipients with low baseline anti-ABO antibody titer (≤1:32) can undergo ABOi LDLT using conventional immunosuppression and rituximab alone.

Outcomes of ABO-Incompatible Living Donor Kidney Transplantation Compared to Waiting or Deceased Donor Kidney Transplantation

INTRODUCTION

ABO-incompatible (ABOi) living donor kidney transplantation (LDKT) is considered only for patients who do not have an ABO-compatible (ABOc) LD. Therefore, a clinically practical question is whether to proceed with ABOi LDKT or remain on dialysis while waiting for ABOc deceased donor kidney transplantation (DDKT). However, this issue has not been addressed in Asian countries, where ABOi LDKT programs are more active than DDKT programs.

METHODS

A total of 426 patients underwent ABOi-LDKT between 2010 and 2020 at Seoul National University Hospital and Severance Hospital, Korea. We compared outcomes between the ABOi-LDKT and the propensity-matched control groups (waiting-list-only group, n = 1,278; waiting-list-or-ABOc-DDKT group, n = 1,278).

RESULTS

The ABOi-LDKT group showed a significantly better patient survival rate than the waiting-list-only group (p = 0.001) and the waiting-list-or-ABOc-DDKT group (p = 0.048). When the ABOi-LDKT group was categorized into a high-titer group (peak anti-ABO titer ≥1:128) and a low-titer group (peak anti-ABO titer ≤1:64), the low-titer group showed better patient survival rates than those of the waiting-list-or-ABOc-DDKT group (p = 0.046) or the waiting-list-only group (p = 0.004). In contrast, the high-titer ABOi-LDKT group showed no significant benefit in patient survival compared to the waiting-list-or-ABOc-DDKT group. Death-censored graft survival in the ABOi-LDKT group was not significantly different from that in the ABOc-DDKT group (p = 0.563).

CONCLUSION

The ABOi-LDKT group has better outcomes than the waiting-list-or-ABOc-DDKT group in a country with a long waiting time.