Introduction: Recently, the outcome of ABO-incompatible living donor liver transplantation (LDLT) has improved due to preoperative desensitization with rituximab and plasma-exchange (PE). Preformed donor-specific antibody (DSA) may cause antibody-mediated rejection (AMR), which is a significant risk factor for mortality in LDLT. However, the optimal prophylaxis of AMR for patients with positive-DSA has not been established. We report two patients with high preformed DSA who successfully underwent LDLT after desensitization by rituximab.
Methods: A total of 24 patients underwent LDLT from 2007 to 2019, including 4 ABO-incompatible patients. All the patients underwent preoperative compliment-dependent cytotoxic crossmatch test (CDC), and in the case of positive CDC, flow cytometric crossmatch test (FCXM) was performed. Two patients were positive for CDC and were both strongly positive for DSA by FCXM. One patient was ABO-incompatible and had a preformed DSA. Immunosuppression therapy for patients with preformed DSA was based on the protocol for ABO-incompatible LDLT as following: rituximab 500mg three weeks before transplantation, mycophenolate mofetil (MMF) 2000 mg daily given one week before transplantation, and pre-transplant PE, while post-transplant immunosuppression consisted of tacrolimus, MMF and steroids were given as the protocol of ABO-compatible patients after LDLT. Pre-transplant PE was performed in patients with high ABO-antibody titers after rituximab administration, of whom one ABO incompatible and with preformed DSA underwent performed pre-transplant PE, but the other patient did not.
Results: AMR was not observed in any DSA-positive patients. The two patients remain well with stable graft function without any rejection episodes.
Conclusion: Preoperative rituximab administration may prevent AMR in patients with strongly positive preformed DSAs in LDLT.