How to Use Rituximab in ABO-Incompatible Pediatric Living Donor Liver Transplantation: A Single Center Experience.

Abstract

(Background) Previous studies have demonstrated the safety of ABO-incompatible living donor liver transplantation (LDLT) using preoperative plasmapheresis and rituximab. However, no reports have so far described the timing and dosage of rituximab administration for pediatric LDLT. The aim of this study is to determine the optimal dosage and timing of rituximab treatment in patients undergoing pediatric ABO-incompatible LDLT. (Methods) Between May 2001 and July 2013, 222 LDLTs were performed for 217 patients. Emergency LDLTs were excluded, because there was not adequate time to prepare these patients for ABO-incompatible LDLT. Those cases included 32 ABO-incompatible LDLTs in 31 patients, and 12 cases (11 patients) were administered rituximab. The anti-ABO antibody titers were reduced preoperatively by plasmapheresis in all cases who were administered rituximab. Rituximab was used from January 2004 for recipients over two years of age (first period; 375 mg/m2 two weeks before LDLT in two cases, second period; 50 mg/m2 two weeks before LDLT in two cases and third period: 200 mg/m2 three weeks before LDLT in eight cases). (Results) The ABO-incompatible LDLT recipient survival rate (87.1%) was significantly lower than that of the other recipients (97.3%) (p=0.008). Two patients who were administered 375 mg/m2 of rituximab died of Pneumocystis jiroveci pneumonia and hemophagocytic syndrome, respectively. One patient who was administered 50 mg/m2 of rituximab underwent re-transplantation due to antibody-mediated complications (intrahepatic biliary strictures). All eight patients who were administered 200 mg/m2 of rituximab survived. The mean CD20+ lymphocyte count was 0.1% at the time of LDLT and 5.4% six months after LDLT. (Conclusion) In the preoperative management of patients undergoing pediatric ABO-incompatible LDLT, the administration of 200 mg/m2 of rituximab three weeks before LDLT is optimally safe and effective.