639 - Outcomes of Combined and Sequential Kidney-Liver Transplant: a single center experience.

Publication Number: 639.5745

Michelle keyser, UPMC Childrens Hospital of Pittsburgh, Pittsburgh, PA, United States; Katherine Kurzinski, UPMC Childrens Hospital of Pittsburgh, Pittsburgh, PA, United States; Simon Horslen, UPMC Children's Hospital of Pittsburgh, Pittsburgh, PA, United States; George Mazariegos, UPMC Children's Hospital of Pittsburgh, Pittsburgh, PA, United States; Armando J. Ganoza, UPMC Childrens Hospital of Pittsburgh, PITTSBURGH, PA, United States; Juhi Kumar, UPMC Childrens Hospital of Pittsburgh, Pittsburgh, PA, United States

Background: Liver and kidney transplants are performed for conditions that affect both organs such as autosomal recessive polycystic kidney disease (ARPKD), methylmalonic acidemia (MMA) and primary hyperoxaluria type 1 (PH1). Combined kidney and liver transplants (CLKT) may provide an immunological advantage of having organs from the same donor with the liver allograft thought to offer protection to the renal allograft. Sequential liver and kidney transplants (SLKT) avoid an extensive surgery but lose the potential immunological advantage of CLKT.

Objective: Evaluate outcomes of CLKT and SLKT at our center.

Design/Methods: Retrospective cohort study of CLKT and SLKT conducted between January 2003-June 2024. Cohort characteristics and outcomes such as allograft and patient survival, rejections, presence of DSA and viremias (CMV, EBV, BKV) were evaluated.

Results: We performed 23 liver and kidney transplants, of these 17 were CLKT and 6 SLKT. Causes of organ failure were 11 ARPKD, 9 MMA, 1 PH1, 2 congenital hepatic fibrosis/renal dysplasia and nephronophthisis. Median age at transplant was 9 (range 1-22 years). 52% were male. Racial distribution was: 83% White, 8.7 % each Black and Asian. Ethnicity was non-Hispanic in 96%. In the CLKT group there were 2 living and 15 deceased donor transplants. In the SLKT group all kidney transplants were after liver and were living donor. Thymoglobulin was the predominant induction therapy in 65% and Alemtuzumab in 9%. Maintenance immunosuppression was Tacrolimus and Mycophenolate mofetil in 65%; Prednisone, Tacrolimus and Mycophenolate mofetil in 17% due to early rejections and Tacrolimus monotherapy in 2%. Duration of follow-up ranged from 0.5 to 21 years. Allograft survival was 100% for liver and 94% for kidney in the CLKT cohort and 100% for both liver and kidney in the SLKT group. Patient survival was 100% for both the cohorts. In the CLKT group, liver allograft rejections were present in 8 and kidney rejections in 6 patients. Donor specific antibodies (DSA) were present in 7 patients in the CLKT group. In the SLKT group 3 patients experienced rejections in the liver and 1 in the kidney allograft. DSA were present against the liver in 2 and the kidney in 2 patients. Viremias in the CLKT group included 2 patients with CMV, 4 EBV and 3 BK and 1 CMV, 3 EBV and 1 BK in the SLKT group.

Conclusion(s): Allograft survival was excellent in our CLKT and SLKT cohorts despite rejection episodes and presence of DSA. Timing and decision making between CLKT and SLKT are critical. While early immunological advantage of CLKT over SLKT is unclear, long-term benefits requires ongoing analysis.