Auxiliary partial orthotopic liver transplantation for Crigler-Najjar syndrome type I

Objective To determine if auxiliary partial orthotopic liver transplantatio n (APOLT) has the long-term potential to correct the underlying abnormality in Crigler-Najjar syndrome type 1 (CNS1) without the need for total liver replacement. Background Orthotopic liver transplantation has been used successfully to r eplace the defective enzyme in CNS1. Experimental studies have shown that o nly 1% to 2% of the normal hepatocyte mass is needed for bilirubin conjugat ion. If APOLT corrects the underlying metabolic abnormality, it has the adv antage of preserving the native liver, which would serve as a "safety net" should the graft fail, and there is the potential for gene therapy in the f uture with possible withdrawal of immunosuppression. Methods Seven APOLT procedures were performed in six recipients with CNS1. Median age at transplantation was 10.5 years. Six transplants were performe d as a left auxiliary liver transplant, and one was performed as a right au xiliary liver transplant. Median serum bilirubin level at transplantation w as 320 mu mol/L. All patients required 12 to 16 hours of phototherapy daily before the transplant to maintain serum bilirubin levels between 250 and 3 50 mu mol/L. Results Median serum bilirubin level was 50 mu mol/L at day 5 after the tra nsplant and 23 mu mol/L at a median follow-up of 32 months. In four childre n, early severe acute rejection developed, requiring conversion to tacrolim us; one underwent a second transplant for chronic rejection and graft atrop hy but died from lymphoproliferative disease 6 months after the second tran splant. Conclusions This report shows that APOLT is technically feasible and provid es adequate hepatocyte mass to correct the underlying metabolic abnormality in CNS1.