OPTIONS AND OUTCOMES IN THE SENSITIZED KIDNEY RECIPIENT

M. Askar¹, J.D. Schold², B. Eghtesad¹, S.M. Flechner³, B. Kaplan⁴, L. Klingman¹, N. Zein¹, J.J. Fung⁵, T. Srinivas^6
1Transplant Center, Cleveland Clinic, Cleveland/OH/UNITED STATES OF AMERICA, ²Department Of Quantitative Health Sciences, Cleveland Clinic Foundation, Cleveland/UNITED STATES OF AMERICA, ³Glickman Urological And Kidney Institute, Cleveland Clinic Foundation, Cleveland/UNITED STATES OF AMERICA, ⁴, University of Arizona, Tucson/UNITED STATES OF AMERICA, ⁵General Surgery, Cleveland Clinic, Cleveland/OH/UNITED STATES OF AMERICA, ⁶Glickman Urological And Kidney Institute, Cleveland Clinic Foundation, Cleveland/OH/UNITED STATES OF AMERICA

Body: INTRODUCTION: A positive crossmatch in combined liver kidney transplants (CLK) is considered acceptable based on assumed immunoprotective effects conferred by the liver allograft. As recent case reports highlight humoral rejection of the kidney in CLK, we studied the impact of a positive crossmatch and sensitization on CLK outcomes. METHODS: Using data from the national SRTR registry pertaining to recipients transplanted between 1995 and 2008 we examined graft (kidney, liver) and patient survival by indication of sensitization (PRA>10%) or T-cell crossmatch (TXM) status. RESULTS: Of 3298 CLK recipients, 1,878 had TXM information, 11% had indications of positive TXM and 32% of patients had either positive TXM or PRA>10%. In univariate analyses -time to kidney (p=0.01) and liver (p<0.001) graft loss and death (p<0.001) were significantly diminished among patients with either positive TXM or PRA >10% at transplantation. In the multivariate Cox Model for time to patient death these effects were independent of donor/recipient age, primary liver diagnosis, MELD score or HLA mismatch including a significant adjusted hazard for all-cause mortality (AHR=1.24, 95% C.I. 1.08-1.43).
Further, conditional 1-year patient survival (patients with at least one year of post-transplant survival) was significantly lower among sensitized patients; 78% versus 83% in non-sensitized recipients (p=0.001). CONCLUSION: Our data underscore the relevance of a positive crossmatch and sensitization to kidney graft and overall outcomes in CLK and challenge the prevailing dogma that the liver allograft in CLK universally protects the kidney from alloantibody mediated damage. Prospective studies are critically needed to investigate allosensitization and its impact on outcomes in CLK.

Disclosure: All authors have declared no conflicts of interest.