Declining outcomes in simultaneous liver-kidney transplantation in the MELD era: Ineffective usage of renal allografts

Background. When the United Network for Organ Sharing changed its algorithm for liver allocation to the model for end-stage liver disease (MELD) system in 2002, highest priority shifted to patients with renal insufficiency as a major component of their end-stage liver disease. An unintended consequence of the new system was a rapid increase in the number of simultaneous liver-kidney transplants (SLK) being performed yearly. Methods. Adult recipients of deceased donor liver transplants (LT, n= 19,137), kidney transplants (n=33,712), and SLK transplants (n= 1,032) between 1987 and 2006 were evaluated based on United Network for Organ Sharing data. Recipients were stratified by donor subgroup, MELD score, pre-versus post-MELD era, and length of time on dialysis. Matched-control analyses were performed, and graft and patient survival were analyzed by Kaplan-Meier and Cox proportional hazards analyses. Results. MELD era outcomes demonstrate a decline in patient survival after SLK: Using matched-control analysis, we are unable to demonstrate a benefit in the SLK cohort compared with LT, despite the fact that higher quality allografts are being used for SLK. Subgroup analysis of the SLK cohort did demonstrate an increase in overall 1-year patient and liver graft survival only in those patients on long-term dialysis (>= 3 months) compared with LT (84.5% vs. 70.8%, P=0.008; hazards ratio 0.57 [95% CI 0.34, 0.95], P=0.03). Conclusion. These findings suggest that SLK maybe overused in the MELD era and that current prioritization of kidney grafts to those liver failure patients results in wasting of limited resources.