An argument for expanding the simultaneous liver and kidney transplant criteria: Validity of the new UNOS allocation policy.
Nagai S, Safwan M, Collins K, Rizzari M, Moonka D, Brown K, Patel A, Yoshida A, and Abouljuod M. An argument for expanding the simultaneous liver and kidney transplant criteria: Validity of the new UNOS allocation policy. Am J Transplant 2017; 17:772-773.
Am J Transplant
Aim: According to the latest simultaneous liver-kidney transplant (SLK) allocation policy by UNOS, allocation of kidney is dependent on duration of low glomerular filtration rate (GFR) (Chronic kidney disease [CKD] criteria: GFR/min for >90 days and/min at registration) or sustained acute kidney injury (AKI criteria; duration of dialysis >6 weeks). Our practice has been to utilize SLK for patients who required dialysis longer than 4 weeks or those who had CKD not associated with hepatorenal syndrome. We aimed to review our indications of SLK, compare outcomes between SLK and liver transplant alone (LTA) in patients with renal dysfunction, and assess validity of the new UNOS SLK policy.
Methods: We retrospectively reviewed 532 primary deceased donor LT patients from 2009 to 2015. SLK patients and LTA patients who met the new CKD criteria were evaluated. Graft survival, post-transplant dialysis requirement, and recovery of kidney function were set as endpoints and compared between the groups.
Results: 44 patients underwent SLK, of whom 21 met the AKI criteria while 17 met the CKD criteria. Six SLK patients (14%) did not meet either of the AKI or CKD criteria. 72 patients with GFR <30mL/min underwent LTA; of whom 27 met the CKD criteria (LTA-CKD group). The new UNOS SLK criteria would have increased SLK by 47% (44 to 65 cases, [44-6+27]/44=1.47) and raised it in the entire liver transplant cohort by 4% (21/532). The LTA-CKD group showed worse one-year graft survival rate, compared with the SLK group (81% vs. 93%, P=0.15). Post-transplant dialysis was required more frequently in the LTA-CKD group than the SLK (59% vs. 27%, P=0.01). Post-transplant GFR at 3, 6, and 12 months was significantly worse in the LTA-CKD group than the SLK group (46 vs. 78mL/min at 3 months [P<0.001], 49 vs. 70mL/min at 6 months [P<0.001], and 46 vs. 69mL/min at 12 months [P=0.02]). Conditional graft survival after one year was similar (P=0.8).
Conclusion: The new UNOS SLK allocation criteria will significantly increase the number of SLK's, decrease the risk of post-transplant dialysis, and potentially improve short-term outcomes in patients with marginal kidney function.