Predictors of renal recovery in patients with pre-orthotopic liver transplant (OLT) renal dysfunction

BACKGROUND: Renal dysfunction occurs commonly in patients awaiting orthotopic liver transplantation (OLT) for end-stage liver disease. The use of simultaneous liver-kidney transplantation has increased in the MELD scoring era. As patients may recover renal function after OLT, identifying factors predictive of renal recovery is a critical issue, especially given the scarcity of available organs. METHODS: Employing the UNOS database, we sought to identify donor- and patient-related predictors of renal recovery among 1720 patients with pre-OLT renal dysfunction and transplanted from 1989 to 2005. Recovery of renal function post-OLT was defined as a composite endpoint of serum creatinine (SCr) ≤1.5 mg/dL at discharge and survival ≥29 days. Pre-OLT renal dysfunction was defined as any of the following: SCr ≥2 mg/dL at any time while awaiting OLT or need for renal replacement therapy (RRT) at the time of registration and/or OLT. RESULTS: Independent predictors of recovery of renal function post-OLT were absence of hepatic allograft dysfunction, transplantation during MELD era, recipient female sex, decreased donor age, decreased recipient ALT at time of OLT, decreased recipient body mass index at registration, use of anti-thymocyte globulin as induction therapy, and longer wait time from registration. Contrary to popular belief, a requirement for RRT, even for prolonged periods in excess of 8 weeks, was not an independent predictor of failure to recover renal function post-OLT. CONCLUSION: These data indicate that the duration of renal dysfunction, even among those requiring RRT, is a poor way to discriminate reversible from irreversible renal dysfunction.