Impact of renal failure on liver transplantation survival

Renal failure after orthotopic liver transplantation (OLT) is a common complication (ranging from 12% to 70%) associated with worse outcomes, particularly when it requires renal replacement therapy (RRT). Renal dysfunction is a common scenario among waiting list patients. It can lead to a worse prognosis after OLT, due to an increased incidence of postoperative renal failure. The aim of this study was to analyze the incidence of renal failure after OLT, its relationship to pretransplant renal dysfunction, and its impact on outcomes. We analyzed data collected prospectively from 152 consecutive OLTs in 139 patients performed by the same team from March 2003 to November 2007. Exclusion criteria for 34 cases included transplantation due to acute liver failure, combined liver-kidney transplantation, retransplantation, and patients who died up to 2 days posttransplantation. Based on creatinine clearance (CCr) calculated at the time of OLT, the 118 patients were classified in two groups: group I, normal pre-OLT renal function (CCr >= 70 mL/min) versus group II, pre-OLT renal failure (CCr < 70 mL/min). Each group was analyzed according to the development of post-OLT renal failure, being classified as subgroup A (normal renal function post-OLT), subgroup B (mild renal impairment post-OLT-serum creatinine level between 2.0 and 3.0 mg/dL or doubled basal value up to 3.0 mg/dL) versus subgroup C (severe renal impairment post-OLT-serum creatinine level : 3.0 mg/dL or utilization of RRT). The overall incidence of post-OLT renal impairment was 41.52% with RRT in 22 patients (18.64%). Group II patients showed a greater incidence of post-OLT renal failure when compared with other patients (P <.05), but without a statistical difference when compared according to RRT requirement. Comparison of average hospital stay was similar between groups I and II, and also among its subgroups (A, B, and C, respectively). There was no statistical difference in early (30-day) and 1-year survival rates between groups I and II. Comparing all subgroups for early and 1-year survival, we observed that patients who developed severe renal failure post-OLT (subgroups I-C and II-C) showed worse outcomes compared with other patients (subgroups I-A, I-B, II-A, and II-B), respectively 95.29% versus 69.69% and 86.95% versus 41.66% for early and 1-year survivals (P <.001). In conclusion, our findings suggested that patients who developed severe renal failure post-OLT, independent of pretransplant renal function, showed worse outcomes.