Comparison of Outcomes after Delayed Graft Function: Sirolimus-Based Versus Other Calcineurin-Inhibitor Sparing Induction Immunosuppression Regimens

BACKGROUND: Sirolimus (SRL) may increase the incidence of or prolong delayed graft function (DGF) after cadaveric renal transplantation. This study compares transplant outcomes of SRL-based induction immunosuppression (IS) with other calcineurin-inhibitor (CNI) sparing regimens in the DGF setting. METHODS: Adult cadaveric renal-transplant recipients who received transplants between January 1, 1997 and June 30, 2001 and experienced DGF (n=132) were divided into three groups by induction IS: A, depleting antibody (n=41); B, SRL (n=49); and C, neither (n=42). All recipients also received steroids and mycophenolate mofetil with delayed initiation of CNIs when good renal function returned. Patient survival, graft survival, and time to rejection within 1 year of transplantation were assessed by Kaplan-Meier analysis. One-year graft function was compared using Kruskal-Wallis and Fisher's exact tests. RESULTS: The SRL group had longer DGF duration (P=0.01). The three groups had comparable patient (P=0.27) and graft survival (P=0.69), but the depleting antibody group experienced less rejection (P=0.004). There were no clinically significant differences in 1-year graft function. CONCLUSIONS: In our analysis of a large and modern cohort of adult cadaveric transplant recipients with DGF, induction immunosuppression with a depleting antibody preparation reduced rejection, whereas SRL prolonged DGF duration. All three CNI-sparing induction IS regimens resulted in comparable patient survival, graft survival, and graft function.