Background: The use of antilymphocyte antibodies for induction therapy or for treatment for rejection has been associated with an increased risk of posttransplant lymphoproliferative disorder (PTLD). The authors investigated the incidence of PTLD after monoclonal antilymphocyte, polyclonal antilymphocyte, interleukin (IL)-2 receptor antibody, or no induction therapy in primary kidney transplant recipients.
Methods: A multivariate Cox analysis of 38,519 primary kidney transplants from January 1, 1997, to December 31, 2000, was performed to compare the incidence of PTLD, graft survival, and patient survival among the induction groups.
Results: The actual incidence of PTLD was 0.85% in 2,713 recipients with monoclonal, 0.81% in 4,343 with polyclonal, 0.50% in 7,800 with IL-2, and 0.51% in 23,663 recipients with no induction therapy (P=0.02). The Cox model indicated that as compared with no induction, the increased risk of PTLD was 72% with monoclonal (P=0.03), 29% with polyclonal (P=0.27), and 14% with IL-2 induction (P=0.52). IL-2 receptor antibody was associated with a 17% reduced risk of graft loss (P=0.002) and a 21% reduced risk of mortality (P=0.005) compared with no induction. Monoclonal and polyclonal induction therapies were not associated with a reduced risk of graft loss or mortality. Mycophenolate mofetil discharge maintenance immunosuppression was associated with a significantly reduced risk of PTLD and graft loss compared with azathioprine.
Conclusions: Among induction therapies, IL-2 receptor antibody induction was associated with the smallest risk of PTLD and improved graft and patient survival. Monoclonal or polyclonal induction was not associated with improved graft or patient survival, and monoclonal induction was associated with an increased risk of PTLD.