POSTTRANSPLANT LYMPHOPROLIFERATIVE DISORDERS IN ADULT AND PEDIATRIC RENAL TRANSPLANT PATIENTS RECEIVING TACROLIMUS-BASED IMMUNOSUPPRESSION1 RON SHAPIRO,2.3 MICHAEL NALESNIK,4 JERRY MCCAULEY,2 SHEILA FEDOREK,2 MARK L. JORDAN,5 VELMA P. SCANTLEBURY,2 AsHOK JAIN,2 CARLOS VIVAS,5 DEMETRIUS ELLIS,6 SUSANNE LOMBARDOZZI-LAl"lE,6 PARMJEET RANDHAWA,4 JAMES JOHNSTON,7 THOMAS

Between March 27, 1989 and December 31, 1997, 1316 kidney transplantations alone were performed under tacrolimus-based immunosuppression at our center. Posttransplant lymphoproliferative disorders (PTLD) developed in 25 (1.9%) cases; the incidence in adults was 1.20/c (1511217). whereas in pediatric patients it was 10.IO/c (10/99; P<.OOOl). PTLD was diagnosed 21.0±22.5 months after transplantation, 25.0±24.7 months in adults and 14.4±18.2 months in pediatric patients. Of the 4 adult cases in whom both the donor and recipient Epstein Barr virus (EBV) serologies were known, 2 (50%) were seropositive donor -> seronegative recipient. Of 7 pediatric cases in whom both the donor and recipient EBV serologies were known, 6 (860/d were EBV seropositive donor -> seronegative recipient. Acute rejection was observed before the diagnosis ofPTLD in 8 (53%) of 15 adults and 3 (30%) of 10 pediatric patients. Initial treatment of PTLD included a marked decrease or cessation of immunosuppression with concomitant ganciclovir therapy; two adults and two pediatric patients required chemotherapy_ With a mean follow-up of 24_9±30.1 months after transplantation. the 1and 5-year actuarial patient and graft survival rates in adults were 930/c and 860/c. and 80lf( and 60%, respectively. Two adults died, 3.7 and 46.2 months after transplantation, of complications related to PTLD, and 10 (including the 2 deaths) lost their allograft 3.7-84.7 months after transplantation. In children, the 1and 5-year actuarial patient and graft survival rates were 1000/, and 100'7.:, and 100% and H90/c, respectively. No child died; one child lost his allograft 41.3 months after transplantation. One child had presumed recurrent PTLD that responded to discontinuation of tacrolimus and reinitiation of antiviral therapy. The mean serum creatinine level in adults was 2.5±1.2 mg/dl. and in children. it was 1.3±0.6 mg/ dl. Under tacrolimus-based immunosuppression. PTLD is less common after renal transplantation in