CYCLOSPORINE DOSING AND ITS RELATIONSHIP TO OUTCOME IN PEDIATRIC RENAL-TRANSPLANTATION

The North American Pediatric Renal Transplant Cooperative Study (NAPRT CS) contains information on more than 2,000 pediatric renal transplant s performed since 1987. We reviewed the NAPRTCS database to determine the long-term trends in cyclosporine dosing for pediatric recipients o f renal transplants and to determine whether there is a relationship b etween cyclosporine doses and graft outcome. More than 90% of all pati ents in the NAPRTCS registry received cyclosporine as initial therapy, with a slightly higher percentages of cadaver donor recipients than l iving-related donor recipients. Cyclosporine doses in all patients dec reased from a median of 9 mg/kg/day at one month following transplant to 4.3 mg/kg/day at 36 months. Cyclosporine doses were generally highe r in younger patients, particularly during the first year following tr ansplantation. The relationships between cyclosporine doses and both r ejection episodes and graft losses were assessed. Between 6 months and 36 months following transplantation, patients who had first rejection episodes or lost their grafts had lower median cyclosporine doses tha n those who did not. Proportional hazards regression analysis of the r isk of having a first rejection episode more than one year after the t ransplant indicated that the cyclosporine dose was negatively correlat ed with risk of rejection (RR = 0.9, P = 0.02). We conclude that cyclo sporine doses are routinely decreased following renal transplantation in children. Lower doses of cyclosporine are associated with rejection episodes, particularly late rejections. Cyclosporine doses of pediatr ic recipients of renal transplants should not be tapered.