Factors that impact on the outcome of second renal transplants in children.

We have reviewed the incidence, demography, and outcome of children who have received a repeat transplant in the North American Pediatric Renal Transplant Cooperative Study registry. From 1987 through 1994, 3290 primary and 573 first repeat transplants were performed on North American children. Living donor grafts were used in 52% of primary and 23% of first repeat transplants. Of primary transplants, 23.7% were among children under the age of 6 years. For repeat transplants, the percentage was 15% for the same category. The percentage of 2-DR mismatches was 27% for primary and 40% for repeat transplants (P < 0.01). Graft survival rates for primary transplants at 6, 12, 24, 36, and 60 months were 88%, 85%, 80%, 76%, and 69%, respectively, compared with 81%, 77%, 71%, 64%, and 52% for repeat transplants at the same time periods (P < 0.05). For cadaver donor source transplants, graft survival rates were 83%, 79%, 74%, 69%, and 62%, compared with 79%, 74%, 68%, 60%, and 47% for the repeat transplants (P < 0.01). However, for living related repeat transplants, the rates of 88%, 86%, 81%, 78%, and 72% were not significantly different from the rates of 93%, 91%, 87%, 83%, and 76% for primary transplants. A proportional hazards model for cadaver donor source repeat transplants evaluated donor age, recipient age, race, use of T-cell induction therapy, number of HLA-DR mismatches, year of transplantation, and cold storage time. Only the use of kidneys from cadaver donors less than 6 years of age was predictive of graft failure. Graft survival rates at 12 and 24 months were 77% and 70%, respectively, for donors > 6 years of age, and 58% and 54% for donors < 6 years of age (P < 0.007). We conclude that avoiding the use of younger aged cadaver donors would assure better graft survival for repeat transplants and negate the ethical dilemma facing the issue of retransplantation.