Effect of parental donor sex on rejection in pediatric renal transplantation: a report of the North American Pediatric Renal Transplant Cooperative Study.

Using the North American Pediatric Renal Transplant Cooperative Study (NAPRTCS) database, we performed a retrospective cohort study of 1,552 pediatric renal transplant patients who had received a graft from a biological parent to determine if parental donor sex influences the development of rejection. There were 102/675 (15.1%) graft failures in paternal grafts compared to 144/877 (16.4%) graft failures in maternal grafts. Overall graft survival (p=0.48) and time to first rejection (p>0.9) were not different in patients receiving paternal versus maternal grafts. The overall frequency of graft loss to rejection was also not different. However, maternal donation was associated with a significantly longer time to first rejection in patients less than one year of age at the time of transplantation (p=0.01). Time to first rejection was not different between maternal and paternal grafts in older recipients. In summary, the present study did not demonstrate a difference in graft survival between maternal and paternal donations, but the youngest patients may experience a longer time to first rejection with maternal donation. The number of young patients is small, however, and further data are necessary to confirm this observation.