20-Year Analysis of Kidney Transplantation: A Single Center in Japan

Background. Patient and graft survival after successful kidney transplantation (KT) have improved despite an increase in the number of challenging cases. Various factors have evolved during the long history of kidney transplantation. Methods. Between 1988 and 2012, a total of 292 living donor and 56 deceased donor KTs were performed at Niigata University Hospital. Long-term patient and graft survival and changes in background during a 20-year period in a single center were retrospectively analyzed. Results. Excellent patient survival rates of 95.1% at 20 years for living donor KT and 96.2% at 15 years for deceased donor KT were observed. Graft survival rates at 1, 5, 10, 15, and 20 years were 96.8%, 95.4%, 83.1%, 61.8%, and 56.2% in living donor KT, respectively. In contrast, graft survival rates at 1, 5, 10, and 15 years in deceased donor KT were 89.0%, 80.3%, 77.3%, and 33.8%, respectively. These survival rates have dramatically improved since 2002 (91.7% for living and 80.9% for deceased donor KT at 10 years post-transplantation). The number of elderly recipients (older than 60 years) and the percentage of grafts donated from spouses have increased. The rejection rate decreased and the cytomegalovirus antigenemia positive rate increased during the 20-year period assessed. The percentage of pre-emptive KTs progressively increased, with graft survival in this group tending to be better than non-preemptive KTs. The causes of graft loss were chronic allograft dysfunction (54.7%), acute rejection (11.1%), and malignancies (9.4%). After living donor KT, the principal predictors of graft loss were if the recipient was younger than 30 years, if the donor was older than 50 years, and if the rejection episodes occurred after living donor KT. In contrast, the only risk factor in the case of deceased donor KT occurred after transplantation from donors who were older than 50 years. Conclusions. A summary of the long-term outcome of KT over 20 years in a single center has been reported. Along with the changes in patient backgrounds, immunosuppressive drugs, and our knowledge of transplantation, patient and graft survival outcomes have also changed. Investigation into such outcomes during a different transplantation era is required to fully appreciate advances in KT.