Abstract
Many studies have reported that protocol biopsy (PB) may help preserve kidney function in kidney transplant recipients. Early detection and treatment of subclinical rejection may reduce the incidence of chronic allograft nephropathy and graft failure. However, no consensus has been reached regarding PB effectiveness, timing, and policy. This study aimed to evaluate the protective role of routine PB performed 2 weeks and 1 year after kidney transplantation. We reviewed 854 kidney transplant recipients at the Samsung Medical Center between July 2007 and August 2017, with PBs planned at 2 weeks and 1 year after transplantation. We compared the trends in graft function, chronic kidney disease progression, new-onset chronic kidney disease, infection, and patient and graft survival between the 504 patients who underwent PB and 350 who did not undergo PB. The PB group was again divided into two groups: the single PB group (n = 207) and the double PB group (n = 297). In the PB group, the donors and recipients were significantly older and there was a greater presence of recipient diabetes mellitus and donor hypertension, donor-specific antigen, and a higher proportion of ABO-incompatible kidney transplantations. The PB group was significantly different from the no-PB group in terms of the trends in graft function (estimated glomerular filtration rate). The Kaplan-Meier curve showed that PB did not significantly improve graft survival or overall patient survival. However, in the multivariate Cox analysis, the double PB group had advantages in graft survival, chronic kidney disease progression, and new-onset chronic kidney disease. PB can play a protective role in the maintenance of kidney grafts in kidney transplant recipients.