Korean J Transplant.  2023 Nov;37(Suppl 1):S146. 10.4285/ATW2023.F-7325.

The landscape of indication biopsy results by biopsy timing and the corresponding prognosis of transplanted kidneys

• Chae SY
• Lee H
• Kim CD
• Lee SH
• Yang CW
• Chung BH

• KMID: 2551766
• DOI: http://doi.org/10.4285/ATW2023.F-7325

Abstract

Background
We conducted a retrospective multicenter study to investigate the results of clinically indicated graft kidney biopsies and subsequent graft outcomes.
Methods
We included a total of 414 patients who underwent indication biopsy for the transplanted kidney during the study period. The study aimed to examine the timing of the biopsy after transplantation, the histological findings, and the loss of graft function.
Results
We examined the distribution of histological findings in graft kidneys from the time of kidney transplantation to the time of indication biopsy. Within 1 year posttransplantation, the most common finding among rejections was acute T cell-mediated rejection (TCMR), but chronic antibody-mediated rejection (ABMR) and relapsing glomerulonephritis (GN) predominated after 1 year. Out of 398 patients, excluding those lost to follow-up, approximately 37.2% experienced graft failure. Among patients maintaining graft function, acute TCMR was most prevalent where rejection was identified. Conversely, in those losing graft function, acute TCMR (27.7%) was followed by relapsing GN (18.9%) and chronic ABMR (16.2%). Among relapsing GN cases, 54.9% lost graft function during the study, demonstrating the highest failure rate compared to other histological outcomes. Immunoglobulin A nephropathy was most common among GN, followed by focal glomerular segmental sclerosis and membranous glomerulonephritis.
Conclusions
This study revealed that chronic ABMR and relapsing GN should be the primary considerations in indication biopsies performed after 1 year posttransplantation. Additionally, a result of relapsing GN in the biopsy may indicate the greatest risk of losing graft function.