Copyright ©The Author(s) 2023. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Transplant. Sep 18, 2023; 13(5): 221-238
Published online Sep 18, 2023. doi: 10.5500/wjt.v13.i5.221
Evolution of human kidney allograft pathology diagnostics through 30 years of the Banff classification process
Muhammed Mubarak, Amber Raza, Rahma Rashid, Shaheera Shakeel
Muhammed Mubarak, Rahma Rashid, Shaheera Shakeel, Department of Histopathology, Sindh Institute of Urology and Transplantation, Karachi 74200, Sindh, Pakistan
Amber Raza, Department of Nephrology, Sindh Institute of Urology and Transplantation, Karachi 74200, Sindh, Pakistan
Author contributions: Mubarak M, Raza A, Rashid R and Shakeel S contributed significantly and equally to the preparation of the manuscript, including primary and final drafting; Mubarak M and Raza A conceived and designed the study, and performed the research; All authors read and approved the final manuscript.
Conflict-of-interest statement: All authors declare that they have no conflict of interest to disclose.
Open-Access: This article is an open-access article that was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution NonCommercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See:
Corresponding author: Muhammed Mubarak, MD, Professor, Department of Histopathology, Sindh Institute of Urology and Transplantation, Dewan Farooque Medical Complex, Karachi 74200, Sindh, Pakistan.
Received: April 10, 2023
Peer-review started: April 10, 2023
First decision: June 1, 2023
Revised: June 5, 2023
Accepted: June 12, 2023
Article in press: June 12, 2023
Published online: September 18, 2023

The second half of the previous century witnessed a tremendous rise in the number of clinical kidney transplants worldwide. This activity was, however, accompanied by many issues and challenges. An accurate diagnosis and appropriate management of causes of graft dysfunction were and still are, a big challenge. Kidney allograft biopsy played a vital role in addressing the above challenge. However, its interpretation was not standardized for many years until, in 1991, the Banff process was started to fill this void. Thereafter, regular Banff meetings took place every 2 years for the past 30 years. Marked changes have taken place in the interpretation of kidney allograft biopsies, diagnosis, and classification of rejection and other non-rejection pathologies from the original Banff 93 classification. This review attempts to summarize those changes for increasing the awareness and understanding of kidney allograft pathology through the eyes of the Banff process. It will interest the transplant surgeons, physicians, pathologists, and allied professionals associated with the care of kidney transplant patients.

Keywords: Banff process, Rejection, Kidney allograft biopsy, Transplant pathology, Review

Core Tip: The efforts to standardize the nomenclature, classification, and reporting of kidney allograft biopsies were initiated in 1991 by a small group of renal pathologists, transplant physicians, and surgeons at a meeting in Banff, Alberta, Canada. Thereafter, regular meetings of the now ever-expanding, multidisciplinary, and international Banff community have been held every 2 years at different places around the world to revise, update and refine the classification. Major and frequent changes have occurred in the classification over the three decades of its evolution, making it extremely complex and difficult to comprehend, particularly for beginners in the field. The classification has essentially changed from pathology-based to pathogenesis-based classification and has become clinician-friendly and treatment-friendly. This review is an attempt to summarize the changes in the classification in an easily understandable manner and describe the rationale behind these changes for easy assimilation by both neophytes and practicing renal pathologists, transplant physicians, surgeons, and other relevant stakeholders.