AUTHOR=Afrouzian Marjan , Kozakowski Nicolas , Liapis Helen , Broecker Verena , Truong Luon , Avila-Casado Carmen , Regele Heinz , Seshan Surya , Ambruzs Josephine M. , Farris Alton Brad , Buob David , Chander Praveen N. , Cheraghvandi Lukman , Clahsen-van Groningen Marian C. , de Almeida Araujo Stanley , Ertoy Baydar Dilek , Formby Mark , Galesic Ljubanovic Danica , Herrera Hernandez Loren , Honsova Eva , Mohamed Nasreen , Ozluk Yasemin , Rabant Marion , Royal Virginie , Stevenson Heather L. , Toniolo Maria Fernanda , Taheri Diana TITLE=Thrombotic Microangiopathy in the Renal Allograft: Results of the TMA Banff Working Group Consensus on Pathologic Diagnostic Criteria JOURNAL=Transplant International VOLUME=36 YEAR=2023 URL=https://www.frontierspartnerships.org/journals/transplant-international/articles/10.3389/ti.2023.11590 DOI=10.3389/ti.2023.11590 ISSN=1432-2277 ABSTRACT=

The Banff community summoned the TMA Banff Working Group to develop minimum diagnostic criteria (MDC) and recommendations for renal transplant TMA (Tx-TMA) diagnosis, which currently lacks standardized criteria. Using the Delphi method for consensus generation, 23 nephropathologists (panelists) with >3 years of diagnostic experience with Tx-TMA were asked to list light, immunofluorescence, and electron microscopic, clinical and laboratory criteria and differential diagnoses for Tx-TMA. Delphi was modified to include 2 validations rounds with histological evaluation of whole slide images of 37 transplant biopsies (28 TMA and 9 non-TMA). Starting with 338 criteria in R1, MDC were narrowed down to 24 in R8 generating 18 pathological, 2 clinical, 4 laboratory criteria, and 8 differential diagnoses. The panelists reached a good level of agreement (70%) on 76% of the validated cases. For the first time in Banff classification, Delphi was used to reach consensus on MDC for Tx-TMA. Phase I of the study (pathology phase) will be used as a model for Phase II (nephrology phase) for consensus regarding clinical and laboratory criteria. Eventually in Phase III (consensus of the consensus groups) and the final MDC for Tx-TMA will be reported to the transplantation community.