Learning Objectives:

Review the current (2017) Banff criteria for diagnosis of active and chronic activeantibody-mediated rejection (ABMR) in renal allografts.
Summarize the literature justifying key changes made from earlier versions of the Banff ABMR classification, including the inclusion of C4d-negative ABMR, threshold levels of microvascular inflammation required for diagnosis of C4d-negative ABMR, inclusion of surrogate markers for donor-specific antibodies including molecular diagnostics, and data indicating how these have improved our ability to diagnose ABMR on allograft biopsies compared to previous Banff criteria.
Identify possible weaknesses and points of confusion within the Banff 2017 criteria for ABMR, and discuss ongoing and possible future efforts to improve the classification with respect to inter-observer reproducibility and clinical relevance.

Mark Haas MD, PhD

Professor, Cedars-Sinai Professorial Series , Cedars-Sinai Medical Center