The banffclassification of kidney transplant rejection

Renal allograft biopsy evaluation is essential to determine etiology of renal allograft dysfunction. The Banffclassification is a consensus classification that provides histologic criteria for standardized reporting of renal allograft rejection and other transplant related diseases. The classification was first introduced in the year 1991, and since then the classification had multiple updates based on the evolution of pathogenetic understanding of disease. The foundation of Banffclassification is pathogenesis related tissue changes and their scoring. The chapter focusses on pathology and pathogenesis of renal allograft rejection and describe the diagnostic criteria from the most recent version, the Banffclassification 2017. We describe the pathology of all phases (acute, chronic active and chronic) of antibody -mediated rejection and T cell -mediated rejection. Updated criteria for suspicious/borderline for acute rejection are described. Evolving role of molecular diagnostics in determining renal allograft rejection is discussed. Last but not the least, the strengths and weakness of Banffclassification are outlined.