Diagnostic criteria of antibody-mediated rejection in kidney transplants.

The diagnosis and treatment of anti-donor antibody-mediated rejection or humoral rejection (ABMR) is one of the main discussions at the moment in kidney transplantation. The search for histopathological markers that help us to diagnose ABMR has been more problematic, in contrast to the histological expression of cellular or tubulointerstitial rejection. Although the relationship between post-transplant anti-donor antibodies and the allograft's prognosis has been a topic of discussion for a long time, led in the main by P.Terasaki, it was not until the beginning of 1990s when P. Halloran studied the humoral mechanisms of rejection in greater depth. Feutch described the importance of C4d deposits as a marker that shows a humoral mechanism of allograft rejection in 1993. As a result of many studies carried out, the Banff consensus group established some diagnostic histopathological criteria of acute (ABMR) in 2003. These have been modified slightly in later meetings of the group. Furthermore, in 2005 this same working group looked at the physiopathological mechanisms causing chronic allograft failure in more detail and established the criteria defining chronic humoral rejection. In this review, we are trying to update any useful histopathological criteria for diagnosing acute and chronic ABMR.