Natural History, Risk Factors, and Impact of Subclinical Rejection in Kidney Transplantation

Abstract

Subclinical rejection (SCR) is defined as histologically proven acute rejection in the absence of immediate functional deterioration. We evaluated the impact of SCR in 961 prospective protocol kidney biopsies from diabetic recipients of a kidney-pancreas transplant (n=119) and one kidney transplant alone taken regularly up to 10 years after transplantation. SCR was present in 60.8%, 45.7%, 25.8%, and 17.7% of biopsies at 1, 3, 12, and greater than 12 months after transplantation. Banff scores for acute interstitial inflammation and tubulitis declined exponentially with time. SCR was predicted by prior acute cellular rejection and type of immunosuppressive therapy (PP Histologic evidence of acute rejection in the absence of clinical suspicion resulted in significant tubulointerstitial damage to transplanted kidneys and contributed to CAN.