Late and early C4d-positive acute rejection: different clinico-histopathological subentities in renal transplantation

This study was performed to investigate the clinical and pathologic features of C4d-positive steroid-resistant acute rejection (AR) at different phases after renal transplantation. Fifty-six kidney allograft recipients with C4d-positive AR were divided into three groups, very early rejection (VER, occurring ≤14 days following transplantation, n=28), early rejection (ER, occurring 15–180 days following transplantation, n=5), and late rejection (LR, occurring >180 days following transplantation, n=23). Clinical and pathological features were evaluated. Significantly more patients in the ER and LR groups were associated with a reduction or withdrawal of immunosuppressants. More patients in the ER and LR groups experienced a significant (>3 g/l) decrease in serum albumin (80% ER, 91.3% LR, 7.1% VER, P1 g/dl) (80, 100 vs 17.9%, P