Renal allograft failure resulting from diffuse cortical necrosis.

Cortical necrosis of the renal allograft is an extremely rare but serious complication of renal transplantation and can lead to graft failure. Few cases have been reported in the literature to date. We present a rare case of a 28-year-old woman with chronic kidney disease for the past four years who was on biweekly hemodialysis and referred to our tertiary care center for a living-related renal transplant. The patient developed tacrolimus toxicity on the second day post-transplant. The renal biopsy performed on third day after transplant showed ischemic acute tubular injury. C4d and donor-specific antibodies were negative. On day 12 post-transplant, USG Doppler of the renal allograft showed thrombosis of the renal vein, and an open wedge biopsy was performed that showed extensive renal cortical necrosis. A month and half later, the patient developed pus collection anterior to the transplanted kidney and a fistula from the perinephric space up to the skin with persistent pus discharge. Two months later, a graft nephrectomy was performed, and diffuse cortical necrosis of renal allograft with a thick band of exudate on the capsule was diagnosed on histopathology. Ureteral necrosis and thrombosis of both renal artery and renal vein were also seen. In this case, the etiology of graft cortical necrosis is multifactorial and includes acute ischemia, urologic complications, and sepsis. To prevent graft failures, it is critical to differentiate thrombosis caused by surgical complications from hyperacute or acute humoral rejection.