A case of allograft dysfunction with antibody‐mediated rejection developing 13 yr after kidney transplantation

Abstract: Antibody‐mediated rejection is an important cause of chronic allograft dysfunction. We report a case of chronic antibody‐mediated rejection 13 yr after transplantation. This patient is a 19‐yr‐old man who had renal insufficiency since infancy because of bilateral polycystic kidneys. Peritoneal dialysis was started when he was four yr old and he received a renal allograft from his mother at the age of six yr. Donor and recipient were ABO compatible and immunosuppressive treatment was started with cyclosporine, mizoribine, and methylprednisolone. No acute rejection was experienced and histological acute rejection was not proven on any subsequent protocol biopsies. Ten yr after transplantation, a protocol biopsy revealed moderate chronic allograft nephropathy and severe cyclosporine‐associated arteriolopathy. His allograft function was preserved at this time and the cyclosporine dose was tapered to 125 mg/d. His renal function gradually deteriorated starting 12 yr after transplantation. Although mizoribine was changed to mycophenolate mofetil, he required dialysis one yr later. A diagnosis of antibody‐mediated rejection was made based upon the renal biopsy findings (including C4d staining) and circulating anti‐human leukocyte antigen (HLA) antibody levels (12 yr after transplantation). We conclude that it is necessary to pay attention to antibody‐mediated rejection, even in allograft cases with good function for over 10 yr and no risk factors for the development of de novo anti‐HLA antibodies.