Severe acute‐hybrid rejection occurring nine months after kidney transplantation: a report of rescue by orchestration of antirejection therapies

  Although a majority of acute rejection (AR) in non‐sensitized recipients is T‐cell‐mediated by primed T cells, recent studies have shown that antibody‐mediated acute rejection occurs in 20–30% of AR, and that it is often refractory to conventional antirejection therapy; possibly leading to graft loss. We report a case of severe acute‐hybrid rejection consisting of both features in a non‐sensitized kidney recipient, which was rescued by the orchestration of antirejection therapies. A 33‐yr‐old Japanese male, with advanced‐stage chronic kidney disease with an unknown etiology, underwent a HLA 3/6 mismatch and ABO‐compatible living‐related kidney transplantation preemptively. He had an excellent clinical course, except for initial cytomegalovirus infection, with good graft function [serum creatinine (sCr) 1.1 mg/dL]. Nine months later, his creatinine abruptly increased to 2.1 mg/dL, when graft biopsy revealed acute T cell‐mediated rejection (ATMR) grade IA, and simultaneous acute antibody‐mediated rejection (AAMR) grade I. Antirejeciton therapy, comprising methyl‐prednisolone pulse and 15‐deoxyspergualin, and second line rituximab and plasmapheresis, was ineffective. Moreover, histologically and clinically, the rejection status deteriorated (ATMR grade III and AAMR grade III, max sCr 4.0 mg/dL). Next, we administered muromonab CD3 and basiliximab, which could eradicate the complicated severe AR without opportunistic infection, even under the strong immunosuppression. The present case implies that high‐grade combined rejection can respond to anti‐CD 20 and anti‐CD25 mAbs, without serious complication; however, post‐operative, thorough appropriate monitoring of immunosuppression is important because its effects are limited.