Antibody mediated rejection due to de-novo DSA causing venous thrombosis of pancreas allograft - A case report

This case describes a 34 year old female who underwent an HLA identical living donor kidney transplant with a positive flow cytometric crossmatch (FCXM), but without any donor specific antibody (DSA). Tests to detect non-HLA antibody and autoantibody were negative. Allograft functioned well without rejection. She later received a pancreas allograft, again with a weakly positive FCXM, without DSA. After good initial graft function, she developed hyperglycemia six weeks posttransplant. Cross-sectional imaging demonstrated non-enhancing pancreas allograft with new vein thrombosis. She underwent transplant pancreatectomy, the explant pathology demonstrated changes consistent with severe acute antibody mediated rejection (AMR) causing thrombosis of the pancreas allograft. She had also developed several de-novo class-I DSAs at this time. Despite extensive testing, we could not identify a causative antibody for the initial positive FCXMs or its role in the eventual rejection of the pancreas allograft.