Differential Diagnosis for Graft Failure

The clinical presentation of a grossly mottled and cyanotic allograft with capsular bulging due to marked edema, followed by graft rupture, suggests a severe and immediate reaction to the transplanted kidney. The differential diagnosis can be categorized as follows:

• Single most likely diagnosis

  • B. Presence of antibodies directed toward donor ABO blood group antigens: This condition, known as acute antibody-mediated rejection (AMR), occurs when pre-formed antibodies against the donor's ABO blood group or HLA antigens are present in the recipient. The immediate reaction can cause thrombosis, edema, and necrosis of the graft, leading to its failure. The description of the graft becoming mottled, cyanotic, and eventually rupturing is consistent with the severe vascular injury seen in AMR.

• Other Likely diagnoses

  • D. Sensitized T cells to donor antigens: This refers to cellular rejection, where T cells recognize the donor kidney as foreign and mount an immune response against it. While this is a common cause of graft rejection, the immediate and severe nature of the reaction described suggests an antibody-mediated process.
  • A. Acute thrombosis of the renal vein: Thrombosis can occur due to various reasons including hypercoagulability, surgical technique, or rejection. It could lead to graft swelling and failure but might not fully explain the immediate onset and severity of the symptoms without other predisposing factors.

• Do Not Miss (ddxs that may not be likely, but would be deadly if missed.)

  • E. Stenosis or kinking of the renal artery: Although less likely given the description of the graft's appearance and the context of an immediate post-transplant setting, vascular complications such as stenosis or kinking of the renal artery can lead to ischemia and graft failure. Missing this diagnosis could result in unnecessary immunosuppressive treatment escalation rather than addressing the vascular issue.
  • C. Presence of recipient HLA class I antigens: While HLA mismatch is a risk factor for rejection, the immediate and severe reaction described is more suggestive of an ABO incompatibility or other pre-formed antibody issues rather than HLA class I antigen mismatch alone.

• Rare diagnoses

  • Other rare causes could include hyperacute rejection due to other pre-formed antibodies (e.g., against endothelial cells), but these would be less common than the ABO incompatibility issue in the context provided. Additionally, technical issues during surgery that are not immediately apparent could also lead to graft failure, but these would typically be identified and addressed during the procedure.