Review Question - QID 100473

The patient presents with acute rejection of her transplanted organ. This process contains elements of Type II and IV hypersensitivity reactions mediated by recipient T lymphocytes and antibodies which are NOT preformed.

The patient described above presents with the typical manifestations of acute kidney transplant rejection, which can present days to months following transplantation and is marked by the presence of endothelitis mediated by mononuclear cells. The three main forms of transplant rejection are hyperacute, acute, and chronic. Hyperacute rejection is a type II hypersensitivity reaction of preformed antibodies that manifests as vessel thrombosis very soon after implantation. Chronic rejection is an irreversible reaction with poorly characterized pathogenesis that occurs over months to years that manifests as blood vessel damage, intimal thickening, and fibrosis.

Anderson stresses the need for renal biopsies of transplanted organs both before and after renal transplantation. Renal CMV infection was not found to affect transplant rejection significantly.

Hodson et al. conclude that treatment of CMV with antiviral medications reduces CMV disease and CMV-associated mortality in solid organ transplant recipients. Treatment should be instituted on CMV positive recipients and CMV negative recipients receiving CMV positive organs.

Illustration A shows a micrograph showing acute rejection with abundance of mononuclear cells in lung tissue.

Incorrect Answers:
Answer 1: Donor T cells can be involved in graft versus host disease but are not present significantly in transplant rejection.
Answer 3: Although antibodies can be involved in acute rejection, they are created after implantation of the organ and are not preformed as they would be in hyperacute rejection.
Answer 4: Donor antibodies do not play a significant role in organ rejection.
Answer 5: Type III hypersensitivity (deposition of immune complexes) does not play a significant role in transplant rejection.