Transplant Rejection


This page is dedicated to covering the different types of transplant rejection that can occur after an organ transplant. The major types are:

  1. Hyperacute
  2. Acute
  3. Chronic 

Hyperacute transplant rejection occurs within minutes to hours of the operation. It is caused by preformed antibodies against the graft that are present in the recipients circulation. Clinically the organ will show gross molting and cyanosis. The organ will experience arterial fibrinoid necrosis and capillary thrombotic occlusion.


Acute transplant rejection occurs (usually) before 6 months. The exposure of the recipient to donor antigens will induce a combined humoral and cellular activation of naive immune cells.

  • Humoral components involve C4d deposition, neutrophilic infiltrate, and necrotizing vasculitis.
  • Cellular components involve lymphocytic infiltrate and endothelitis.

Chronic transplant rejection occurs in a time frame of months to years. It is caused by a chronic, low grade immune response that is refractory to immunosuppressants. The organ will experience vascular wall thickening and luminal narrowing. Interstitial fibrosis and atrophy will also be present.


Page Updated: 06.19.2016