From the Guidelines
Intestinal transplant rejection is most strongly associated with immunological factors, technical and surgical complications, patient-related factors, and infections, which can be managed through close monitoring and adherence to immunosuppressive regimens, as highlighted in studies such as 1 and 1. The risk factors for intestinal transplant rejection can be broadly categorized into several key areas.
- Immunological factors such as HLA mismatching between donor and recipient, pre-existing donor-specific antibodies, and previous sensitization through blood transfusions or pregnancies play a significant role in rejection, as noted in the context of immunosuppressive protocols 1.
- Technical and surgical complications like vascular thrombosis, ischemia-reperfusion injury, and prolonged cold ischemia time significantly increase rejection risk, underscoring the importance of meticulous surgical technique and post-operative care.
- Patient-related factors including young age, certain underlying diseases (particularly autoimmune disorders), and poor nutritional status prior to transplantation also contribute to higher rejection rates, emphasizing the need for comprehensive pre-transplant evaluation and optimization of the patient's health status.
- Infection with cytomegalovirus (CMV) or Epstein-Barr virus can trigger rejection episodes, as can medication non-adherence to immunosuppressive regimens like tacrolimus, mycophenolate mofetil, and corticosteroids, highlighting the critical role of infection control and compliance with immunosuppressive therapy in preventing rejection. The intestine's high immunogenicity due to its large lymphoid tissue content and constant exposure to environmental antigens makes it particularly susceptible to rejection compared to other solid organs, as discussed in the context of immunomodulatory strategies to enhance allograft acceptance 1. Early detection through close monitoring of clinical symptoms, endoscopic surveillance with biopsies, and blood tests for inflammatory markers is essential for managing rejection risk, as intestinal rejection can progress rapidly and lead to graft failure if not promptly treated, a challenge addressed through protocols such as those outlined in 1.
From the Research
Risk Factors for Intestinal Transplant Rejection
The risk factors for intestinal transplant rejection can be identified through various studies, including:
- A liver-free graft and high level of panel reactive antibody as significant independent risk factors 2
- Presence of donor-specific antibodies (DSA) as a risk factor for acute rejection 2, 3, 4
- Presensitization to donor human leukocyte antigens class I and/or II antigens with a detectable DSA 2
- A positive cross-match 2
- Production of newly-formed DSA following intestinal transplantation 2
- Elevated neutrophil count at rejection and increased number of rejection episodes as predictors of infection in kidney and simultaneous liver-kidney recipients 5
Donor-Specific Antibodies and Rejection
Donor-specific antibodies (DSA) play a significant role in intestinal transplant rejection, with studies showing that:
- DSA are associated with acute kidney graft rejection 3
- The presence of DSA is a risk factor for acute rejection in small bowel/multivisceral transplantation 4
- The appearance of DSA can be preformed or de novo, and is associated with severe rejection grade 4
- Reduction of DSA fluorescence intensity is clinically associated with resolution of rejection 4
Infections and Rejection
Infections are a common complication after treatment of solid-organ transplant rejection, with studies showing that: