Are relatives the best living liver donors?

From the Guidelines

Relatives are generally considered the best living liver donors due to their genetic similarity, which can lead to better long-term outcomes for the recipient and reduce the risk of rejection after transplantation. The evaluation process for any potential donor includes comprehensive medical testing to assess liver health, blood type compatibility, and overall physical and psychological fitness 1. For living liver donation, typically 40-60% of the donor's liver is removed, with both the donor's and recipient's portions regenerating to normal size within 8-12 weeks. Recovery for donors usually takes 8-12 weeks, with most returning to normal activities within 3-6 months.

Key Considerations

• Close biological relatives, particularly siblings, parents, and children, often provide the best match in terms of blood type compatibility and tissue matching, which reduces the risk of rejection after transplantation 1.
• Non-relatives can also be suitable donors if they are compatible, and the most important factors are compatibility, donor health, and willingness to undergo the procedure 1.
• The risks and benefits of living donor liver transplantation (LDLT) should take into account both donor and recipient, a concept known as double equipoise 1.

Donor Evaluation

The potential donor will require additional assessments that include psychological assessment and social support systems 1. If the potential recipient has an inherited metabolic disease, the feasibility of a parent wishing to serve as an LRLT donor should be determined in the context of the child’s genetic condition 1.

Outcomes

Pediatric patients with acute liver failure who received LDLT had decreased wait times to LT, decreased cold ischemia time, and improved survival compared to a group who received a cadaveric donation 1. However, some studies have suggested a higher risk of tumour recurrence with the use of partial grafts from living relatives versus whole grafts from deceased donors 1.

From the Research

Relatives as Living Liver Donors

• Relatives can be considered as potential living liver donors, with studies showing that living-related liver transplantation can have similar patient and graft outcomes compared to deceased donor transplantation 2.
• The decision to donate is often made by the donors themselves, with the major reason being "to save the lives of family members and relatives" 3.
• Living-donor liver transplantation between identical twins has been successfully performed without the use of immunosuppression, highlighting the potential benefits of syngeneic transplantation 4.

Advantages of Living-Related Liver Transplantation

• Timely access to a living donor can reduce pretransplant mortality in pediatric liver transplantation 2.
• Living-related liver transplantation may provide better posttransplant outcomes, with lower rates of artery thrombosis and acute rejection 2.
• The use of living donors can also allow for early immunosuppression withdrawal or minimization after liver transplantation, reducing the risk of long-term immunosuppressive drug side effects 5.

Considerations for Living Liver Donors

• Donors may experience unease about possible complications of organ donation and effects on their lives after donation, highlighting the need for precise and formal psychosocial assessment protocols 3.
• The selection and adjustment of immunosuppressive drugs should be individualized to optimally control alloreactivity while mitigating toxicities 6.
• Routine laboratory tests are not accurate enough to make a confident diagnosis of allograft rejection, and liver biopsy remains necessary to guide clinical decisions 6.