World Organ Donation Day 2023: How and why blood group, antigen compatibility matters for a successful transplant

This World Organ Donation Day, observed every year on August 13, experts tell us about all the factors that need to be considered for a successful match

Organ size and compatibility are assessed (Source: Getty Images/Thinkstock)

Organ compatibility between donors and recipients is an important factor in ensuring successful organ transplantation. Donor-recipient matching involves a comprehensive evaluation process to mitigate the risk of organ rejection and increase the chances of long-term graft survival. This World Organ Donation Day, observed every year on August 13, experts tell us all the factors that need to be considered for a successful match.

Why is compatibility mandatory?

Compatibility involves assessing several factors to minimise the risk of rejection and maximise the chances of a successful transplant, said Dr Sanjay Yadav, consultant, liver transplant and HPB surgery, Narayana Superspeciality Hospital, Gurugram.

What is to be considered?

According to Dr Yadav, the matching process begins by evaluating the compatibility of blood type and tissue antigens between donors and recipients. “ABO blood group compatibility is a fundamental criterion, as mismatched blood types can lead to rapid rejection of the transplanted organ,” said Dr Yadav.

The primary focus lies on several key factors, including blood type, tissue compatibility, and recipient health status, said Dr Deepak Shankar Ray, senior consultant and chief of renal transplant at R N Tagore Hospital, Kolkata. “Blood type compatibility is essential for organ transplantation. ABO blood types are categorised into four groups: A, B, AB, and O. Transplantation can generally occur between compatible types, such as A to A or AB, B to B or AB, AB to AB, and O to any blood type,” Dr Ray explained.

Additionally, tissue typing helps assess the compatibility of human leukocyte antigens (HLAs) between the donor and recipient, reducing the likelihood of immune system rejection, noted Dr Yadav.

“To further refine matching, cross-matching tests are conducted. These tests expose the recipient’s blood to the donor’s blood or cells to detect any pre-existing antibodies that could lead to rejection,” said Dr Yadav. “A negative cross-match result indicates a lower risk of rejection, enhancing the likelihood of a successful transplant,” added Dr Yadav.

Blood groups play an essential role (Source: Getty Images/Thinkstock)

What more?

Clinical factors are also considered, such as the recipient’s medical condition, urgency of transplantation, and expected post-transplant outcomes.

“Organ size and compatibility are assessed, particularly in cases of paediatric recipients, to ensure the donor organ is appropriate for the recipient’s anatomy. Organs are allocated based on factors such as medical urgency, waiting time, and geographical location, ensuring a just distribution among eligible recipients,” Dr Yadav said.

However, it’s important to note that not all factors can be perfectly matched.

In some cases, a less-than-ideal match might be considered if the potential benefits outweigh the risks of rejection, experts urge, owing to advances in immunosuppressive medications that help prevent the immune system from attacking the healthy cells.

For donors, the decision to donate is voluntary.

“Donors undergo thorough medical and psychological evaluations to ensure their own well-being, and their compatibility is then assessed with potential recipients. Potential donors should be aware of the risks and benefits of the donation process and be fully informed about the procedure and its potential impact on their health,” said Dr Yadav.