Underutilization of A2 ABO incompatible kidney transplantation

Area of Science:

• Nephrology
• Transplantation immunology
• Organ transplantation

Background:

• ABO incompatibility poses a significant challenge for kidney transplant candidates with blood types O and B.
• A2 ABO incompatible kidney transplants may offer reduced waiting times and comparable graft survival to ABO compatible transplants.

Purpose of the Study:

• To compare death-censored graft survival between ABO compatible and A2 ABO incompatible kidney transplants.
• To evaluate the utilization and outcomes of A2 incompatible kidney transplantation.

Main Methods:

• Utilized multivariate Cox regression models with data from the United Network of Organ Sharing (UNOS) from 1997 to 2007.
• Compared death-censored graft survival between ABO blood type A recipients and O, B, and AB recipients of A2 allografts.

Main Results:

• A2 incompatible kidney transplants were underutilized, with rates remaining stable around 14.6% over the study period.
• Mean wait times for A2 incompatible kidneys were significantly shorter for O and B recipients compared to their compatible counterparts.
• Five-year graft survival rates were comparable across ABO compatible and incompatible recipients (approximately 84-86.2%).

Conclusions:

• A2 incompatible kidney transplantation is underutilized despite offering similar graft outcomes to compatible transplants.
• Expanding the consideration of A2 kidneys to all blood groups could shorten waiting times and improve access to transplantation.
• These findings suggest a potential strategy to optimize kidney allograft allocation and patient outcomes.