In a traditional kidney transplant, the donor and recipient must have matching blood groups (ABO-compatible). However, many willing living donors — often close family members — have a different blood group from the recipient. ABO-incompatible transplant overcomes this barrier through a process called desensitization, allowing patients to receive a kidney even when blood groups do not match.
What is ABO-Incompatible Transplant?
Everyone has natural antibodies against blood groups they do not possess. For example, a person with blood group O has antibodies against A and B. In ABO-incompatible transplant, these antibodies are reduced before surgery through plasmapheresis or immunoadsorption, and medications like rituximab prevent them from rising after transplant. This makes it safe to proceed despite the blood group mismatch.
Who Qualifies for ABO-Incompatible Transplant?
ABO-incompatible transplant may be considered when:
- The only willing living donor has a different blood group
- The patient is on a long deceased-donor waiting list
- The patient has high panel-reactive antibodies (PRA) making compatible donors rare
- The patient has been sensitised through previous transplants, pregnancies, or blood transfusions
- Urgency requires proceeding without waiting for a compatible donor
The Desensitization Process
Rituximab Administration
Rituximab (MabThera) is given 2-4 weeks before transplant. It depletes B-lymphocytes that produce antibodies, reducing the risk of antibody-mediated rejection.
Plasmapheresis / Immunoadsorption
Sessions of plasmapheresis (typically 3-6) are performed before surgery to remove existing anti-A or anti-B antibodies from the blood. Target is to reduce antibody titres to 1:8 or lower.
Transplant Surgery
The transplant is performed once antibody titres are at target levels. The procedure is identical to a standard kidney transplant.
Post-Transplant Monitoring
Antibody titres are monitored closely after transplant. Additional plasmapheresis sessions may be needed if titres rise. Immunosuppressive regimen is typically more intense than standard transplants.
Medications Used
- •Rituximab — B-cell depleting antibody (given before transplant)
- •Tacrolimus — calcineurin inhibitor for immunosuppression
- •Mycophenolate mofetil — prevents immune cell proliferation
- •Corticosteroids — anti-inflammatory
- •Plasmapheresis — physical removal of antibodies
- •IVIG (Intravenous Immunoglobulin) — modulates immune response
Success Rates
Modern desensitization protocols have made ABO-incompatible transplant highly successful. Five-year graft survival rates of 80-90% are reported in major centres worldwide, which is comparable to ABO-compatible living donor transplants. The key to success is meticulous antibody monitoring and adherence to immunosuppressive therapy.
Why ABO-Incompatible Transplant Matters
In India, where deceased donor organs are scarce and waiting lists are long, ABO-incompatible transplant significantly expands the donor pool. It empowers families to proceed with transplant using a willing living donor, without being constrained by blood group compatibility. This can be life-saving for patients who would otherwise spend years on dialysis.
Consult Dr. Rajesh Goel
Dr. Rajesh Goel has extensive experience managing ABO-incompatible transplants and can guide you through the complete desensitization process.