ABO-Incompatible Kidney Transplants – How Kidney Transplants Are Evolving

Matching the blood groups (or blood group compatibility) is one of the primary and most crucial steps in organ donations. Conventionally, kidney transplants were carried out only if the blood groups of the donor and recipient matched.

Our bodies have naturally occurring anti-blood group antibodies, which act as a barrier and attack anything “foreign” to one’s own blood group. When a kidney from an incompatible donor is transplanted, these anti-blood group antibodies immediately initiate rejection, a phenomenon medically called hyper-acute rejection.

In recent years, there has been an alarming increase in the number of people living with chronic kidney disease (CKD), who need a kidney transplant for survival. But the availability of donor kidneys is far less than the growing demand, leaving many patients waiting for years on transplant lists. This widening gap paved the way for a medical breakthrough: blood group-incompatible (ABOi) transplantation.

Understanding ABO-Incompatible Transplantation

In simple terms, an ABO-Incompatible Transplantation is a kidney transplant between people with mismatched blood groups. Doctors follow a few crucial steps before the transplant procedure to ensure the recipient’s body is prepared to accept the donor’s kidney with reduced risk of rejection. These steps include:

Measuring the recipient’s anti-blood group antibody levels

Preparing the body about 2–3 weeks before surgery with a special immunosuppression protocol in case the antibodies are high.

Removing antibodies and reducing them to a safe level using specialized treatments like plasmapheresis or glycosorb therapy.

Once the antibody levels are lowered to a safe level, the kidney transplant is performed.

After the transplant surgery, the recipient is kept under close observation for both antibody levels and kidney function and the patient will be continued on immunosuppressant therapy. However, in most cases, routine antibody monitoring is not needed after the first month, indicating the body’s adjustment with the new kidney.

How successful are ABO-incompatible transplantations?

Available data show that ABO-incompatible kidney transplants have outcomes on par with the blood group compatible ones. For patients with ESRD, this means that a life-saving transplant does not necessarily depend on blood group compatibility. However, despite ABO-incompatible transplantations transforming lives, there are a few considerations and challenges:

There is a slightly higher risk of rejection and infections

As the procedure requires specialized therapies to reduce the risk of rejection, the procedure costs more than the blood-group compatible transplant surgeries.

In some cases, antibody levels may not reduce to the desired level despite the specialized therapies.

To summarize, Medical science is constantly striving to push boundaries to give patients with end-stage renal disease a second chance at life. The evolution of ABO-incompatible kidney transplantation is a testimony to how innovation and determination can overcome biological barriers. Although blood group compatibility is a crucial step in transplant surgeries, it no longer remains an absolute limitation. With specialized preparation therapies and expert care, even mismatched blood groups can come together to save lives. Organ donation is a powerful gift that can turn despair into hope and illness into healing, whether the blood group is matched or mismatched.

(This article is authored by Dr. Sridhar A.V.S.S.N, Consultant - Nephrologist, Manipal Hospital Vijayawada)