Blood type does not matter when transplanting organs in babies

Catherine Scott, News Writer

March 28, 2007

Thanks to new research, the littlest patients awaiting organ transplants now have a greater probability of finding a donor.

Dr Lori West, a pediatric cardiologist and the director of cardiac transplantation research at the U of A, explained that the immune system of a baby doesn’t yet produce the proper antibodies to reject the blood of another type — thereby allowing successful organ transplants of mismatched blood types. She said that babies typically start to develop antibodies at about six months, but, if the transplant is done early enough in the baby’s life, the organ is completely functional.

Normally, a person with blood type-O will produce anti-A and anti-B antibodies, which means that the patient will reject an organ from a donor with type-A or type-B blood. But West explained how, in the case of infants, their bodies will adapt to accommodate a different blood type.

“If you transplant [a] baby of blood group-O with the heart of a baby who’s blood group-B, the little baby does make anti-A antibodies, but never makes anti-B antibodies,” West said.

In infants, West has found the success rate of an organ transplant with a matching blood type to be equal to that of an organ with a mismatched blood type. However, rejection based on blood type isn’t the only worry when it comes to organ transplants.

“Even if the blood groups matched, they’d still need immune-suppression [medication] because everything else about the heart is foreign,” West explained.

According to West, there’s a wider pool of organ donors available to infants in need of organ transplantation, thanks to this discovery. During her previous work in Toronto, she said that the mortality of those waiting for hearts fell from 50 per cent to less than ten per cent after they started performing the procedure. She added that the primary motivation for the research was the imminent need for organs for babies who would otherwise die.

Infants are a very high-risk group when it comes to organ transplants. The organ has to fit in the infant’s small body, the infant must be in stable condition and the infant must already be at a hospital capable of proforming the particular transplant required in order to receive the organ on time.

“They were a very compelling group of patients to work with because they had so few options,” West affirmed.

Before, West said it was very tough to have to break it to the parents that an organ transplant is absolutely necessary for their baby, while reminding them that the probability of receiving a compatible organ was very low. But with this new type of transplant being available, parents will receive more optimistic news.

“It made all the difference in the world at being able to offer a parent the possibility of a transplant and the possibility that there is a likelihood of a donor being found for their child,” West said.

The first baby to receive an incompatible blood transplant that West worked with in 1996 is now a healthy eleven-year-old boy. West is still researching the age limit for performing these transplantations, as it’s still unknown.

Copyright © 2007 The Gateway Online, Canada.

This article posted March 31, 2007.