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SYDNEY - A young Australian transplant patient has defied modern medical doctrine by spontaneously switching blood types and taking on her donor's immune system.
New South Wales teenager Demi Brennan is believed to be the first person in the world to completely accept a donated organ to the extent where her immune system entirely changed.
Demi, now 15, suffered liver failure and had a liver transplant at the age of nine in 2001. Several months on from the transplant, her doctors at Westmead Children's Hospital were shocked to discover her blood type had changed to match the blood type of her deceased male donor.
On closer inspection, specialists found that stem cells from the donor liver had penetrated her bone marrow, effectively resulting in a naturally-occurring bone marrow transplant.
Her treating doctor Michael Stormon said she was able to come off the immunosuppressant drugs that most transplant patients needed to take life-long to ensure they don't reject the donated organ.
"We were stunned, absolutely stunned, and also very puzzled," said Dr Stormon, who reported the novel case in the New England Journal of Medicine.
"Even going through the literature and seeking advice internationally we weren't able to find any other cases like it."
Demi's mother, Kerrie Mills, describes it as "miraculous", and Dr Stormon agreed it was "still highly difficult to explain at this stage".
"We're not sure the reasons behind why this has happened but it may be that a complex range of circumstances have aligned to bring it about," he said.
"Now the task is to find out what those are so we can replicate them and allow other transplant patients to has such a complete acceptance."
A team of scientists has started research into why this rare phenomenon occurred, with hopes their findings will improve treatments and outcomes for other transplant patients.
- AAP
