Story of girl's blood type change after liver transplant

[Guest guest]

Since we've been talking about immunosuppression so much lately...

http://news./s/afp/20080124/hl_afp/australiahealthchildrentransplant_08\

0124175631

Australian girl switched blood type

after transplant: doctorsSYDNEY (AFP) - An Australian girl spontaneously changed

blood groups and adopted her donor's immune system after a liver transplant, in

what doctors treating her said Thursday was the first known case of its type.

Demi-Lee Brennan was aged nine and seriously ill with liver failure when she

received the transplant, doctors at a top Sydney children's hospital told AFP.

Nine months later they discovered she had changed blood types and that her

immune system had switched over to that of the donor after stem cells from the

new liver migrated to her bone marrow.

She is now a healthy 15-year-old, Stormon, a hepatologist treating

her, told AFP. He said he had given several presentations on the case around the

world and had heard of none like it.

" It is extremely unusual -- in fact we don't know of any other instance in

which this happened, " Stormon told AFP from the Children's Hospital at Westmead.

" In effect she had had a bone marrow transplant. The majority of her immune

system had also switched over to that of the donor. "

An article on the case was published in Thursday's edition of the leading US

medical journal The New England Journal of Medicine.

Brennan's mother Kerrie Mills described the recovery as " miraculous " while the

patient herself told a news conference that doctors had given her life back to

her.

" I just can't thank them enough. It's like my second chance at life, " Brennan

said.

Doctors who treated Brennan are interested to know if the case could have

other applications in transplant surgery, where rejection of donor organs by the

recipient's immune system is a major hurdle.

Stormon said it appeared that Brennan may have been fortunate because a

" sequence of serendipitous events " , including a post-transplantation infection,

may have given the stem cells from her donor's liver the chance to proliferate

in the bone marrow, where blood cells develop.

The task now was to establish whether the same sort of outcome could be

replicated in other transplant patients, he said.

" The challenge for us now is to try and figure out how this occurred, "

Stormon said.

One possibility is that the series of events she experienced all weakened her

immune system enough for the stem cells to migrate to the bone marrow and

proliferate, Stormon said.

These factors include the particular type of liver failure she had, a

post-operation infection with the virus cytomegalovirus, and immunosuppressive

drugs.

" To try to replicate that is easier said than done, " Stormon said, but added

the case could still potentially be of crucial importance.

" The holy grail of transplant medicine is immuno-tolerance. She exemplifies

that this can occur. "