Transplant girl's blood type changes!

That makes a heck of difference, don't you think?

Not really. To give a simplistic example...let's say that someone goes out and drinks some windshield wiper fluid, and not knowing that it's toxic, continues to party with his friends, downing copious quanitities of alcohol, and survives the episode. Just because it is unusual for people who poison themselves with methanol to recover without emergency treatment, and if ethanol (as a treatment for methanol poisoning) is used it is given intravenously and under carefully monitored conditions, doesn't mean that his recovery was unprecedented or mysterious.

If her body was able to do this on its own without any other kind of transplanted cells, and that's never been seen before, to my mind, that makes her unique.

My point is that all of the processes that took place in this girl have been seen before.

I imagine her surgeons probably want to figure out why.

Then you don't know surgeons. ;)

(sorry, couldn't resist a dig at surgeons)

Linda
 

I realize that you're probably just trying to be a smart-ass ;), but I was attempting to make clear that what was unique about the case was not the processes - all of which have been previously recognized - but just the way in which the combination of all these processes led to a particular outcome that is usually reached through a different chain of events (or rather, is not usually attempted). It's sorta like saying, "this case is unique because this was the first redhead who was transplanted".

Linda
 
If her body was able to do this on its own without any other kind of transplanted cells, and that's never been seen before, to my mind, that makes her unique.

To elaborate on this a bit...

Full engraftment of the bone marrow is seen when an adequate dose of hematopoietic cells are given. Normally liver transplantation does not provide an adequate dose, but the younger liver in this case just happened to provide an adequate dose.

Chimerism does not usually persist, or persists at a lower level in liver transplant because the immune system is usually intact when the transplant is done. However, in her case, her immune system was not intact due to the illness which led to her liver failure and to a second illness due to CMV.

Linda
 
Then you don't know surgeons. ;)

(sorry, couldn't resist a dig at surgeons)

Linda

My uncle, who is a pediatrician, says that if you want to hide something from a surgeon, just put it in a book.

:D
 
fls, can you please get in contact with the doctors at Sydney's children's hospital - they have no explanation for what happened, so sort them out, will you.
 
fls, can you please get in contact with the doctors at Sydney's children's hospital - they have no explanation for what happened, so sort them out, will you.

Well, if they have no explanation, they sure did an excellent job of hiding it by providing a detailed explanation in the NEJM report.

This is a good example of how the lay press rarely manages to convey the essence of science story.

Linda
 
Well, if they have no explanation, they sure did an excellent job of hiding it by providing a detailed explanation in the NEJM report.

This is a good example of how the lay press rarely manages to convey the essence of science story.

Linda

Haha, this is the exact same rant I was having to my wife the other night. The news was using the same old sensationalist words of 'baffled' and 'miraculous', and yet the paper I read that day seemed to have it fairly well covered. Sure, the exact mechanisms of what made it occur in this situation and not others hasn't been described, but the process itself is fairly straight forward.

Athon
 
fls You speak as if you are an authority on the subject. What are your qualifications and experience?

I do expect you do have such things. A person like me would not be able to give such answers as you have. Specifying the above would then complete your post.
 
Well, if they have no explanation, they sure did an excellent job of hiding it by providing a detailed explanation in the NEJM report.

Ah, I'll take that as a "no" then. Either that or you're being deliberately obtuse in trying to conflate the facts about the process of the change with the points that it's: A) unique, and B) the doctors have no idea why it has happened. You're attempting to explain a UFO sighting by saying, "a blue light appeared in the sky". That's very helpful in re-stating the obvious, but of little benefit in why a case is unique and in this one, what it might mean for medicine.

This is a good example of how the lay press rarely manages to convey the essence of science story.

Linda

Precisely why I quoted the paediatric oncologist at Sydney Children's.
 
fls You speak as if you are an authority on the subject. What are your qualifications and experience?

I share/have shared work with my husband (patient care, research, handy-dandy proofreader for presentations :)) who specializes in liver transplant. I specialize in internal medicine.

Linda
 
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Ah, I'll take that as a "no" then. Either that or you're being deliberately obtuse in trying to conflate the facts about the process of the change with the points that it's: A) unique, and B) the doctors have no idea why it has happened. You're attempting to explain a UFO sighting by saying, "a blue light appeared in the sky". That's very helpful in re-stating the obvious, but of little benefit in why a case is unique and in this one, what it might mean for medicine.

I am sincerely trying to explain this in a way that makes sense to you. Can you specify what you think it is that is unexplained in this case and what you didn't understand about the explanation I provided earlier for what made this case unique and what it means for medicine?

Precisely why I quoted the paediatric oncologist at Sydney Children's.

The problem is that you didn't. You provided a link to an article written by a reporter that includes a few words attributed as quotes from some doctors that may differ from the exact words that the doctors used in a way that the reporter failed to realize was important and may have been taken out of context.

The research report does not suffer from those problems.

Linda
 
I am sincerely trying to explain this in a way that makes sense to you.

Nope, I'm going with you being deliberately obtuse, but that's fine.

Can you specify what you think it is that is unexplained in this case and what you didn't understand about the explanation I provided earlier for what made this case unique and what it means for medicine?

What you wrote was a precis of what the NEJM said, so thanks for that, but you're still avoiding the fact that you've made claims which you just aren't backing up.

This is the first time that a permanent change has happened after a liver transplant. That makes it unique. "Unique" = once, only, one of a kind.

Doctors have no idea why it has happened.

That is what I've been trying to convey - if you're able to refute either or both of those statements, please do so.

Again, you're claiming to know what happened while only managing to parrot the details already provided, while trying to blame journalists' ignorance for making a story out of it.

The problem is that you didn't. You provided a link to an article written by a reporter that includes a few words attributed as quotes from some doctors that may differ from the exact words that the doctors used in a way that the reporter failed to realize was important and may have been taken out of context.

The research report does not suffer from those problems.

Linda

Well, the quote could possibly out of context, but I'd be interested to know what kind of context this could have been taken from where it would mean anything other than what it purports to:

"There was no precedent for this having happened at any other time, so we were sort of flying by the seat of our pants," Michael Stormon*, a paediatric hepatologist, said.

(bolding mine)

No precedent......ever. Tautologically unequivocal even.

Obviously, you're in possession of facts that Michael Stormon isn't, so I think it would be great if you'd share your knowledge with him.

*My mistake, I called him an oncologist, while he's actually a hepatologist. Probably more useful that he's a hepatologist anyway.
 
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Nope, I'm going with you being deliberately obtuse, but that's fine.

I do a much better job when I'm deliberate. :)

What you wrote was a precis of what the NEJM said, so thanks for that, but you're still avoiding the fact that you've made claims which you just aren't backing up.

I'm not quite sure what you are referring to. I've given information about the various processes - are you looking for a resource for this information?

This is the first time that a permanent change has happened after a liver transplant. That makes it unique. "Unique" = once, only, one of a kind.

I agree that it is reasonable to refer to this case as unique. I thought it would be useful to also be specific about what makes it unique.

Doctors have no idea why it has happened.

That still doesn't help me. You want to characterize our knowledge on this case as "no plausible theories", "no explanation", and "no idea why it has happened". I got that. What I need is for you to elaborate on why you do not consider something like:

"In this patient, the profound lymphopenia at presentation and in the subsequent months after transplantation, plus the immunosuppressive effects of drugs such as tacrolimus, azathioprine, and ganciclovir, may have contributed to the engraftment of donor hematopoietic stem cells."

an explanation, idea, or plausible theory. Once I understand your perspective, I think I can clarify my position.

That is what I've been trying to convey - if you're able to refute either or both of those statements, please do so.

I'm trying to use explanation, idea, and theory in a way that I consider useful.

Again, you're claiming to know what happened while only managing to parrot the details already provided, while trying to blame journalists' ignorance for making a story out of it.

I cannot do anything other than parrot the details provided in the report, since that is all the information I have on this case. I'm not claiming to know what happened. I'm trying to convey the explanations provided by the authors in the report and trying to elaborate a bit on those processes that I am already familiar with. I wouldn't expect the journalist to be able to do either.

Well, the quote could possibly out of context, but I'd be interested to know what kind of context this could have been taken from where it would mean anything other than what it purports to:

(bolding mine)

No precedent......ever. Tautologically unequivocal even.

It looks to me like they are referring to treating a hemolytic anemia that developed in a child as a result of host-versus-graft disease due to mixed hematopoietic chimerism post liver transplant. And it is reasonable to characterize this as "flying by the seat of our pants" and "unprecedented" because, while they were able to investigate and form plausible ideas about the cause of her hemolytic anemia and by understanding the mechanism and the various ways that this sort of process can be treated propose several treatment plans, this particular situation hadn't been encountered previously. This sort of thing happens quite a bit in medicine.

Obviously, you're in possession of facts that Michael Stormon isn't, so I think it would be great if you'd share your knowledge with him.

I just think that it's quite a bit clearer to me which facts Michael Stormon is in possession of.

Linda
 
I'm more interested in the follow-up to see if her blood type reverts back to her original blood type. You have to remember, bone marrow is only one region for erythropoeisis. There are many other organs, under stress, that are capable of producing new blood cells - even in the physiologically mature individual. This all may represent a transient phenomemenon.

I've massively transfused trauma patients who's blood type has "changed" as a result, but this doesn't mean that a chimerism has occurred. I know this is a different scenario, but you can't discount native DNA in erythropoeitic organs other than bone marrow. In other words, the jury is still out for me. It may take some time - years even - but follow-up should occur on this young lady to see if she actually reverts.

-Dr. Imago
 
I'm more interested in the follow-up to see if her blood type reverts back to her original blood type. You have to remember, bone marrow is only one region for erythropoeisis. There are many other organs, under stress, that are capable of producing new blood cells - even in the physiologically mature individual. This all may represent a transient phenomemenon.

I've massively transfused trauma patients who's blood type has "changed" as a result, but this doesn't mean that a chimerism has occurred. I know this is a different scenario, but you can't discount native DNA in erythropoeitic organs other than bone marrow. In other words, the jury is still out for me. It may take some time - years even - but follow-up should occur on this young lady to see if she actually reverts.

-Dr. Imago

It has been 4 years now since this happened. Follow-up tests have shown conversion of the blood to the donor's HLA-type. She also lost antibody responses that she had had previously (i.e. MMR) and required revaccination. Current tests on T-cells are consistent with peripheral engraftment rather than just peripheral expansion of bone marrow engraftment. It looks pretty real.

Linda
 
It has been 4 years now since this happened. Follow-up tests have shown conversion of the blood to the donor's HLA-type. She also lost antibody responses that she had had previously (i.e. MMR) and required revaccination. Current tests on T-cells are consistent with peripheral engraftment rather than just peripheral expansion of bone marrow engraftment. It looks pretty real.

Linda

Okay, fair enough. I'm still trying to understand what is so special about this case, though. In autologous BMT (something you probably know more about than I do, Linda), patients own marrow is removed from the body and then otherwise-lethal chemo/XRT is given. The marrow is spun, treated, and given back to the patient. This is, in effect, a re-engraftment of the patient's native erythropoeitic system. I just don't see why this couldn't be accomplished, similarly, with a heterogenous graft.

In other words, I'm having trouble understanding the "big deal" in this, as well as the long-term ramifications. And, I wonder what would/will happen if her system kicks back into extramedullary hematopoeisis.

-Dr. Imago
 
Amazing business.

I see that no plausible theories have come up yet.

I know one that's mathematically invalid now: God.

If the moment of conception involves en-soul-ification, then what happens to the extra soul when the two distinct, en-soul-ed clusters of cells merge and form a single being?
 
I know one that's mathematically invalid now: God.

I'm waiting for the first fundy site to claim "goddidit". Has to happen.

If the moment of conception involves en-soul-ification, then what happens to the extra soul when the two distinct, en-soul-ed clusters of cells merge and form a single being?

Nah, there's only ever one; you're incorrectly conflating the "moment of conception" as it envisaged by science and christianity, independently. The argument is identical to people who start off with: "The sun doesn't rise, the earth...."

(whatever that has to do with anything)
 
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