What do you think?

[rravkin@aol.com]

So Malcolm,

You diabolical Serologist (ha..ha..), she forwards as an A but reverses as an AB. So we have a problem with the B's. Is it spring where you are; this is when all the B's come out. I am curious to see how the resolve will distiguish between wether the forward B reaction is correct or the reverse B reaction. With the info given it would seem logical to work on both simultaneously.

[LisaM]

Thanks, McGouc, for bringing up an important point for everyone to remember about never assuming things about patients--it's one of the simplest, basic concepts in any lab situation but oftentimes gets overlooked. Get that patient history, and it'll shed lots of light on your current situation!

And yes, Malcolm is diabolical--lol! I think he's enjoying, toying with us on this one. . . . we have ways to make you fess up, Malcolm (*cues "Godfather" music*) 'ya see, I know 'dis guy, an Imma gonna give 'im a call. . . . . MWWWWAAHAAAAHAA!

(If nothing else, we'll blanket tackle you and beat you with wet noodles until you tell us the resolution!! HAHA!) We wanna know!

[Malcolm Needs ☆]

So Malcolm,

You diabolical Serologist (ha..ha..), she forwards as an A but reverses as an AB. So we have a problem with the B's. Is it spring where you are; this is when all the B's come out. I am curious to see how the resolve will distiguish between wether the forward B reaction is correct or the reverse B reaction. With the info given it would seem logical to work on both simultaneously.

Yes, I am hanging my head in shame!

Incidentally, it has just turned into Spring in the UK, but I can't really use that as a valid excuse for my stupidity!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

:redface::redface:

[Malcolm Needs ☆]

If nothing else, we'll blanket tackle you and beat you with wet noodles until you tell us the resolution!!

Now there is an offer I can't refuse!!!!!!!!!!!!!!!!!!!!!!!!!!

I will give you all the answer very soon, but skyanto, in a post on page 2 of this thread, has asked me not to give the answer until next week, and I agreed so to do, unless a lot of people object.

:):)

[adiescast]

If the incubated back type at room temperature and 4 degrees does not yield any antibody, I vote for the possible transplant (BMT, cord, or stem cell) or less likely chimera. If she is an otherwise healthy 20 year old, she is not likely to have disease induced hypogammaglobulinemia (although she could have a congenital form, I suppose). I guess at this point we are dismissing the possibility of technical error (including the possibility that someone else's plasma/serum was used for the back type or cells for the front type). If she is an AB(subgroup), we might have to adsorb and elute the anti-B (human source) to figure that out.

I look forward to hearing the answer next week.

[Dr. Pepper]

Mom was a B or AB and got an A bone marrow transplant?

[skyanto]

Hello everybody,

thanks for waiting us but it is very difficult to speak at work...

We've thought this explanations:

1- patient is A and she has little title of anti-B ( we had a similar case a few weeks ago)

*diamed NaCl card at 4°C

*50microL plasma +50 microL A1,A2,B,O red cells

*30' incubation

2-patient is AB with a weak B antigen (something like ABx or ABm )

*adsorption and elution method

*adsorption: plasma patient (with anti-B )+ donor red cells B and then elution.

*adsorption: donor plasma A (with anti- + patient red cells and then elution.

3-bone marrow transplant

-patient is AB and she has been a transplant with bone marrow or cordon cells type A

(find patient history)

4- we don't know...maybe severe immunodeficiency ; so patient is A but she hasn't antibodies...

Sorry for our english..Buen trabajo a todos

[ckcheng]

ABm, or ABel without anti-B - check B sbustance in saliva if patient is a secretor in case of ABm, or perform elution study in case of ABel.

AB patient transplanted with A donor sucessfully - check medical history.

CK Cheng, MSc, SBB(ASCP), CQA(ASQ)

Mar 17, 2010

[rravkin@aol.com]

Malcolm,

Forgive me if I am asking this question again but is this the first pregnacy or past the first pregnacy?

[Malcolm Needs ☆]

Malcolm,

Forgive me if I am asking this question again but is this the first pregnacy or past the first pregnacy?

She has had one miscarriage before (see post 11 in this thread).

:)

[Yanxia]

Transplant is a cause of discrepancy, but I have a double about wether this kind of people can get pregnant.

[Malcolm Needs ☆]

Transplant is a cause of discrepancy, but I have a double about wether this kind of people can get pregnant.

I'm not saying just yet, although I hope to post the answer later today, but, yes, Yanxia, they can.

What happens is that their eggs are harvested prior to ablation (either by total body irradiation and/or by drugs), and then fertilised in vitro, prior to implantation.

There are also cases of gift ova from, for example, sisters, mothers, etc, but, as far as I know, they cannot become pregnant by the usual method.

:D:D:D:D

[Malcolm Needs ☆]

Okay, everyone; I've left you dangling long enough.

I attach the answer, as far as we have got.

Thank you all for participating; some excellent ideas.

Malcolm

:D:D:D:D:D:D:D:D:D

What do you think.doc

[heathervaught]

Fantastic case, Malcom!

[L106]

Ditto! Good case study!

[jayinsat]

too deep for me......for now. Thanks for the education.

[Malcolm Needs ☆]

too deep for me......for now. Thanks for the education.

But it will come to make sense eventually; believe me. I never used to understand this kind of stuff either. You just pick it up as you go along.

:):)

[bmarotto]

Great case, Malcom. Thank you for sharing. You said she did not have a twin but does she have any living siblings or parents that you could get samples from?

[rravkin@aol.com]

Malcolm,

Fantastic learning experience. I hope that you are able to get another specimen.

[Malcolm Needs ☆]

Great case, Malcom. Thank you for sharing. You said she did not have a twin but does she have any living siblings or parents that you could get samples from?

Thanks for your comments.

As I say, according to the referring hospital, the lady is somewhat nervous by nature, and so, if we can prove the cause by other ways, we would rather not go down this road just yet, but if we have to do so eventually, I suppose we will.

:):):)

[LisaM]

Malcolm--can you post the answer here? I wasn't able to open your attachment. Thanks!

[Yanxia]

Me too,thanks.

[Malcolm Needs ☆]

What do you think?

What we did and what is left to do to sort it out.

The initial results showed a group A individual with the forward group, and an AB individual with the reverse group by DiaMed gel column agglutination technology (CAT).

Although this confirmed the findings of the referring Hospital Blood Transfusion Laboratory, we have no automation, and, as any manual technique has a higher chance of mistakes than automated techniques, simply because a human is involved, the first think we did was to repeat all tests from the index sample.

The results were the same.

The question at this stage was, what was the lady’s past history?

She was a White European pregnant lady (early gestation of less than 28 weeks), had one miscarriage for unknown reasons, had no twin, was healthy, had not undergone a stem cell transplant.

How were we going to “attack†the case?

We re-typed the lady’s red cells with several different clones of anti-B, in case our routine blend of clones did not react with a certain group B epitope present on her red cells.

These were all negative.

We repeated the reverse group with a pool of group B red cells (a pool, in case, once again, her own anti-B was recognising an epitope not necessarily carried on the our routine group B reverse grouping red cells) at 4oC.

These tests were also negative.

We were not much farther forward at this stage!

The likelihood was that there was a weak B antigen present. Such antigens are extremely rare in White Europeans.

We used a monoclonal anti-B to try to adsorb anti-B onto the lady’s red cells, and then used the Lui technique to try to elute any anti-B off again. Crucially, because monoclonal anti-B can actually be anti-B(A), we used both group A and group O cells as the negative controls to test the eluate. The results showed the eluate to contain anti-B, reacting 4+ with the test group B red cells and 0 with both the group A and O red cells.

The lady was, therefore, a group ABel.

Unfortunately, no saliva was submitted, and so we could not (easily) look for A and/or B soluble substances.

She could be a very weak acquired B, but the missing anti-B tends to rule this out (such individuals usually have an anti-B that reacts with normal group B individuals, but not with other individuals with acquired .

We could rule out hypergammaglobulinemia and agammaglobulinemia, because the lady was healthy, and such individuals normally suffer from either low level, or high-level chronic infections.

Pregnancy can reduce the levels of anti-A, anti-B and/or anti-A,B, but the key word here is “reduceâ€, rather than “ablateâ€.

Pregnancy can also reduce the expression of the ABO antigens, but, once again, the key word is “reduceâ€, rather than “ablateâ€. In any case, the lady’s A antigen was as strong as would be expected.

So, there remains the possibility of a micro-chimera or a genuine ABel phenotype.

Although the lady has no twin, there remains the possibility that there was actually a twin in utero that was fully absorbed in utero, that there was a twin, resulting in circulatory anastomosis, but who was dead at birth (and the lady was never told about this), or that the lady is a dispermic chimera. We did not see any mixed-field reactions, but then we did not see any mixed-field reactions with the anti-B sera used.

That notwithstanding, I am hoping to get another sample from the lady, so that this can be checked at a molecular level.

There is the possibility that the lady is a Cis-AB, as such individuals usually have a weak B antigen, but they also tend to have weakly reacting anti-B, reacting against the epitope(s) of the normal B antigen that they lack. We did not detect any anti-B.

Most likely is that the lady is a genuine ABel, but once again, this would have to be proven at a molecular level. So far as I know, there are only two molecular changes that have been reported that cause Bel. These are 641T>G, leading to a Met214Arg amino acid change in the 3-α-galactosyltransferase, or 669G>T, leading to a Glu223Asp amino acid change in the 3-α-galactosyltransferase. I warn readers though; I am no expert in this area of our work. Once again, I am hoping to get another sample from the lady, so that this can be checked at a molecular level.

Once I have the molecular results (if I can get more samples; the lady is, apparently, normally a bit “twitchyâ€, and so may refuse) I will post these.

Hope this helps!

:D:D:D:D

[LisaM]

Thanks, Malcolm!

Very interesting case (although my brain hurts, now, after reading all that!!) LOL!

[nancysorensen]

Malcolm,

I would just send this for molecular testing and in the meantime call the ABO undetermined and give group O+ or O- depending on the patient's red cell type.