Transfusion Science

[dupe]

Blinda is a 36 years female who needs operation which she will need blood but she has "antibody card" from Red Cell Immunohaemtology department that her blood has been tested and found to have antibodies in it. the card says she has the following antibodies in her blood: Anti-C, anti-E, anti-M anti-Fya and anti-Fyb.

Question

Doctor is confused by the results. Explain to her what might have happen in this case and what conditions the patient may have which could give this results.

[Malcolm Needs ☆]

This sounds awfully like a "homework" or "examination" question.

If I can be convinced that this is not so, I will attempt an answer.

[MAGNUM]

I'm with you Malcolm, sounds toooooooo academic.

[Liz]

oh my its an open book exam......

[David Saikin]

How do you know that Liz?

oh my its an open book exam......

[dupe]

This sounds awfully like a "homework" or "examination" question.

If I can be convinced that this is not so, I will attempt an answer.

Malcolm is not a home work or examination is just that my sister was given this "antibodies card" that has this result i just want to check it because she herself does not understand it.

[Liz]

How do you know that Liz?

I don't, I meant to write "Oh my so, its an open book exam question??"

I should have added the question marks.

I did not want to wrongly accuse anyone so I was actually asking. sorry!!

By the way, I caught a spammer and Cliff deleted his post!!! hehehehe !! I discretely pointed out to his signature. I am very proud of myself :juggle:

[Liz]

Ok here goes: patients are given (not in the country I am in!!) antibody cards to present at a future admission in case they need a transfusion. The card alerts the Blood Bank that this patient has these RBC antibodies so that they pay attention when preparing blood units. (these antibodies were formed due to previous transfusion or pregnancy, I dont know about naturally). These are a lot of antibodies and Belinda is Duffy negative (resistent to malaria), what is her ethnicity?

Ok so how much did I get? and if its not an exam : speedy recovery to Belinda!

[Malcolm Needs ☆]

Okay, I am also convinced, and will also try to clarify a little.

Within the Rh Blood Group System ( a complex System that contains some 50 different antigens, some very common, some very rare) there are five major antigens; D, C, c, E and e. Your sister must lack at least two of them (C and E) (don't worry - this is VERY common). The body's immune system will recognise these antigens as foreign and will mount an immune response to them when they are introduced into the individual's body, either by a transfusion, or by a leakage of red cells from a foetus to a mother during pregnancy.

In this case, your sister's immune system has, at some time, been exposed to both the C and E antigens, and has produced both anti-C and anti-E. She can still be transfused with either C-, c+, D+, E-, e+ blood (if she is D+ herself) or C-, c+, D-, E-, e+ blood (if she is either D+ or D- herself).

The M antigen is part of the MNS Blood Group System (another complex System that also contains about 50 different antigens), and, again, there are really only 5 major antigens that are tested for regularly, M, N, S, s and U. Again, if your sister lacks one or more of these, and she has been exposed to them, either by transfusion or pregnancy, her immune system will recognise these as foreign, and may mount an immune response.

In this case, your sister must lack the M antigen, have been exposed to the M antigen, and her immune system has produced an anti-M. Anti-M is different to anti-C and anti-E, in that it is rarely clinically significant, unless it reacts strictly at 37oC (body temperature) and so, if the anti-M does not react strictly at 37oC, it is quite safe to give cross-match compatible blood, whether it be M+ or M-. Often though, to be absolutely safe, such patients will be given M- blood.

The Duffy Blood Group System contains 5 antigens; Fy(a), Fy(, Fy3, Fy5 and Fy6 (it also used to contain Fy4, but this has become redundant). Your sister must lack both Fy(a) and Fy( and, incidentally, Fy3, as she has made both anti-Fya and anti-Fyb (which probably means that she has actually made anti-Fy3 [which, at a very basic level can be thought of an anti-Fya+Fyb]).

Anti-Fy3 is often highly clinically significant, and patients with this antibody must be given Fy(a-b-) blood.

So, to sum up, your sister needs blood that is C-, E-, possibly M- and Fy(a-b-).

This particular combination of "negative" antigens is quite common within people of Black ethnicity in particular, but other ethnicities also, and so finding blood suitable for your sister should not be too difficult.

I hope that helps a little.

:handshake:handshake:handshake:handshake:handshake

[Liz]

Nice! Malcolm.

[Liz]

You should come and teach my students, you are very good and patient.

[dupe]

The ethnicity of Belinda is of African descent. Thank you malcolm and liZ you guys are fantastic more glory to your elbow good work.

Dupe.