Malcolm Needs

Forgot to ask yesterday. Mind like a sieve. No, I was wrong. Apparently, the case I was thinking of was apheresis platelets. :redface::redface:

No, sorry, that isn't what I meant. What I meant was that the group A blood that had been transfused to the unfortunate patient appeared to have been totally cleared from his circulation (as, indeed, had most of his own red cells, as innocent bystanders to the complement cascade), as we could not detect any group A cells in the post-mortem blood sample, but, although the DAT of the post-mortem blood sample was negative, we could still elute anti-A from the few red cells that were left. The original unit that was transfused in error was most certainly a group A, and reacted normally with anti-A. Sorry for any confusion. Having said that, Apae reacts a bit like the scary phenomenon that you describe (but is most unlkely to cause an acute transfusion reaction i a group O patient.

We have just received a sample from one of our hospitals on a pregnant woman. "Antibody detected by enzyme only. ?anti-N??" Even if I'm exsanguinating, please don't send me there!!!!!!!!!!!!!!!!!!!!!!!! It was anti-Le(a+ by the way. :eek::eek:

30 pages! Goodness me, we send ours away to be bound! Bah humbug, by the way. It's not even December yet. There is still a VERY important date to come before 25th December. :mad::mad::mad:

I can see why you would be more than a little aghast at my answer Brenda (particularly concerning the cord bloods), but, as a Reference Laboratory, we only get the odd one or two sent to us, and these are usually listed as for investigation of HDNF. As a result, we are sort of "duty bound" to throw everything at them. I prefer the 1 month time limit. George Garratty and his co-workers wrote a paper concerning auto-adsorptions some time ago, and why they should not be performed on samples from patients who had been transfused within the previous three months. One of the reasons was that the transfused red cells remaining in the circulation could adsorb out a "new" alloantibody, even though there would be very few transfused red cells left. This suggests that the majority of the "new" antibody would be coating the transfused red cells, rather than be free in the plasma (although I am not suggesting that there would be no free "new" antibody in the plasma). These days, however, the elution kits are excellent, making the removal of any antibody much more efficient, and, as a result, the identification of a "new" antibody in the eluate is probably more sensitive than just examining the plasma. I see that you say that you have never performed an adsorption on an eluate. My advice is, DON'T, unless there is a very good reason, you have loads of spare time on your hands and you decide that you do not want to get out more! It is something that we would only do in extremis. :D:D:D:D

I agree with you that the Blood Bank should have a separate Quality Manual; not least, as you say yourself, because many of the other Departments only pay lip-service to GMP. At the very least, there should be a separate "chapter" in the QM devoted to BT, because it is the only Pathology Department that actually gives out a product; and a product that can kill. Within the NHSBT, there is an over arching Quality Manual, but each section and sub-section (e.g. Specialist Services and, within that, Red Cell Immunohaematology) has their own QM; and this works extremely well (and CPA love it). I'm now going for a lie down. Agreeing with you Rashmi has made me feel quite faint!!!!!!!!!!!!! :D:D:D:D

We would perform an eluate on all cord samples with a positive DAT, to make sure that the antibody sensitising the cord cells is not another antibody in the mother's plasma that we hadn't idenified. For example, in group O mum, who is R1R1, K-, and in whose plasma we had identified anti-A, anti-B (+ anti-A,, anti-c, anti-E and anti-K, there could also be, for example, an antibody directed against a low incidence antigen that is actually causing the HDN. Following transfusion, with a de novo DAT+, we would perform an eluate up to 1 month post-transfusion, even if an alloantibody is detected in the plasma, just in case there is a second antibody Lurking in the background that is not detected in the plasma. In a case of a patient with a known +DAT, we would be much more conservative, unless there was a sudden decrease in the time between the requirement for transfusion. In such cases we would perform an eluate, to see if an alloantibody could be identified that reacts more strongly than the auto-antibody. BUT, if the above scenario occurs, and the auto-antibody in the eluate is really strong (and in very rare cases), we will perform alloadsorptions on the eluate to adsorb out the auto-antibody, to see if there is an alloantibody present too. It's a lot of work, but twice now we have discovered just such an alloantibody causing a transfusion reaction. We would NOT expect one of our Hospital Blood Banks to do all this work! :):)

I'll hold my peace for now!

I agree entirely Eoin. In any case, it could be that an extra, so far unidentified antibody has caused the problem. Not all techniques and technologies detect all antibodies.

You're going to love this - NOT! 30 years minimum in the UK! :(:(

Steve, I will not spoil your thread by making any comments s to how we do resolve the problems, but I would, nevertheless, like to thank you for your kind words, which I will pass on to my team. Malcolm :D:D

Absolutely.

Oh I don't know; my Consultant isn't that scary really!!!!!!!!!!!!!!!!!!!!!!! :giggle::giggle:

I will check this with my Consultant on Monday, but I have a feeling there was a recent case involving a red cell pack in the UK that was both leukodepleted and was suspended in SAG-M (our version of Adsol). Don't fret about this over the weekend, in case I am wrong (again!).

Thanks Marilyn. Without doubt, the Adsol helps, but that notwithstanding, there are still cases in the literature.

Well, the thing that would concern me is that, if you are giving random group O units, some of them may well have high titre anti-A (and/or anti- in the plasma (even the plasma reduced units). This anti-A is most certainly clinically significant, depending upon the stature of the patient receiving the blood, their secretor status and the amount of blood they are receiving. There are many papers in the literature citing quite major transfusion reactions due to passive transfusion of high titre ABO antibodies (admittedly, mostly in patients of small stature and mostly involving plasma components, but some involving red cell components). I would be much more concerned about this, than the transfusion of A1 blood to an individual with an anti-A1, even if, as yet you have seen no overt transfusion reactions. It may be that the autologous red cells are not surviving for the usual 120 +/- 10 days, and that transfusions are having to be given more frequently than would otherwise be expected. Does your blood supplier not label those units that have been found to be high titre ABO antibody negative; because if not, they should.

Thanks for that. The only thing I would ask is, are the group O units tested for high titre ABO antibodies, or are they random from stock?

I have never seen one myself, but Geoff Daniels cites two papers in his book Human Blood Groups 2nd edition, Blackwell Science 2002, which are as follows: Coombs HI, Ikin EW, Mourant AE, Plaut G. Agglutinin anti-S in human serum. Brit Med J 1951; i: 109-111. and Constantoulis NC, Paidoussis M, Dunsford I. A natuirally occuring anti-S agglutinin. Vox Sang (old series) 1955; 5: 143-144. Good luck to you if you try to hunt down these papers! These two papers are also quoted by Peter Issitt and Dave Anstee in Applied Blood Group Serology, 4th edition, Montgomery Scientific Publications 1998. Good luck if you decide to hunt these papers down! From this, therefore, I would say that, yes, "naturally occuring" anti-S does exist, but that it is exceptionally rare (or, alternatively, it is not so rare, but that people have just not written up cases). :)

No, it's ANOTHER area where "teamwork" would have helped! Yours, Cynical of Croydon. :angered:

Welcome SDB.

Knowing what I do, I cn fully understand that.