new specimen following transfusion reaction?

[Liz0316]

Is it just me or do others feel that following a transfusion reaction, a new specimen should be collected and tested if addtional units are needed? My techs feel that if the work up is negative, any allocated units can still be given. I can't find a regulation about this. Any thoughts?

Liz

[R1R2]

I agree with your techs. Do a transfusion reaction investigation and if negative continue to issue any previously allocated units.

[Malcolm Needs ☆]

I also agree with your techs, assuming the units allocated were re-cross-matched by IAT, including the index unit, to ensure that there were no alloantibodies detected against low incidence antigens.

[Changezi]

Same here agreed with malcolm Needs and above

[R1R2]

I also agree with your techs, assuming the units allocated were re-cross-matched by IAT, including the index unit, to ensure that there were no alloantibodies detected against low incidence antigens.

Is a recrossmatch by IAT a requirement in the UK? It is not in the US. At our facility we would not do this if the transfusion reaction workup is negative.

[Dr. Pepper]

I agree with the above posters as well. We do not redraw/retest if the workup is negative.

[Deny Morlino]

No redraw / retest here either as long as it was within the antibody screen window.

[Malcolm Needs ☆]

Is a recrossmatch by IAT a requirement in the UK? It is not in the US. At our facility we would not do this if the transfusion reaction workup is negative.

We do so, just in case there is an antibody directed against a low incidence antigen, such as anti-Wra, lurking in the plasma, and one of the units happens to be Wr(a+). Our screening cells and panel cells are deliberately Wr(a-), as anti-Wra is a fairly common antibody.

[Abdulhameed Al-Attas]

Ditto.

[Dr. Pepper]

We do so, just in case there is an antibody directed against a low incidence antigen, such as anti-Wra, lurking in the plasma, and one of the units happens to be Wr(a+). Our screening cells and panel cells are deliberately Wr(a-), as anti-Wra is a fairly common antibody.

In the US we are required to do a DAT on the reaction workup. Assuming there were still some surviving donor cells in the post-rxn sample, if the patient did have the undetected anti-Wra, we would see a mixed-field positive DAT. The next step would be to do a full crossmatch with cells from the offending unit, see the incompatibility, try to ID the antibody and (full) recrossmatch the remaining units. But how often does this scenario happen as compared to non-RBC antibody reactions or coincidental symptoms? Do you feel that a negative DAT does not offer enough protection, even though the odds of chancing upon another Wr(a+) unit are so slight?

[John C. Staley]

You can add my vote to the majority above. If your routine workup is negative, unless there is a good reason to do more (and I can not think of what that might be) I would carry on with the original sample.

[Malcolm Needs ☆]

In the US we are required to do a DAT on the reaction workup. Assuming there were still some surviving donor cells in the post-rxn sample, if the patient did have the undetected anti-Wra, we would see a mixed-field positive DAT. The next step would be to do a full crossmatch with cells from the offending unit, see the incompatibility, try to ID the antibody and (full) recrossmatch the remaining units. But how often does this scenario happen as compared to non-RBC antibody reactions or coincidental symptoms? Do you feel that a negative DAT does not offer enough protection, even though the odds of chancing upon another Wr(a+) unit are so slight?

To be perfectly honest Phil, I agree entirely with your sentiments. I think that, since I started work in 1973, and as far as I can remember, I have only ever seen one clinically significant haemolytic transfusion reaction, as opposed to a clinically insignificant serological transfusion reaction, with a negative DAT. That having been said, that is what we do, because that is what is written in the procedure (which I did not write)!

Personally speaking, I think that what you are saying is both logical and safe, but hey, who am I to argue with the people that write these policies!

:cries::cries:

Edited December 4, 2012 by Malcolm Needs
Replied to the wrong member!!!!

[BBCLS]

I agree with the above posters as well. We do not redraw/retest if the workup is negative.

Same here.

[Liz0316]

thank you everyone for your in-put! Interestingly I did see one majorly famous hospital's SOP did say a new specimen is required, but I'll give in to the majority.

Have a great day

Liz

[EDibble]

Same here regarding the DAT, but we also perform one on the pretransfusion sample, as well as repeat Type, Rh, and IAT on post specimen.

[Eagle Eye]

This is what we do. As part of transfusion reaction process, we re crossmatch implicated unit+ all allocated units using IAT. If all units are compatible and workup was negative....we continue to use pre specimen.

I also agree with your techs, assuming the units allocated were re-cross-matched by IAT, including the index unit, to ensure that there were no alloantibodies detected against low incidence antigens.

[Mabel Adams]

I'm with Dr. Pepper. Seems like if we are going to do AHG xms after a reaction to find antibodies incompatible with a low freq Ag that we should do them all of the time. It isn't as if a reaction workup is done only when there is a definite immunologic cause so we have a higher degree of suspicion than usual that a unit might be incompatible. Also, as mentioned above, if there were an anti-Wra then you have closed the barn door after the cows escaped since the odds of having two Wra pos units in a batch is pretty small. I would want to see scientific evidence to justify the policy. Sometimes procedures get written because they make one of our more compulsive brethren feel better (note I said more compulsive--not trying to imply that we aren't all compulsive).

[Malcolm Needs ☆]

I would want to see scientific evidence to justify the policy.

It is in the 2012 BCSH Guidelines for pre-transfusion compatibility procedures in blood transfusion laboratories, Key Recommendation on page 26. "An IAT crossmatch must be used if the patient's plasma contains, or has been kown to contain, red cell alloantibodies of likely clinical significance."

Clinical Significance of alloanti-Wra. Transfusion reaction: None to severe/immediate or delayed/hemolytic. Reid ME, Lomas-Francis C, Olsson ML. The Blood Group Antigen FactsBook 3rd edition 2012 Elsevier, page 392.

I agree wholeheartedly that you would be hugely unlucky to find two units in your stock that both express the Wr(a) antigen; hugely unlucky, but NOT impossible.

The other thing is Mabel, that once a person has made an alloantibody directed against a low incidence antigen, they very often make a "soup" of alloantibodies directed against a number of low incidence antigens (or, at the very least, alloantibodies that cross-react with a number of low incidence antigens), and so once such an antibody has been identified in the palsma of a patient, we would always perform a serological (IAT) cross-match.