At our facility we are having a discussion about transfusing WAA patients.

When the WAA is expressing we give phenotypically (for Rh and Kell) matched packed cells. When the antibody screen is negative is it necessary to continue with phenotypically matched packed cells?

I only try to give Rh phenotype specific. My experience is if I don't the pt will have Rh abs to those ags they lack in the near future.

At our facility we are having a discussion about transfusing WAA patients.

When the WAA is expressing we give phenotypically (for Rh and Kell) matched packed cells. When the antibody screen is negative is it necessary to continue with phenotypically matched packed cells?

I agree with you on this one Sherry, rather than David, in that I would also have K matched blood, as the K antigen is highly immunogenic.

Personally, I would also carry on with giving Rh and K matched red cells, even when the auto-antibody appears to have disappeared and the DAT is negative. Petz and Garratty state that autoantibodies have a nasty habit of re-appearing.

I have never considered K typing these pts - I shall discuss it with my Medical Director. Thanks.

Malcolm,

We recently had a patient that had a previous WAA that returned 5 years later. Antibody screen is negative. Would you still give phenotipically matched packed cells?

If we have a patient with no history at our facility and a negative screen, how do we know that they didn't have a previous WAA ?? If we get a negative screen, we say hooray and move on.

This topic has caused some debate at our facility. Thank you for your input!

Malcolm,

We recently had a patient that had a previous WAA that returned 5 years later. Antibody screen is negative. Would you still give phenotipically matched packed cells?

If we have a patient with no history at our facility and a negative screen, how do we know that they didn't have a previous WAA ?? If we get a negative screen, we say hooray and move on.

This topic has caused some debate at our facility. Thank you for your input!

Yes, I can see from where you are coming Sherry, but the problem is that you do know in this case, and, morally, even if not scientifically (although I would go with Petz and Garratty) I think you have to honour it. If you didn't know (but another institution elsewhere did), than that is fair enough; I wouldn't blame you in the least for giving random blood under such circumstances.

If waa is not showing, there is no any benefit to give any special treatment. Instead, do electronic crossmatch. The reason is simple: No allo antibody seen because your gel or peg screen is negative.

Give phenotype similar red cells only if you do not have time to do adsorptions to complete antibody workup and pt is in life threatening situation. This is a method should be reserved as the last resort if your reference lab cannot complete in time. Also, you most likely are not lucky enough to have these phenotype similar red cells even from a big blood center. Coordination with the nurse station is a key to prevent the last minute rush.

yes, i can see from where you are coming sherry, but the problem is that you do know in this case, and, morally, even if not scientifically (although i would go with petz and garratty) i think you have to honour it. If you didn't know (but another institution elsewhere did), than that is fair enough; i wouldn't blame you in the least for giving random blood under such circumstances.

What I meant was that, if you know a patient has had such a condition in the past, which may return, it is best to give them Rh and K cross-matched blood (even if you are giving this by electronic issue) so that you don't build up problems for the future, when they come in with Rh and/or K antibodies.

We send waa workups to our reference lab. They do not give us rh or K matched units but units compatible with absorbed serum. I think wasting special screened units when there is no allo antibody is not the best way to care for the patient.

Believe me Barbarakym, wait until a WAA patient who is R2R2, K- has made anti-C+e+K, plus any other antibody (say, for example, anti-Fya) and,as a Reference Laboratory Manager, whose Laboratory has to do the work-up and the cross-match, and you will realise that it is NOT a waste of special screened units (I would also suggest that you read Petz and Garratty on the subject).

Malcolm is right.

Up to 50% of the patients with WAA make allo antibodies against Rh and K. When they make allo antibodies the immune system is triggerd and the WAA can become stronger or even make a switch for IgG1 tot IgG3 subclass (meaning more red cel destruction). So selecting Rh and K compatible units is no waste.

Believe me Barbarakym, wait until a WAA patient who is R2R2, K- has made anti-C+e+K, plus any other antibody (say, for example, anti-Fya) and,as a Reference Laboratory Manager, whose Laboratory has to do the work-up and the cross-match, and you will realise that it is NOT a waste of special screened units (I would also suggest that you read Petz and Garratty on the subject).

Can you kindly tell me the date and/or title of the article by Petz and Garratty Malcolm, Thank you.

Can you kindly tell me the date and/or title of the article by Petz and Garratty Malcolm, Thank you.

Hi Liz,

It is in Petz LD, Garratty G. Immune Hemolytic Anemias. 2004 (2nd ed). Churchill Livingstone; one of my favourite books. Specifically, it is Chapter 10, Blood Transfusion in Autoimmune Hemolytic Anemia, and, even more specifically, they discuss this on pages 388 and 389.

Table 10.10 on page 388 is quite revealing (particularly with regard to the top 3 alloantibody specificities in WAIHA).

Edited October 13, 201113 yr by Malcolm Needs
Needed to add a bit.

Cher Malcolm, Merci!

My pleasure.