Hey everyone,

 

I have a patient who has a history of anti-E who comes in almost weekly to be transfused. The patient came in last Thursday for their pretransfusion testing. All testing and panels came out as expected for anti-E and units were antigen typed negative for E. However, when performing the crossmatches, they came up 3+ positive at the 37 C phase and were negative at IS and AHG phases. We sent samples to our reference lab for identification and they reported that the patient has HLA hemagglutinins with a weakly positive DAT in all phases. They also performed an eluate that was non reactive against a panel of all reagent red cells. They want to transfuse RBCs to this patient so I am wondering if I should be worried about the positive crossmatches at 37 C or is there anything else that can be done to find compatible blood for the patient. Thanks for any help you guys can give.

I 'm sorry but I find it really wierd that the Coombs phase is negative if your saline at 37 is positive.  Are you testing in gel or in tube?

If the pos reactions rally are due to anti-HLA antibodies I would not worry about red cell transfusion.  You might have problems with reduced life span for platelets though

The only thing I would add is that, if you really are convinced that the antibodies are HLA, and you are worried about the cross-match being positive, you could treat the red cells you are using in the cross-match with chloroquin, which will remove any HLA antigens that have been adsorbed onto the red cell surface.

The crossmatches were done in tube using LISS reagent. And I agree about it being werid that it is only reactive at 37 why I brought this up here to see about anyone else's thoughts about this.

 

The reference lab did remove the reactivity present by using chloroquin treated red cells. I am just being cautious since I have not seen reactivity like this, or as strong as the reaction is at 37 with HLAs.  Thanks for your guys input about this

Are certain the reactions at 37 were agglutination. A lot of times rouleaux is very evident a that phase.

We did not check for rouleaux and did not think about that due to the strength of the reaction at 37 C. Next time we get a specimen for the patient I will check for rouleaux and see if its present or not. Thanks

We did not check for rouleaux and did not think about that due to the strength of the reaction at 37 C. Next time we get a specimen for the patient I will check for rouleaux and see if its present or not. Thanks

 

Check the haem results to see if they have had an ESR done - if the ESR is normal you can rule out rouleaux. There may even (stab in the dark) be a film result identifying rouleaux.

 

ETA - ignore my comments. If the patient is in weekly anyway it's probably not necessary.

Edited September 14, 20159 yr by Auntie-D

I remember reading an interesting section in Geoff Daniels' Human blood groups 3rd ed. about HLA antibodies. pg 513 "Antibodies to HLA antigens on red cells have generally been considered clinically benign, but there is now substantial evidence that such antibodies have been responsible for both immediate and delayed HTRs."

Just an update on this. The patient came back in yesterday for pre transfusion testing and the cause of the reactions at the 37 C phase was being caused by rouleaux. Thanks again everyone for the feedback about this.