Anti-A1--Significant?

[CCard]

I would like to hear from the blood banking community regarding Anti-A1 when detected and what transfusion practices are observed; my personal experience is while it is present, transfuse with group O (or A2) red cells, and resume the use of group A when the antibody is no longer detectable.

[Cliff]

Chris, that is our practice too.

What blood type do you assign to these patients? We are currently calling them A2 in the computer.

[Dawn]

We have had a few cases of hemolysis caused by passively acquired anti-A1 from platelet products. To resolve this we started screening our group O platelet products for high titers of anti-A1 and anti-B. If either titer is high we restrict the unit to a group O patient.

[Kevin]

We see more >A1 passively infused through IV Ig infusion. This has caused some hemolysis issues in the past. I do not believe there is a >A/>B titer limit placed on pharmaceutical manufacturers to prevent this.

[blut]

Hi, all,

Maybe I've misunderstood what others have written, but anti-A1 (the type made by A2 patients) is usually (but not always) a cold-reactive clinically insignificant antibody. If anti-A1 in an A2 or A2B patient does not react at 37C, crossmatch compatible blood can be issued. There is no need to give group O or A2 RBC in these cases. Anti-A1 is the same as most examples of anti-N, -P1, -Lea, etc. If non-reactive at 37C, crossmatch-compatible RBC can be issued and antigen-negative units are not required.

Cases of hemolysis caused by anti-A1 produced by A2/A2B patients exist but are rare. Anti-A made by Group O and group B people (has a part that reacts with both A1 and A2 rbc) is another matter.

Cheers, Pat

TraQ: http://www.traqprogram.ca

[Kevin]

How have your A subgroup patients tolerated transfusion of random A units? We do not see many >A1's but I honor every one I see and give A1 neg units without investigating if the antibody is IgG or not.

[Dawn]

If the patient currently tests positive with A1 cells then we usually give group O red cells. If we are really short on group O red cells then we screen our group A units to find the A2's and transfuse those.

[calynn]

We will give random A units to patients with Anti-A1, but we crossmatch them first-- through the IgG phase. If the crossmatch is compatible, we give the unit. If not we

will give O. We've had no problems doing this, and I can only think of one patient who

was incompatible with random A units. He did fine with O's.

[ChrisH]

If the patient is demostrating their anti-A1 then we will give them A1 neg or O units. I know it is not clinically significate, but we need to give Immediate Spin negative units. We would do the same for N, P1 or any other cold antibody. If they are reacting at IS then the crossmatch is incompatable.

[John C. Staley]

Have you considered, for such patients, skipping the IS and doing the AHG xm?