Male patient case of ALL typed A pos in the past. Last night he typed as A pos but with 2+ anti-A.

Anti-A1 Lectin is reactive.

The Ab Id showd anti-K, but the AbSc is not typical for anti-K. AC and DAT neg.

Crossmatched Opos Kneg cells and it was incompatible.

Anti-K rarely reacts at room temp, right?

We are eluting the RBC reagent cells after the pos reaction to see what the Ab it is. These A cells are K neg. But what difference will it make? since the Ab screen was not helpful, would this be helpful?

Hope I was clear in my explanation.

Thanks

Hi Liz,

What reagent did yoiu use for your DAT? Was it monospecific anti-IgG, monospecific anti-C3 or polyspecific AHG? I'm just wondering if the incompatibility with the group O cells could be due to a cold-reacting auto-anti-HI.

Weakening of a patient's ABO groups is not unusual with acute leukaemia.

hello Malcolm,

The AHG was polyspecific.

The forward blood group is 4+.

Oh sorry, so he's got anti-A in his own plasma?

Well, his plasma is reacting with the A cells in the reverse grouping.

Point taken! Yes, that is what I meant, rather than it actually being anti-A.

In which case, I still wonder if there is another "cold reacting" antibody present (just for example, an anti-M) that may be reacting with the reverse grouping A cells and also with the group O cells in the cross-match?

So what shall I do now...

Well, what I've said so far is only supposition, but to take the "cold" antibody theory out of the equation, it may be worthwhile putting up a panel at 15-20oC (and 4oC). It may also be worthwhile including a group O cord cell, and also to put up about 4 other group A adult red cell samples.

great. thanks. I'll post what happens.

Point taken! Yes, that is what I meant, rather than it actually being anti-A.

In which case, I still wonder if there is another "cold reacting" antibody present (just for example, an anti-M) that may be reacting with the reverse grouping A cells and also with the group O cells in the cross-match?

Just a note, Malcolm, my first thought when reading Liz's post was anti-M. I always liked to rule out the horses before I started looking for unicorns. But then, in your line of work you get to see unicorns all the time! :eyepoppin

Just a note, Malcolm, my first thought when reading Liz's post was anti-M. I always liked to rule out the horses before I started looking for unicorns. But then, in your line of work you get to see unicorns all the time! :eyepoppin

True John, only too true!!!!!!!!

Yesterday, just as an example, we had a positive DL in a possible PCH and a patient with anti-C+S+U+K+Fyb - the latter was "fun" sorting out!!!!!!

I was going to vote for M too. It's the most common cause of unexpected positive results in a reverse type when you can't blame it on anti-A1. I have seen an auto anti-A1 but that would not react with the O cells. Reverse cells are usually pooled so they always contain M+ cells and most donors are M+ as well. Testing 2 or 3 M+ and 2 or 3 M- cells at RT often provides a quick ID. Once you know you have a cold, you can do something to avoid it interfering with your screen or ID.

Yes it was a cold allo. I could not identify it but did stop it from interfering. Merci.