We have performed two T&S s on a 79 year-old male who is in for a GI bleed.  He is on record as a A pos with no previous difficulties in testing.  But for both times we have done and ABO/Rh, his reverse A1 cells are giving a 2 or 3+ reaction (in tube).  Not due to rouleaux.  We have to run a 60 minute, 37C settle test in order to get a negative reaction. He is positive with anti-A1 lectin.

His CBCs have to be warmed in order to get a good RBC.   Cold agglutinin?  But the gel screen comes out negative - no interference.  That seems curious for what is almost certainly a cold agglutinin.

Just wondered what is going on here.  IgM antibody to a miscellaneous antigen?

Scott

It does sound like a cold auto, but I cannot explain the gel screen.

I agree - sounds like a cold auto, probably IgM. The IgG-gel cards are not exactly good at detecting IgM antibodies, Perhaps that's the reason for the nonreactive screens ?

What do O cells do in your standard version of the "reverse"?

7 minutes ago, exlimey said:

I agree - sounds like a cold auto, probably IgM. The IgG-gel cards are not exactly good at detecting IgM antibodies, Perhaps that's the reason for the nonreactive screens ?

What do O cells do in your standard version of the "reverse"?

Reverse O cells are negative with this patient's plasma.  I should also note that the (tube) poly DAT was about a 1 or 2+, with a negative anti-IgG.  We don't do anti-compliment testing.

Scott

2 hours ago, SMILLER said:

Reverse O cells are negative with this patient's plasma.  I should also note that the (tube) poly DAT was about a 1 or 2+, with a negative anti-IgG.  We don't do anti-compliment testing.

Scott

So the A1 cells are reactive, but the O cells are nonreactive. Interesting. I would have guessed autoanti-H, but that doesn't fit. Have you tested A2 cells ? Might be a weird compound antibody like anti-HI - needs the presence of both antigens to react well. Have you looked at something simpler, like anti-M, for instance ?

The DAT results suggest IgM/complement binding, but as you imply, further testing is required.

I frequently see cold auto's with negative gel....The gel is negative because incubated at 37 then spun.  We would then detect the cold in the back type and/or immediate spin crossmatches. 

Sometimes I do detect colds that carry over into the gel and they are nonsense reactions.  I tell all my staff, if you get crazy reactivity in gel try doing a short cold panel.

We do see cold anti-Ms (or colds that mimic anti-M) causing trouble with gel often enough -- they have to be resolved in tube, often with the pre-warming,  We are unlikely to do any further testing to identify what kind of cold antibody this is.  Its just unusual to get a patient with a strong cold agglutinin that does not interfere with our manual gel screen testing.  We are not complaining!

The patient has been transfused a few times with no problems.

Scott

Maybe there's a low on the A1 cell? Was there a lot change between the 2 times you tested the patient? Did you test the cell at any other phases? 

I think the idea that there is a odd antigen on the reverse A1 cells  that is reacting with patient IgM is probably the case here.  In fact, come to think of it, I believe we have come across this sort of thing has happened before.  (The previous ABO typing was actually done 6 months ago at another hospital).

Scott

We have had a couple cases like tkakin where the 'cold' shows in the tube but because the Gel is incubated at 37 it is spun to a negative screen. Not sure what a settle test is but what usually works for us is warming the patient's plasma well at 37C prior to testing with a1 cell and b cell. Sounds like a pesky cold agglutinin if warming corrects your MCHC. 

12 hours ago, SMILLER said:

I think the idea that there is a odd antigen on the reverse A1 cells  that is reacting with patient IgM is probably the case here.  In fact, come to think of it, I believe we have come across this sort of thing has happened before.  (The previous ABO typing was actually done 6 months ago at another hospital).

Scott

If by "odd antigen" you mean a low incidence/frequency antigen on that specific A1 cell/donor, it should be easy to resolve using another A1 cell (or set of Reverse Cells) - the forward and reverse would compliment each other. However, if everyone is having problems with this patient, it's unlikely to be the reverse cell(s).

Is the GI bleed due to ulcers ? H. pylori, perhaps. I think I read that some folks with H. pylori make cold autoantibodies.