A pregnant women forward typing A antigens 4+,B antigens4+,auto control neg; reverse typing A cells 1+ stronger, B cells 1+ stronger, O cells is neg.

Antibodies screening is neg.

 Any suggestion is appreciated.

Edited June 13, 201411 yr by shily

This one stretches the brain a bit Yanxia!!!!!!!!!!!!!!

 

One possibility (although it is a bit "left field") is that the pregnant lady is a cisAB, as they can have low levels of anti-A and anti-B (usually only anti- in their plasma.

 

Another possibility is that there is overlapping specificities of A- and B-transferases (GTA and GTB) and that the anti-A and anti-B are directed against the part of the A and B antigens that are "missing", but this is even less likely than a cisAB, and that, in itself, is unlikely.

Thanks, Malcolm.

I prefer the partial antigens one. I have seen a case of CisAB, the B antigens is weaker than normal , maybe 1+stronger, in this case ,both A and B antigens is as strong as normal AB group.

Malcolm , I just search on line, and find that some Cis AB reverse type looks like O , but there is no description of forward type strength , what a pity.

Have you r/o cold agglutinin? 

If it were a cold agglutinin, I would have thought that it would have agglutinated either the group O reverse cells or the screening cells somewhere along the line.

Was the screen cooked at rm temp, 37, and AHG?

Could you have an allo-antibody that is on the A and B reverse cell and not on the O cell and only detectable at Rm temp?

Alana

Did you look at "agglutination" under the microscope?  Since its weak, it sounds like possible Rouleaux to me

Thank you all .

I do the screen at room temp in tube and gel and gel AHG, and they are all neg.

I have not look in at aggutination under microscope, think about the reaction is 1+stronger, and non reaction is macro neg.

 

Your suggestions about the testing  are very helpful to me, if you can think about something more please tell me.

I was thinking of anti-M, especially if the O cell is not a pooled cell whereas the reverse A & B cells are, but your room temperature screen would have shown the anti-M. Rouleaux also should have showed up with the O cell.  Was the reverse type in gel?  Maybe a reaction with the gel diluent in the reverse?

Has this patient received any transfusions including IVIG?

Have you tested A2 cells with the patients plasma?

Has this patient received dose(s) of RhIG or Rhophylac? How long ago?

Edited June 15, 201411 yr by GOSBB

I saw something like this in the past and it really threw me for a loop.

 

Did you try washing your ABO-grouping cells with saline, resuspending and then testing the patient's plasma?

 

Some patients can have antibodies against the preservatives in the ABO grouping reagents. I don't know what O cells you used in your blood type discrepancy workup (if they were screening cells, or donor cells) but it might still be worth a shot because the preservatives could be different.

You did absorption-elution using serum and red cell A, B and O? You can help confirm the antibody reverse ...

The reverse O cells is pooled cells at the samepreservation with A1 and B reverse cells, they are the same lot . I do the reverse typing in gel and in tube, and they show the same pattern.

This patient has never receive any IVIG or blood transfusion.

I have not use A2 cells with the plasma, I think I need to do it.

this patient nver received dose(s) of RhIG or Rhophylac.

I would do a cold panel - I also think that the most likely is an antibody against an atigen nothing to do with ABO, present on the A and B cells but not on the O cell.  If you are using the cells I think you are using, then the A and B cells are pools of different donors, and the O cell is a single donor - so it might well be an anti-Lewis, or M or N or P1 or.......

 

 

I would do a cold panel - I also think that the most likely is an antibody against an atigen nothing to do with ABO, present on the A and B cells but not on the O cell.  If you are using the cells I think you are using, then the A and B cells are pools of different donors, and the O cell is a single donor - so it might well be an anti-Lewis, or M or N or P1 or.......

 

 

Thank you Anna. The O cell is pools of 3 donors.