Auto anti-D?

[Yanxia]

I have a patient, she is 90 years old, suspicious of AIHA.

She has not been transfused or receive any immunoglobulin. The blood group is A pos,her DAT is pos with IgG. The serum screening is pos with IgG anti-D and elution is Pos with IgG anti-D.

I am wonder because the autoantibody have clear specificity, it will not react with D neg cells both in polygrene and IAT, and with D pos cells the free antibody give 2+ reactive in IAT gel.

I don't know if it is because the antibody is weak so it does not show mimiking phenomenon.

Does it deserve to trace for? Thanks !

[Malcolm Needs ☆]

I would think, very strongly, that this is probably a mimicking anti-LW. If you can get hold of some, and I know this is difficult for you to do, group O, D- cord cells, these should come up positive with the lady's serum if I am correct.

That having been said, it doesn't make any difference to her treatment. It is still quite safe to give her D+ blood, as the antibody is an auto.

[jill]

Anti-LW does not react with 0.2M DTT treated red blood cells

so you could treat some Rh Positive cells and test then with

the patient's plasma. If no reactivity is seen then it is most

likely and autoanti-LW. If reactivity is seen maybe you could

absorb the the patient's plasma with Rh Negative cells, even

though her plasma does not react with Rh Negative cells,

to see if the autoantidody can be absorbed to exhaustion.

This would indicate a mimicking specificity.

Try and find out the patient's primary diagnosis. There are

diseases states where autoanti-LW forms transiently due

to antigen suppression on the surface of the patient's red

blood cells.