Anti-"D" in eluate of Rh negative pregnant women

[chupert]

So just curious if anyone has any thoughts about this case...The patient is pregnant with no history of blood transfusions and types B neg with panagglutination in her antibody screen (all 3 cells 3+) by solid phase testing.  A solid phase panel also shows panagglutination with scores ranging from 3-4.  A PEG panel shows weak reactivity with some, but not all of the Rh positive cells and all Rh neg cells are negative.  The patient did receive Rhogam about 2 months ago.  All clinically significant aby's have been ruled out, so I'm thinking a Rhig-D and solid phase is just....well being solid phase, but the DAT is poly=W+ IgG=w+ C3=0.  The eluate fits the pattern for anti-D perfectly with 2+ reactions, all other clinically significant aby's are R/O.  Soooo, I'm thinking either anti-LW or mom is weak D positive.  I did the weak D (despite the weakly pos DAT) and it was clean as a whistle negative.  I figure if the cause was a feto-maternal bleed I would at the very least have picked up some mixed field in the D typing (baby isn't delivered yet so I don't know the Rh type) I tested the patient's plasma and eluate in PEG with O neg cord cells and the reactions were a less than impressive W+.  I guess I would expect stronger reactions if it was an anti-LW with both Rh pos adult cells and Rh neg cord.  I was thinking I might run the partial D kit...DTT treat....and so on and so forth.  Thanks for any input : )

[galvania]

Anti-D given 2 months ago and nothing since - if that was a standard dose, I wouldn't really expect it to be still coating her red cells,e ven if she was a partial D - which I would check out if you can - but don't forget that serologically most of the tests are done in IAT and if she's got a pos DAT the results won't be valid.  Can you do molecular biology testing?

And I would look seriously at this being a strong fetal bleed, with the anti-D being her own anti-D.

also, have you got any chance of testing in gel, or even tube?  To rule out non-sp with solid phase

[Auntie-D]

We had a patient just last week with a known anti-D showing no reaction at all in the antibody screen on this occasion - she was panelled with enzyme and showed 3+ reaction. I didn't even know this could happen! I though anti-D and anti-K stayed detectable for life...

 

Could it be that she was like this lady and the new pregancy has elicited an immune response bringing titres to a detectable level again?