Question:

How do you report the Rh type on a cord blood with a positive DAT?  If the Rh is negative with a positive DAT do you take it through DU and report the Rh type from there?

As Rh grouping reagents are, these days, almost, if not absolutely, monoclonal IgM antibodies, and therefore, not affected by a positive DAT, one wonders under what situation this would pertain, unless the mother was D Negative and the antibody causing the baby's DAT was positive.  If this were so, why would you not be able to use the results of the IgM monoclonal reagents?  If, for some reason you could not (the reason why escapes me), you could treat the red cells with chloroquine (although this , in itself, weakens the Rh antigen expression), or, of course, you could give anti-D immunoglobulin anyway, and assume that the baby is D Positive, with no evidence whatsoever, and expose the mother to 1) a human-derived antibody, which may be carrying a virus that has yet to be recognised, that they almost certainly do not require, and 2) a human-derived antibody that may cause a severe reaction due to, for example, anti-IgA,

I really WOULD advise that you rely on the results you get with IgM grouping reagents, and stop worrying about the tiny chances that there would be clinical sequelae, and I (seriously) would advise the likes of the FDA do the same!

Our SOP requires that newborns, who test negative with anti-D by immediate-spin test, must be tested for Weak D using anti-D antiserum formulated for Weak D testing.  If the Weak D Control is agglutinated, we report Rh type of the newborn as "Indeterminate" and "RhIG indicated" for the mother if the mother is Rh negative.

   We test the father of the baby. If he is Rh- Positive , we automatically give the mother RhoGam.

lucky you if you know who the father of the baby is!!!!!  Minefield!!

On ‎6‎/‎17‎/‎2018 at 1:17 AM, Dansket said:

Our SOP requires that newborns, who test negative with anti-D by immediate-spin test, must be tested for Weak D using anti-D antiserum formulated for Weak D testing.  If the Weak D Control is agglutinated, we report Rh type of the newborn as "Indeterminate" and "RhIG indicated" for the mother if the mother is Rh negative.

Same here!

On ‎6‎/‎17‎/‎2018 at 6:58 AM, Kathyang said:

   We test the father of the baby. If he is Rh- Positive , we automatically give the mother RhoGam.

We do the same. We also offer to do a blood type at no charge if the parent(s) want to bring the baby in to the lab in 6 months or so in order to get an accurate blood type.

We can't justify keeping the monoclonal anti-D that picks up  category VI partial D at IS for using it twice per year.  We don't want to pick those up on the mom because we want to call category VI Rh negative.  We don't test donors so don't need the reagent for that.  We wouldn't want anyone to mistakenly use it as a normal anti-D.  We usually turn them out as unknown and give RhIG.  Sometimes the weak D test does a little heat elution on a weak positive DAT and the control and test are both negative at AHG so you can call it negative.  We also have a procedure for doing a heat elution on these so we can then test the cells through AHG.