gagpinks

Couldn't agree more John - excellent point!

No Mabel, as Heather says, polyclonal anti-D is a whole soup of anti-D specificifities that will be able to bind to all the thirty or so different epitopes that are expressed when the normal D antigen is present.
When a partial D is present, some of those epitopes will be missing (not expressed) on the red cell, and the anti-D specificities that are directed against those missing epitopes will remain free - and, thus, will be able to bind onto the foetal red cells, if they express a normal D antigen.
If you like, think of it as alphabet soup.  You eat all the bits of alphabet from A to, oh, I don't know, let's say T, as you are a red cell expressing a Partial D antigen, but you do not eat (express) epitopes U to Z.  Along come some red cells from your baby, and your baby is a red cell expressing ALL of the normal D epitopes, Your baby will then be able to eat (be sensitised by) the letters U to Z in the soup (assuming it is on solids, of course)!!!!!!!!!!!  The immune system will be able to recognise a red cell that has eaten letters U to Z and will destroy these red cells IN the RES.

If we are to transfuse MB treated products for anyone born after 1996, why doesn't my local blood service supply MB treated cryoprecipitate?

Malcolm - this is why I love this site! True sharing of knowledge

Like Mabel, I would find it difficult to see why a normal healthy baby would suddenly require a transfusion a week after being born.
 
Of course, shiley is also correct in saying that the FIRST thing you should do is Rh type the baby, as a minimum for the C and c antigens, but, if the baby is NOT c positive, I can see no reason whatsoever why you would want to give c negative blood, when the baby's DAT was negative, and the mother's anti-c did not appear until after delivery, and the baby's own immune system is incapable of producing such an antibody itself at this stage of life.
I think you are worrying unduly.

The concentration of the maternal alloantibody is actually higher in the baby's circulation than in the mother's circulation, as the transfer of the antibody across the placenta is active, rather than passive (see Mollison), and so, if the DAT is positive, but there is no detectable antibody in the maternal circulation at birth, then it may be worthwhile identifying the specificity from an eluate from the baby's red cells - the positive DAT may just be ABO antibody, after all.  If there is no specificity, other than ABO, then I would quite happily give c+ blood to the baby, rather than hang about waiting for c- blood, when there is absolutely no reason so to do, other then a "vague worry".  Even if the baby was a female, and c-, I still wouldn't worry about giving c+ blood because, as I said above, the baby is unable to make anti-c at this stage.

I think you-all missed the point of gagpinks' posting.  It was an hypothetical question, "Would you provide little-c negative rbcs or rbcs untested for little-c to this infant if transfusion was required on day 7?"

Anyone doing this who uses UBS?