FMH

[gagpinks]

Hi 

We had patient who is O Rh D positive and baby is A Rh D positive.  Baby born very anamic therefore clinician wanted us to perform Kle to see any large FMH . A lady had positive Kleihuer and estimate 50 To 60 ml bleed. And baby had 2 unit top up transfusions. Just wondering wouldn't mother will have any transfusions reaction due to this much amount of incompatible blood. 

[Malcolm Needs ☆]

The chances are that this bleed is a chronic, rather than an acute bleed, and, I suspect that there is a certain amount of "accommodation" going on, rather like there is in the case of an ABO solid-organ mis-match.  At the same time, however, it must be remembered that the A antigen on the red cells of a foetus is very much weaker than the A antigen of an adult (the number of antigen sites per red cell are much lower than the number of antigen sites per adult red cell) as a result of the "A transferase" being very inefficient during foetal life, and with these two factors "coming together", as it were, I am not that surprised.  I am more surprised, if anything, that you can still detect such a large volume of group A red cells.

[gagpinks]

Thanks Malcolm !!