Mixed Field on Cord Blood Blood Types

[MId West Banker]

Is any one else getting mixed field codes from the Vision when performing blood types using cord blood samples? This does not happen all the time but enough for us to take notice. We wash the sample 4-6 times and rerun the sample and get the same results. contaminated with Mom's blood??? Old baby cells??

[Malcolm Needs ☆]

16 minutes ago, MId West Banker said:

Is any one else getting mixed field codes from the Vision when performing blood types using cord blood samples? This does not happen all the time but enough for us to take notice. We wash the sample 4-6 times and rerun the sample and get the same results. contaminated with Mom's blood??? Old baby cells??

Is this ABO typing, or other typing?

[MId West Banker]

ABO and Rh typing

[Malcolm Needs ☆]

47 minutes ago, MId West Banker said:

ABO and Rh typing

Hmmmmmmmmmm, that makes life more difficult!  If the mixed-field reactions were only seen in the ABO typing, that would be fairly easy to explain.  As they are in the Rh type as well, the explanation may be much more difficult, not least because Rh antigens are proteins, and so are fully expressed at birth.

I just wonder if, in the cases you see, there is a noticeable difference between the D type of the mother and the baby.  For example, is the mother D Positive and the baby mostly D Negative, with just a few D Positive red cells in evidence?  This could be explained by there having been a foeto-maternal haemorrhage, largely from the maternal circulation to the foetal circulation.  Obviously, If the mother is D Negative and the baby types mostly as D Positive, with just a few D Negative red cells in evidence, the same applies.

Am I going completely down the wrong street?????????????

[Bet'naSBB]

we see it quite a bit.  we usually take it to the bench and wash a suspension and re-run it the "old fashioned way" in tube.......if still MF then we do not report unless they get us a heel stick for repeat testing bc it could mean maternal contamination.....if no MF - then report the manual testing.