performing ABORh on Stem Cell aliquot

[PammyDQ 21]

Prior to a HSCT transplant our blood bank receives 2 specimens for ABO Rh from the donor. One is peripheral, the other is an aliquot from the actual stem cell collection.

For many samples upon centrifugation of the stem cells, there is barely a cell button of rbcs remaining. We do MTS gel testing & only need 10ul of cells. When aspirating the rbcs at the bottom of the cell button, they become contaminated with stem cells, and any gel typing is junky looking and the control usually comes out positive. We often end up using an extremely dilute specimen and perform tube typing, disregarding the flocculation caused by the stem cells and make an educated decision by the most experienced techs of the blood type (which we have already presumed from the peripheral specimen).

Increasing our sample aliquot would deplete the volume of cells to be transplanted, so that is not an option.

Does anyone else have this problem or a better way of performing ABORh's on stem cell aliquots?

[Rh-fan 206]

We were dealing with the same problem, but now we receive (mostly) an EDTA tube, draw true the same needle.

When you have a sample with a lot of white cells in it we find that a tube test is most sensitive when you centrifugate, then dissolve (maybe wait 5 minutes) and than centrifugate again, then read the agglutination. But also as you stated only performed by very experienced technicians.

Good luck,

Peter

[PammyDQ 21]

Peter, please explain what you mean by "dissolve (maybe wait 5 minutes)".

Thanks!

[Rh-fan 206]

Peter, please explain what you mean by "dissolve (maybe wait 5 minutes)".

Thanks!

I mean "shake the tube gentle" just like you do when you would read the agglutination

[CM2 65]

I perform all my product typing in tube, forward and reverse. After you have done them a while your eye just gets used to filtering out the white clumps that sometimes form vs red cell agglutination. You have to stop expecting them to be 3+ or better like blood and instead accept tinier clumps. There is a fine granularity to rbc agglutination that doesnt shake away the same way the white cells do. You are not truly typing the patient, just trying to make sure products collected at the same time werent cross labeled in some way. If I had a real question about what ABO/Rh the donor really was, I would go to the peripheral blood sample collected pre/post procedure and compare to historical typing done on the pre-collection screening. This way you could do Du, gel, A1 lectin, whatever you need to clarify confusing results. The HLA results often have subgroup information on them, at least from Sharing Network out here in NJ.

Edited April 13, 2012 by CM2