You have a gel screen/panel that shows a clear pattern for M showing dosage. You run it in 30 minute inc saline tube, all negative. The patient has no history of transfusion -- so apparently this is a naturally occuring anti-M, or possible a cold showing M reactivity.

What next if one wants to crossmatch a couple of units?

Thanks, Scott

In the UK, we would give cross-match compatible blood (not typed to be M-) if the anti-M does not react strictly at 37oC, in line with Daniels G, Poole J, de Silva M, Callaghan T, MacLennan, S, Smith N. The clinical significance of blood group antibodies. Transfusion Medicine 2002; 12: 287-295.

In the UK, we would give cross-match compatible blood (not typed to be M-) if the anti-M does not react strictly at 37oC, in line with Daniels G, Poole J, de Silva M, Callaghan T, MacLennan, S, Smith N. The clinical significance of blood group antibodies. Transfusion Medicine 2002; 12: 287-295.

I agree with Malcolm

Issue gel AHG compatible units. Things can get sticky though if the anti M reacts when doing the immediate spin crossmatch.

Prewarm technique in tubes, crossmatch compatible at AHG. If serum reacts at AHG using this technique, we would then have to find M-negative units.

AT our place...we see this a lot with our population (we do not run saline tube method), give gel crossmatch compatible blood.

For pregnant patient we run tube screen (with LISS) and if reacting at 37/AHG, we do prewarm screen. If the prewarm screen comes out positive, our MD gives us guidance. Most cases MD wants to give gel crossmatch compatible. But if prewarm is reacting, we get heads up on what give it to baby.[

QUOTE=SMILLER;49365]You have a gel screen/panel that shows a clear pattern for M showing dosage. You run it in 30 minute inc saline tube, all negative. The patient has no history of transfusion -- so apparently this is a naturally occuring anti-M, or possible a cold showing M reactivity.

What next if one wants to crossmatch a couple of units?

Thanks, Scott

In the UK, we would give cross-match compatible blood (not typed to be M-) if the anti-M does not react strictly at 37oC, in line with Daniels G, Poole J, de Silva M, Callaghan T, MacLennan, S, Smith N. The clinical significance of blood group antibodies. Transfusion Medicine 2002; 12: 287-295.

In the Netherlands we select M neg typed units when the anti M is reactive at 37oC (not strictly reactive but also reactive). So whenever the anti M is reactive (also) at 37oC we select M neg units. Based on the same publication (different interpretation).

Peter

In the Netherlands we select M neg typed units when the anti M is reactive at 37oC (not strictly reactive but also reactive). So whenever the anti M is reactive (also) at 37oC we select M neg units. Based on the same publication (different interpretation).

Peter

Under these circumstances, we will issue "historically" M Negative units, if the hospitals so wish, but rarely currently tested M Negative blood (because we want to reserve our currently phenotyped blood for known clinically significant antibodies, such as anti-Fya, anti-Jka, etc).

Our units are mostly 'historical' phenotyped. All donations are tested for ABO CcDEe and K (every donation). A selection of those that are D, c or e neg are then further tested for Fy, Jk, MNS (and some others). When a donation is typed neg on 2 donations, the typing is then printed on the label (every donation after that). So we don not retyp our donatiosn if they are typed twice.

Peter

Yes, we are moving towards that too Peter, but, at present, we are still stuck with typing each time.

Scott, just curious to know the strength of the reactons.

You have a gel screen/panel that shows a clear pattern for M showing dosage. You run it in 30 minute inc saline tube, all negative. The patient has no history of transfusion -- so apparently this is a naturally occuring anti-M, or possible a cold showing M reactivity.

What next if one wants to crossmatch a couple of units?

Thanks, Scott

RR

Very weak but match M -- even showing dosage like an M. Which happens with some nusiance colds.

Scott