What is in the reagent should be used to confirm Donor and Newborn initial D negative result?

We always use an anti-D that is known to detect Partial D VI.

I have 2 offers from DiaMed (BioRad) and do not know which one to use. Which one do you advise to confirm Donor and Newborn initial D negative result?

Merci

Liz,

We do not test donors here except for the retypes required by AABB. For cord blood confirmation of Rh I use a product from ALBA Bioscience called Anti-D delta that is specifically designed to identify D VI. It is a tube method, but is an immediate spin method. For our lab the tech time saved pays for the reagent very quickly. It has a good outdate (the lot I received in mid-September outdates 4/15/2013). Not certain if you are set on column agglutination as the only method, but it is an option. Good luck!!

Ah, I just remebered I only need for donors as the newborn cards are DVI+ so they do detect the VI+.

Deny, Why don't you check the negative donors for weak D?

It is standard SOP in USA when retyping rbcs from the supplier - only have to do IS D typing on units labeled Rh(o)D Negative.

Oh yes Dave, I forgot that you have a supplier. We do not have a centralised BB. We do everything.

Do you ever have donors come to you and if they did I am sure you would confirm a D neg result. Same thing in Cord blood and newborns. Has BioRad started in the US?

Dear Liz

I would definitely recommend the first of the 2 for donors. It is a liquid monoclonal anti-D to be used in an IAT in conjunction with ID cards (not for tube) and is really very avid and will pick up almost everything!. The other product is a card with polyclonal (human) antisera that uses enzymes, so unless you are using Diluent 1 with something else already, I would say it is not such a good idea.

But you could also use a card that has 2 different anti-Ds on it, one of which will detect DVI. That way, you would not miss anything but the weakest of weak.

Having said that, Switzerland is to start genotyping ALL donors that react as D neg in the cards as of next year

Edited November 18, 201113 yr by galvania
added a phrase to make clearer

Griffols does an 8 well card that does 2 Ds and also Kell

Biorad is marketing in the US now.

Oh yes Dave, I forgot that you have a supplier. We do not have a centralised BB. We do everything.

Do you ever have donors come to you and if they did I am sure you would confirm a D neg result. Same thing in Cord blood and newborns. Has BioRad started in the US?

Hi Liz - we do Weak D on our donors that we draw and also on Rh= cord bloods. Those are the only instances for weakD testing, unless we want to satisfy our own curiosity.

Biorad is marketing in the US now.

But not with their gel system . . . soon.

David is correct. Marketing antisera prior to that date is giving them a foot in the door - I'll bet that was a deliberate decision just for that reason.

Dear Liz

I would definitely recommend the first of the 2 for donors. It is a liquid monoclonal anti-D to be used in an IAT in conjunction with ID cards (not for tube) and is really very avid and will pick up almost everything!. The other product is a card with polyclonal (human) antisera that uses enzymes, so unless you are using Diluent 1 with something else already, I would say it is not such a good idea.

But you could also use a card that has 2 different anti-Ds on it, one of which will detect DVI. That way, you would not miss anything but the weakest of weak.

Having said that, Switzerland is to start genotyping ALL donors that react as D neg in the cards as of next year

Hi Anna,

Thank you for the reply. I read the information much closer and you are perfectly right, the other product advises to use this one to confirm negative donors!! I have informed the supplier of what you suggested. However, why doesn't DiaMed (BioRad) manufacture a donor card with reverse grouping and DVI+ (positive for VI) ? It would make things faster just as the newborn card but with the reverse.

Thanks

Anna, the card that has 2 different anti-Ds on it, one of which will detect DVI, does not have reverse grouping, I want to make the work fast and easy.

Hello Anna, and others using Biorad and Diamed, I hope you can answer this. I found that DiaMed does have a card for donors: Forward with the DVI+ and reverse. It would be very practical to use (all in one) BUT the insert says that I still must use the liquid monoclonal anti-D on those donors that have a neg D result. Why is that so? Isn't it the same composition? Obviously not, what does the liquid have that the card does not?

Thank you.

Hello Anna, and others using Biorad and Diamed, I hope you can answer this. I found that DiaMed does have a card for donors: Forward with the DVI+ and reverse. It would be very practical to use (all in one) BUT the insert says that I still must use the liquid monoclonal anti-D on those donors that have a neg D result. Why is that so? Isn't it the same composition? Obviously not, what does the liquid have that the card does not?

Thank you.

You can use what Diamed/Biorad call 'D blend' to cover all (most) D-types.

But separate to this there should always be two groups done on a patient from seperate alequots for ABO and D. ABO is covered - you can either use whole blood (forward), spin (reverse) or packed cells (forward) spin (reverse). You also need two Ds from separate aliquots too. As well as identifying as many D subgroups as possible, it also reduces patient mixups - if you use two separate alequots from separate spins you are likely to pick up a discrepancy between the forward/reverse or two Ds. Use just the one spin and there is a risk of sampling the wrong patient twice and increasing the risk of issuing a false group.

The weak D thing is a separate issue. The second monoclonal D is a 'failsafe' on the grouping if done manually. Not sure where we actually stand with automation. Everywhere I have worked doesn't do two Ds if the analyser is used.

Edited December 1, 201113 yr by Auntie-D

Hello Liz. Sorry it's taken so long to get back to you - I'm mostly out of the office at them moment and not often in front of the screen. Well the situation is this. DiaMed has lots of different cards with a number of different monoclonal anti-Ds that do or don't detect DVI in different combinations so that all European country guidelines are actually covered. There are also cards with polyclonal anti-D. However, for donors, even these strong anti-D reagents won't pick up everything. Many studies have been carried out in the last few years that show that a worrying proportion of donors typing in normal serological tests as D neg with modern techniques actually genotype as D+. Many of these are DEL; some are very weak weak Ds; some are weak partial Ds. The liquid anti-D, which is used on the Coombs IgG cards, not tubes, will pick up some of these as the IAT is a more sensitive method than direct agglutination, even with the strong antisera used - and it is a different clone to any of the clones used in the cards. This is why the liquid anti-D is recommended for donors. Please note, you will still miss the DEL samples. The problem is that no serological method will pick up everything, unfortunately. It depends how far you want to go - or how far your country's guidelines tell you to go. We are starting to genotype all donors who type as Dneg by serological techniques as of next year.