ABO/ Rh Testing- MTS gel vs. Tube

[Liz]

Hi Dave,

Now things make sense, thats why I don't and you do perform the AHG for D neg.

Ok! Great, thanks for that.

[Liz]

Oups, are you in the US or UK, Dave?

[David Saikin]

US of A

[ABQ bloodbanker]

Hi Denise,

Do your gel cards contain the anti-DVI?

Do you have different cards for donors, patients and newborns?

Thanks.

Liz,

We only have one type of anti-D, and it is used for all of the above. Supposedly does not detect DIV....

[David Saikin]

There is only one distributor of gel cards in the USA right now (Ortho). This will change next year when their proprietary rights expire. BioRad (aka Biosite/Diamed) will market here next year with their entire gamut of cards (which is very extensive). I have used the Diamed DAT card (off label of course as it is not approved for use by the FDA). I see that Shily says China is making their own cards now so . . . who knows what the future of gel testing in America holds. Should be exciting.

[Liz]

I use Diamad and they have automation which I am considering. They have a large variety of cards. They even have ABO/RH cards with one column that has the anti-DVI and one without the anti-DVI in the same card. I like the quality of course or else I would not use it.

Thank you Dave for explaining that you do not have this option, I was wondering if I should perform the AHG on D negs, I see that I am covered.

[David Saikin]

Liz - do you use the Diamed DAT card? ( it is the one with anti-IgG,-IgM,-IgA,-C3c,-C3d, and a Ct tube). If you do, I was wondering how you control the IgM/IgA tubes.

[Eagle Eye]

Aakupaku (I love your name by-the-by) - when we get an AB+ cord, we rerun it using an ABD Reverse card (sans the backytype). The weak D we run in the IgG gel card with pt cells and tube anti-D - - - weak D only on Rh= cords and donors.

I am thinking!!! Is weak D testing necessary on CORD? Only cases where you need to determine if KB need to be done instead of Fetal screen???

We confirm CORD blood type with tube so I guess I do not need to run weak D on Gel... Our tube method we carry through weak D testing...

I know where you are coming from David---Std. 5.20.2 (3) ...weak D testing is required when the test for D is negative....(26th edition)

Yes...I answered my own question...:)

[aoliveg]

Hi Liz

Can you explain me the type of your Diamed Products, and your POEs for ABO/RhD typing??

[Liz]

Hi,

What does POE stand for?

[Liz]

Liz - do you use the Diamed DAT card? ( it is the one with anti-IgG,-IgM,-IgA,-C3c,-C3d, and a Ct tube). If you do, I was wondering how you control the IgM/IgA tubes.

Yes I use that card. It has a control in it. But I think you mean how do I test to see if the IgM, IgA in the cards are functioning (QC).. I dont. I have just contacted the local rep to see what the company says.

Thanks for pointing this out.

(To test for IgG I could use Coombs control cells).

[David Saikin]

Let me know what the rep says . . . I would hate to have to buy anti-IgM and anti-IgA to sensitize cells. I did find an anti-IgM DAT in a pt with a strong anti-I. I expected to find comlement components on the red cells but IgM was a good 2+.

[aoliveg]

I need to know your workflow to:

ABO/RhD Typing for patients and donor using DIAMED Gel device

[Liz]

Let me know what the rep says . . . I would hate to have to buy anti-IgM and anti-IgA to sensitize cells. I did find an anti-IgM DAT in a pt with a strong anti-I. I expected to find comlement components on the red cells but IgM was a good 2+.

Looks like they have sensitized cells with Anti-IgM, Anti-IgA etc.. I have asked for a quote and a ref saying it is required and how often. Will keep you posted, Dave.

Liz

[Liz]

I need to know your workflow to:

ABO/RhD Typing for patients and donor using DIAMED Gel device

If you could clarify what you are looking for? Is it the type of cards I use for each different population?

[cajcpsbb]

The Best of Both Worlds in my opinion is to use test tube for ABO/Rh and gel for antibody screening. I have been in the medical field for 34 yr working in Lab Medicine, Heart Surgery, and now back to Lab Medicine. I am well versed on what technology WAs and what it now IS. Both have their advantages and disadvantages but if money were no object, this is what I consider the best testing scenerio for patients. I am concerned that "what is best for the patients" is not looked as it used to be.

Edited September 18, 2010 by cajcpsbb

[KBBB]

We did not perform a formal correlation, but when we had known weak D's or when we do get a 1-2+ reaction, we repeat it in tubes and it is negative at IS and 3-4+ at IAT phase. We've probably seen over 20 of them in the last 2 years.... not a whole lot, but enough to add to our procedure that if you see a weak anti-D reaction in gel, call them Rh Negative...

Is this the standard out there? I don't have the Ortho procedure in front of me, but do they say to call a patient 'Rh D negative' if the reaction is less than a 3+ reaction on their ABD cards? Do others call any reaction for gel D, ' Rh D positive'? ...or do you then do a tube Rh and use the tube result for your interpretation (wk D not required for recipient testing)? If the D typing in gel is more sensitive, but for those few patients who are wk D we ignore the more sensitive aspect and revert to the less sensitive tube test, do we use the logic that it only affects a small number of patients? We have to use the gel cards (reagent contract), and will also have tube testing available for unit retypes and backup patient testing. Our transfusion service will only be serving an adult population.

[Liz]

There are gel cards for patients that won't detect weak D and for newborns and donors that will.

One way to do things (if you don't have the DVI cards) if you have a suspected positive but "weak" D by gel, perform the tube, if neg , it is a weak D, because it will show by AHG.

[Malcolm Needs ☆]

If it were only that straightforward Liz!

There are now over 150 genetic variations to the D antigen (some of which are, admittedly silent), but the only real way of telling apart a Weak D and a Partial D is at the genetic level (and even then, some of the Weak D types do produce a true alloanti-D).

:omg::omg:

[Liz]

Oh No Malcolm, I certainly was not trying to differentiate weak D from partial D. Me?! Never at the serological level.

No, I was just trying to say when to consider a D as "weak or partial" differentiating it from the fully expressed D.

[Malcolm Needs ☆]

Oh sorry Liz; my mistake entirely.

[PHYLLIS]

Hi Liz,

Since Gel is more sensitive and it picks up Du Pos types, do you do an indirect coombs on a negative D result in tube for the retype?

Thank you,

Phyllis

[Liz]

Hi Liz,

Since Gel is more sensitive and it picks up Du Pos types, do you do an indirect coombs on a negative D result in tube for the retype?

Thank you,

Phyllis

Yes we do the AHG on tube for retypes.

Liz

[hughes]

The provue cannot detect weak D. For pregnant patients, do most places do a tube test for weak D or do you accept the Rh negative result to protect against fetal bleeds. The weak D in the tube method could be from a fetal bleed in which case the weak D result would be inaccurate. What policy do most places follow in this situation?

Thanks

[Liz]

Good point. Perform the tube test for weak D, you base your judgement on medical history and perform the Kleihauer Betke test. If you don't have the mom's initial blood group in your data base, give RhIg if still in doubt.

Liz