Hi

a donor came to our blood bank , and when i preformed the forward grouping he appeared as an AB+ group . on the other hand on the reverse group he is O group .

forward group: anti-A 4+ , anti-B 4+, anti-A1 4+ ,anti-D 4+

reverse group :A cell 4+, B cell 4+

waiting for your replies

I would bet he has a Positive DAT! If so, you can not report ABO/Rh until you get DAT negative sample. Most likely (but not definitively)the patient is Gr O, but Rh is mystery.

I would bet he has a Positive DAT! If so, you can not report ABO/Rh until you get DAT negative sample. Most likely (but not definitively)the patient is Gr O, but Rh is mystery.

Therein lies the problem with such individuals!

Given that the grouping reagents are almost certainly monoclonal, I would not be surprised if this individual is group AB, D+, with a "cold" reacting auto-antibody, or something like an anti-M, an antigen that may well be expressed on both of the reverse grouping red cells, or, given that the individual may be an AB, an anti-H or anti-HI.

My advice, like Bill's, is to perform a DAT, but using monospecific reagents (i.e. an anti-IgG and an anti-C3d, and perform an elution, if the IgG is positive). Also to perform a full panel at 4oC, 20oC, 30oC and (strict) 37oC. If none of these panels resolve the situation, try using a panel of group A1 red cells (you will, obviously, have to "construct" this panel yourself).

Lastly, you could perform adsorption and elution studies with anti-A and anti-B.

Come what may, I think that this donor will need to be, at least tempoarily, excluded.

Did you run an immediate spin auto-control to rule out panagglutination?

How about your Rh control/or control tube. That result would also be helpful.

Hi guys

Thanks for your replies , I already did the DAT and it was negative . I also run the forward , and reverse grouping on the Gel system . The result of the forward was AB+ . I tested the reverse on two different type of A cell, and B cell I prepared in our blood bank and the result was negative on both type of cells.

Note: I used monoclonal igG and anti- C3d

Hi guys

Thanks for your replies , I already did the DAT and it was negative . I also run the forward , and reverse grouping on the Gel system . The result of the forward was AB+ . I tested the reverse on two different type of A cell, and B cell I prepared in our blood bank and the result was negative on both type of cells.

Note: I used monoclonal igG and anti- C3d

lord_shadi,

Does the Gel system used have an Rh control component? When you repeated the reverse type did you utilize the same Gel system, or an alternative testing system, or both? And lastly, can you give the specifics of the A and B cell preparations used? Thank you in advance for any reply.

I choose 2 units of group A and B and I washed the cells 4 times . I used the same Gel system . I used the cards specific for grouping.

Hello Lord_Shadi - in your later post you said that the reaction with A cells and B cells was negative - which is what it should be. Is that just a typing error or has the problem now resolved itself? In other words, the original false positive results in the reverse group were not reproducible? I presume you are working manually? If so, my guess is that the firs incorrect results were simply due to operator error somewhere along the line.

For rravkin - yes, the gel cards do have a ctl well. So Shadi - was the ctl well negative?

If you are using monoclonal gell cards, a positive DAT would not give false positive reactions in the grouping cards unless the DAT was positive due to cold agglutinins

Hello Lord_Shadi - in your later post you said that the reaction with A cells and B cells was negative - which is what it should be. Is that just a typing error or has the problem now resolved itself? In other words, the original false positive results in the reverse group were not reproducible? I presume you are working manually? If so, my guess is that the firs incorrect results were simply due to operator error somewhere along the line.

For rravkin - yes, the gel cards do have a ctl well. So Shadi - was the ctl well negative?

If you are using monoclonal gell cards, a positive DAT would not give false positive reactions in the grouping cards unless the DAT was positive due to cold agglutinins

Hi there

Sorry I forgot to mention that i did the grouping manually by using the tube technique , however, I ran the test two times and I'm sure that I did it correctly . But I did it with the Gel system and the result was as I mention in my previous post . I run control the card and it was negative for both type of cells.

Hi there

Sorry I forgot to mention that i did the grouping manually by using the tube technique , however, I ran the test two times and I'm sure that I did it correctly . But I did it with the Gel system and the result was as I mention in my previous post . I run control the card and it was negative for both type of cells.

What about the reverse A1 and B cells is T active, so they will react with all serum except newboren's.

Or this donor has antibody against the preservation of the reverse cells, wash it before test may resolve this problem.

Hi there

First off all I want to say that I ran the auto and the result came positive. I believe I have to do adsorption to identify the autoantibodies. However, we called the donor ane I collected a blood sample. I did the grouping and I come to conclude that the donor is a Cis AB. Because of the reaction I get is exactly typical to the Cis AB. Now my question is that is it ok to use his blood product.

Shadi,

1. I do not understand what the results of the reverse grouping are? Positive or negative?

2. How did you come to the conclusion that "the donor is a Cis AB" ?

May I ask the donor's nationality?

In my memory CisAB will not react with anti-A1, and the reverse grouping is not like this, not so strong except at the same time has other cold antibodies.

Shadi,

1. I do not understand what the results of the reverse grouping are? Positive or negative?

2. How did you come to the conclusion that "the donor is a Cis AB" ?

Dear Liz

The forward grouping is Anti- A , Anti-B , Anti-D are all positive 4+ .the reverse group i got a weak reaction with B cell and negative reaction on A cell.

The nationality of the donor is Pakistani .

In my memory CisAB will not react with anti-A1, and the reverse grouping is not like this, not so strong except at the same time has other cold antibodies.

Dear shily

In my first post I mention that in the reverse reaction both of A, and B cells were strong positive . However, I did called the donor and repeated the grouping of both forward and reverse and the result was AB+ for the forward, on the other hand , the reaction of A cell was negative , and B cell was weak positive 1+.

Note: the grouping was done on Gel system

Thanks

In Korea cisAB is relatively common, I am not sure about Pakistan. It would be interesting to know.

What do you plan to do in order to confirm CisAB?