ABO discrepancy

[Liz]

47 yo, healthy blood donor Typed

Anti-A 4+

Anti-B 0

Anti-D 4+

A1 Cells 0

B Cells 0

IS with donor B cells 2+

What is happening?

thank you

Liz

[Liz]

The solution is: The Anti B in this case requires incubation at 4 C to react, and the donor cells were cold when we used them !!

Yes I have resolved it

Liz

[Malcolm Needs ☆]

The solution is: The Anti B in this case requires incubation at 4 C to react, and the donor cells were cold when we used them !!

Yes I have resolved it

Liz

I know hind-sight it as wonderful thing, but I did wonder about that.

:)

[Yanxia]

The solution is: The Anti B in this case requires incubation at 4 C to react, and the donor cells were cold when we used them !!

Yes I have resolved it

Liz

Sorry,my English is not so good. I can't understand whether you incubate the anti-B with the donor cells or the donor plama against another donor cells?

[Liz]

Yes, thank you. Indeed, I felt so happy when I resolved it and the reagent cells reacted 3+ with the donor's plasma at 4 C. I was surprised at how happy I felt! Really glad to know that you get those feelings too ( I am normal !! YES!! ).

Liz :D:D:D

[Liz]

Sorry,my English is not so good. I can't understand whether you incubate the anti-B with the donor cells or the donor plama against another donor cells?

I was doing the reverse blood group typing on a Blood Donor, so I incubated his plasma with Reagent RBCs type B, I did not get any reaction at room temperature; however, when I incubated this tube at 4 C I got a 3+ reaction.

Sorry I mixed you up when I mentioned how I discovered it: I decided to take B+ type blood from the refrigerator and mix it with this donor's plasma, and as I got a reaction, I realized that the cold RBCs helped the donor's anti-B to react.

Now that I re-read what I wrote it is not so clear (I was very happy, happiness does that I guess).

Liz:)

[Malcolm Needs ☆]

I was doing the reverse blood group typing on a Blood Donor, so I incubated his plasma with Reagent RBCs type B, I did not get any reaction at room temperature; however, when I incubated this tube at 4 C I got a 3+ reaction.

Sorry I mixed you up when I mentioned how I discovered it: I decided to take B+ type blood from the refrigerator and mix it with this donor's plasma, and as I got a reaction, I realized that the cold RBCs helped the donor's anti-B to react.

Now that I re-read what I wrote it is not so clear (I was very happy, happiness does that I guess).

Liz:)

I hate to dissipate your happiness, but I take it you also put up a tube of group O cells against the patient's plasma at 4oC to ensure it really was anti-B, and not an anti-I or something like that????

SORRY!

:eek::eek:

[Liz]

I hate to dissipate your happiness, but I take it you also put up a tube of group O cells against the patient's plasma at 4oC to ensure it really was anti-B, and not an anti-I or something like that????

SORRY!

:eek::eek:

hehehe, why was I expecting that? :cool: :cool:

Indeed, I made sure and searched the AABB tech manual (as I said "malcolm will get me for this if not done correctly) and sure enough it said to run a control and I quote:

During testing of patients’ plasma, group O reagent red cells should be included to detect cold autoanti- body or alloantibody.) 2. Incubate all tubes for 30 minutes at room temperature. 3. Centrifuge tubes according to reagent manufacturer’s directions. 4. Gently resuspend cell buttons and examine for agglutination. 5. If no agglutination is observed, incubate tubes for 15 to 30 minutes at 4 C. 6. Centrifuge and examine for agglutination.

As we say here: "I am your student, Malcolm, of course I would do it correctly" :D:D:D

Thank you for your input!!

Liz

[Malcolm Needs ☆]

hehehe, why was I expecting that? :cool: :cool:

Indeed, I made sure and searched the AABB tech manual (as I said "malcolm will get me for this if not done correctly) and sure enough it said to run a control and I quote:

During testing of patients’ plasma, group O reagent red cells should be included to detect cold autoanti- body or alloantibody.) 2. Incubate all tubes for 30 minutes at room temperature. 3. Centrifuge tubes according to reagent manufacturer’s directions. 4. Gently resuspend cell buttons and examine for agglutination. 5. If no agglutination is observed, incubate tubes for 15 to 30 minutes at 4 C. 6. Centrifuge and examine for agglutination.

As we say here: "I am your student, Malcolm, of course I would do it correctly" :D:D:D

Thank you for your input!!

Liz

Liz, I should NEVER have doubted you for a second!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

:D:D:D:D

[Yanxia]

The solution is: The Anti B in this case requires incubation at 4 C to react, and the donor cells were cold when we used them !!

Yes I have resolved it

Liz

Liz, I agree with you that Malcolm's suggestion is right. You need a O cells tube to be control.

Another question, human anti-B have cold reactive antibodies, I prefer to say it is prefer cold environment to reactive. Although it react in 4 celsius or more than 2 drops of serum versus 1drop of cell suspension, these method is reinfroce method, we can get the conclusion from these that anti-B is exist and it is weaker than normal. To explain the reason of weak reaction I think you need to do adsorption and elution test to test the B antigen on this donor's cells.If this is neg, then I think it is antibodies decrease.

[Liz]

Liz, I agree with you that Malcolm's suggestion is right. You need a O cells tube to be control.

Another question, human anti-B have cold reactive antibodies, I prefer to say it is prefer cold environment to reactive. Although it react in 4 celsius or more than 2 drops of serum versus 1drop of cell suspension, these method is reinfroce method, we can get the conclusion from these that anti-B is exist and it is weaker than normal. To explain the reason of weak reaction I think you need to do adsorption and elution test to test the B antigen on this donor's cells.If this is neg, then I think it is antibodies decrease.

Yes, I agree. However, I am still working on introducing Elution/Adsorption into the BB. If you have a procedure I would appreciate if you can share it with me.

ek01@aub.edu.lb

Thanks

Liz

[Yanxia]

Liz, if you have AABB technical menual , I suggest you read it. Sorry , I can't provide it to you directly.

[clmergen]

Isn't it unusual to see weakened reactions in an apparently healthy 47 yr old donor? We usually only have this problem in the elderly or otherwise immunocompromised.

[Malcolm Needs ☆]

Isn't it unusual to see weakened reactions in an apparently healthy 47 yr old donor? We usually only have this problem in the elderly or otherwise immunocompromised.

Yes, I agree it is unusual, but it is not unknown, and, like the famous phrase says, "it is the exception that proves the rule".

:confused::confused:

[clmergen]

So true.

[Liz]

Isn't it unusual to see weakened reactions in an apparently healthy 47 yr old donor? We usually only have this problem in the elderly or otherwise immunocompromised.

You are absolutely right, the blood donor did not fit the usual picture, that is why I was so pleased when I (me, myself and I ) resolved it.

:D

Liz