Yanxia

Because of the normal B antigens on the cells, so we can see strong reaction on MF with anti-AB.

Brilliant post StevenB. I just out of curiosity, you said the after-adsorption plasma reactived with IAT, and had a titer of 16,384 , which is very high, but non reactive with PEG IAT. So interesting. If my understading of English is right

In my opinion, if we cannot select an antigen neg reverse cells, there are things we can do, it is adsorbing the plasma/serum using pooled O cells, then do the reverse typing, to get a neat anti-A or anti-B result.

Would you please explain why we can different the maternal blood and fetus's blood by using NaOH? Thanks!

Thanks for your advice. We often see neg DAT results with ABO HDFN in our work.( Because the A B antigens on the newborn red cells are weak ) You are right that I need an eluation result to support the HDFN . As to anti-A1, we got 3 pos with A cells and 3 neg results with O cells. And yes, maybe due to infection the baby's cells can be polyagglutinatable, just cannot interfere with the plasma reaction with donors and screen cells.

The baby's and his mom's plasma screen test is neg , and baby's plasma reacted with three different A donors' cells, so I suspect it is anti-A( anti-A1).

I have met two cases of babies. Their plasma had anti-A or anti-B, as their correspond type. And the doctors had not seen HDFN signs clinically. We found it through crossmatch.( we issue same type blood to infant have no ABO HDFN).

The baby's DAT is negative. Yes, the baby has anaemic and very bad sicked on the machine to help him breath. He has very servere infection, maybe this cover the symptoms which shows HDFN. And ABO HDFN is always mild. The jaundice is normal.

My experience and knowledge in bloodbank is so little. This is the first time I met an warm reactive anti-A1 and which can pass the placenta barria. It is new to me.

Sorry , I cannot sure about that. Is there IgG anti-A1 exist in subgroup people?

I just encounter a 3 days old baby, his type is A pos, and has anti-A in his blood. His mom is A subgroup B. If the baby have anti-A, it is IgG. Is it possible an A sub B produce IgG anti-A? Thanks for your advise.

If the reverse reaction with B cell was a typo, I agree with Malcolm, it is an anti-A1or anti-ALeb. As for the negative saline replacement result, since the neat plasma reaction is weak, it maybe weaken by the test method.

If the patient has received transfusion, the transfused antigens pos cells can cause the autocontrol mixed field positive, and when the antibodies are against some low prevalence antigens, then the reaction with screening cells and donor cells can get a neg reaction. Or some drug induced antibodies can cause this kind of reaction because they are drug dependent.

Sorry, I am stubborn as for this major, I guess I have caused noise here. If the reverse type show antibody then it is ok, why would we call 2+ or more to be normal and less to be weak and then to invest it? For ABweak patients, I still think it is safe to transfuse them with AB plasma, even they have their anti-B ,but the anti-B is not the same as O and A people's, it is not react with its own B antigens, but the transfused anti-B can, that is why the weak B antigen can be detected with some strengthen method. We will identify this kind of weak antigen with add more serum ,4 degree C incubation or adsorption/elution test, not genotype it, which is not so expensive.

I totally agree with you about the transfusion, galvania. And I think we should call it AB subgroup if there are weak B antigens, rather than A group, because sometimes they will need plasma and something contains plasma.

In the case of ABel, the forward typing is not shown B antigens, and reverse typing with weaken anti-B.

This is my understanding, maybe it is not correct, just want to share it here, and correction is always welcomed. If the reverse typing is weak than 2+, it means the immediate spin result, the antiboies are weaker than normal, subgroup or weaken antiglobulin. Even we incubate or change the reaction temperature or add more serum, it shows 2+ or stronger reaction, it is still weaker than normal typing( not so exactly, because my Enligh is not good). Can we call it normal when we incubate or 4 degree C treaction 2+, no. These are just ways to strengthen the reaction. Which is somehow like we do weak D test, can we call it normal D when we get pos result in anti-antiglobulin test.

I agree with you if transfusing RBCs, on the other hand, plasma transfusion, I think it is safe to test if the weak B antigens exist or not.

I would add more antisera and/ or incubate the forward test at 4 degree C to see if there are B antigens here, if negative then adsorption and elution on the forward B antigens to see if it is existed. The most important thing as Malcolm mentioned above keep a group O cell as negative control. If all the above tests are all neg, then I will call it A type with weaken anti-B.

I think washed out the plasma and freed K+ is safer to newborn, and it is not too expensive, just 20 yuan more than the packed cells. And if do the anti-A, B titre in the packed cells is also time consuming and money consuming. Just my personal opinion.

How about give them the washed RBCs?

Maybe choloroquine phosphate can help to remove the IgG antibodies on the cells surface. And heat elution (45 degree C 15 min or 56 degree C 10 min) can do some help to remove IgG antibodies, but not as effective as to IgM antibodies.

yes, it can. Because the PH of the salin is in larger span than the diluent which maybe PBS .And the reaction's best PH is in the diluent.

I think we'd better drop it as wast or wait until there is time to test it.

why the frozen/thawed AB plasma not react with the treated cells?