We had a sample from a pregnant lady of African ethnicity this week.

She is group A, probable rr, K-, with an anti-C that was detected by Bio-Rad (DiaMed) gel IAT and enzyme technique, and by pre-warmed, warm-washed LISS tube IAT at 37oC (about a 3+ throughout).

She also appears to have an anti-e detected by Bio-Rad gel IAT and enzyme technique (about a 1+ throughout), but not by pre-warmed, warm-washed LISS tube IAT at 37oC.

The lady's auto is negative by all techniques, and her DAT is also negative.

What am I suspecting (and it is obviously zebras, rather than horses - as it always is with me!!!!!!!!!!!!!!!!!!!!!!!!!!!!)?

:plotting::plotting:

Malcolm, the lady is African ethnicity, she maybe the type of e+hrs-,The anti-hrs like anti-e but it will not react with the rare type e+hrs-. But this antibody has caused HDN.

Malcolm,you are always my teacher in this forum,if it is not Anti-Hrb or Anti-Hrs,please tell us what are you suspecting ?

I'll give it a couple of days, but you are both thinking along the right lines.

I suspect you don't know the answer and are hoping someone will give it to you!

Hi Malcom, how are you? and in answer to your question some time ago... yes it is Simon from BGRL etc

Will be in touch shortly.

************** cheek!

HI Simon,

Great to hear from you.

No, I don't know for certain what it is, BUT I do know for certain what I think it is!!!!!!!!!!! Two very different things.

Please keep in touch.

Malcolm

I'm with Shily & Abdulhameed Al-Attas on the strong possibility of Anti-hrs or Anti-hrB.

Several years ago we had a female African-American patient who made Anti-hrs. She also made Anti-E!! (Those zebras do cross our paths every once in a while, don't they?)

Donna

I'm with Shily & Abdulhameed Al-Attas on the strong possibility of Anti-hrs or Anti-hrB.

Several years ago we had a female African-American patient who made Anti-hrs. She also made Anti-E!! (Those zebras do cross our paths every once in a while, don't they?)

Donna

Okay, I suspect it is a very weak anti-hrB.

Shily could be right, in that it could be an anti-hrs, but I don't agree that it is (yet) the anti-HrB of which Abdulhammed Al-Attas speaks.

A weak anti-hrB quite often starts out as an apparent anti-C (or anti-Ce) accompanied by a very weak anti-e, which then gets stronger and stronger, and the anti-C (or anti-Ce) becomes indistinguishable from the anti-e in terms of strength. If it goes on to be a full-blown anti-HrB, then the antibody also reacts with R2R2 and r"r" red cells as strongly as it does with other "normal" Rh phenotypes, but does not react with D--/D--, D../D.., DCw-/DCw- or Rhnull red cells.

I firmly believe that there is a sort of continuum in terms of weak anti-hrB, strong anti-hrB and true anti-HrB.

I'm just hoping that, with our patient, she does not go on to make an anti-HrB - transfusing her would be a problem, and there is now evidence that it can cause severe HDN.

Well done all of you!!!!!!!!

Learn things more from your post, Malcolm. And thank you.

Maybe from her relatives you can find compatible blood.

At the moment, as the antibody is so weak, we are planning to give the lady rr blood, should she require a transfusion.

Hey Malcolm,

Happened to read this posting, was wondering if the red cell typing for e antigen looked 'funny'? Thanks

Emergency room

Okay, I suspect it is a very weak anti-hrB.

Shily could be right, in that it could be an anti-hrs, but I don't agree that it is (yet) the anti-HrB of which Abdulhammed Al-Attas speaks.

A weak anti-hrB quite often starts out as an apparent anti-C (or anti-Ce) accompanied by a very weak anti-e, which then gets stronger and stronger, and the anti-C (or anti-Ce) becomes indistinguishable from the anti-e in terms of strength. If it goes on to be a full-blown anti-HrB, then the antibody also reacts with R2R2 and r"r" red cells as strongly as it does with other "normal" Rh phenotypes, but does not react with D--/D--, D../D.., DCw-/DCw- or Rhnull red cells.

I firmly believe that there is a sort of continuum in terms of weak anti-hrB, strong anti-hrB and true anti-HrB.

I'm just hoping that, with our patient, she does not go on to make an anti-HrB - transfusing her would be a problem, and there is now evidence that it can cause severe HDN.

Well done all of you!!!!!!!!

Malcolm, do you have a follow up. What was transfused and how did it go? Moreover, did she deliver and what happened, HDN is a risk.

Thanks

Thanks for sharing an interesting case...

Hi Malcolm,

I am new at this forum so my repley is a little late.

From the DNA work of the france group I understand that the HrB neg fenotype is always expressed together with an r's allel or with a DIII type 5. (we recently had such a case) Yout patient is rr and therefore not fitting.

I agree that the Ce like pattern fits more with hrb/Hrb but if the anti C is realy an allo antibody than the hrs/Hr pattern of anti e that is stronger reactive with f positive cells can no be seen, so an anti hrs is still possible.

Although I am a true serologist, I think that a DNA investigation is the most informative.

Peter

Strangely enough, I am on-call tonight dealing with another such patient, only this time the Rh phenotype is an apparent R1r - although I strongly suspect that she is an Ro/r'S.

She has an antibody reacting with all e+ red cells by enzyme, except R2R2 and her own enzyme-treated red cells, and again, the reactions with the C antigen are stronger than those with the e antigen.

Just to complicate matters further, she has an anti-S (but, of course, this was easy to see, as it was reacting by IAT).

I agree entirely with you about genotyping being the way forward for this kind of patient.

So what did the pre-warming have to do with it in your first post? I assume the pre-warmed LISS did not react with the e cells just because of the weaker reactivity in a less sensitive technique, but maybe this is something I don't know about these weird antibodies I have never seen. But why did you do a pre-warmed technique if you did not have a cold agglutinin present?

It is simply that we often use a pre-warming technique simply because it is less sensitive, as can help us to sort out multiple antibody specificities, which we can then prove by the more sensitive techniques.

I should add, perhaps, that, in extreme cases, I am quite happy to use the old transluscent white tile IAT (I can just see the looks of shock going around the world from those who know what I am talking about, and the head scratching of those that don't) as, sometimes, you can see the different specificities "coming up" positive at different rates (and the same goes for the Chown capillary IAT).

I will then go on to confirm these with more sensitive techniques.

Never be too ready (or too proud) to abandon old techniques; many of our fore-fathers in the profession were a canny lot!

:disbelief:disbelief:disbelief:disbelief:disbelief

Edited September 5, 201113 yr by Malcolm Needs

Never heard of Chown capillary IAT & transluscent white tile IAT .

Malcolm, when you have a time, could you please brifly tell us about those techniques?

Never heard of Chown capillary IAT & transluscent white tile IAT .

Malcolm, when you have a time, could you please brifly tell us about those techniques?

I certainly will, but a whole load of my staff have disappeared off to the Annual Scientific Meeting of the British Blood Transfusion Society this week, so time will be limited. I may have to do this next week.

Never heard of Chown capillary IAT & transluscent white tile IAT .

Malcolm, when you have a time, could you please brifly tell us about those techniques?

Age must be galloping up on me, as I've just remembered that I have already done this!

If you go into the "Library" tab at the top of the page, and then go to the "Educational Material" tab and hit that, there is a list of some material that I (and others) have submitted to this site. About the fourth or fifth (?????) subject down is an essay entitled "A Brief (and Incomplete) History of the Antiglobulin Test". In this, you can not only find a brief description of these techniques, but there are also photographs (a bit fuzzy, I'll admit, as I am no David Bailey) of what the resulting tests look like.

If you cannot find this, if you can give me an email address (via private messaging), I will email you the article - if I can still find it amongst the mess I laughingly call my computer files!!!!!!!!!!!!

Very interested Malcolm, and Dr Coombs' picture is there!