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No is the simple answer, however, NOTHING in blood transfusion/blood group serology is ever simple!  I would thoroughly recommend you listen to the latest Podcast by BloodBankGuy (Dr Joe Chaffin) and Dr Stella Chou, which may shed light on the subject.

It could well be that your patient has a Partial C (not unlike a Partial D, but not absolutely identical, as the E or e antigen is frequently also involved), particularly if your patient is of a Black ethnicity.  One mutant Rh haplotype that is found not infrequently within the Black populations is (C)cdeS.  With this , the C antigen is not detected by all anti-C reagents and so can appear to be C Negative.  Such individuals also have a mutation causing a partial e antigen, and these people can produce an anti-hrB.  Anti-hrB is relatively clinically insignificant (as opposed to anti-HrB, which is very definitely clinically significant), but mimics an anti-C+e, with the apparent anti-C element being considerably stronger than the apparent anti-e element.

In addition, warm auto-antibodies classically mimic Rh specificities, and this could be such a case (the patient does not necessarily have to be diagnosed with WAIHA).  While the auto-antibodies normally have a mimicking specificity within the Rh Blood Group System, this is not universal.  I remember following a patient for years who was K Negative.  He was never transfused with K Positive blood or blood components, and yet we were able to eluate what appeared to be an anti-K.  This finding was confirmed by Joyce Poole at the International Blood Group Reference Laboratory, who was convinced that it was a mimicking specificity.

I would be really grateful if you could keep us up-dated on your findings - purely because I am nosy!!!!!!!!!

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1 hour ago, noelrbrown said:

Did you detect another (different) antibody in the eluate?  eg. like an anti D ?  If so you may want to consider Matuhasi-Ogata phenomenon....

You may wish to - and then forget it just as quickly.

It has always amazed me how many people know about this, and quote it as a possibility, but so few people, including the greats like Rob Race and Ruth Sanger, have ever seen a convincing case.

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Yes Anti G is very likely, BUT I once manufactured Anti D coated cells using R2R2 cells and was able to elute off a weak anti C along with an anti D, it was an odd antibody as it only reacted in Gel... i still believe it was an example of M-O.

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1 hour ago, noelrbrown said:

Yes Anti G is very likely, BUT I once manufactured Anti D coated cells using R2R2 cells and was able to elute off a weak anti C along with an anti D, it was an odd antibody as it only reacted in Gel... i still believe it was an example of M-O.

Was the anti-D a monoclonal, or a human-derived polyclonal, because, if it was the latter, then that may also had contained a weak anti-G, which could easily have been concentrated in the eluate (and, in addition, gel is very sensitive)?

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3 hours ago, noelrbrown said:

It was  Polyclonal material, I didnt detect the anti C or (G) on incoming inspection but did elute it off R2R2 Cells along with an Anti D.  These days i stick to monoclonals.

Yes, I rather thought so, so it was more likely to be evidence of a weak anti-G in the polyclonal anti-D, than a genuine anti-C (particularly as most anti-C reagents, including monoclonal reagents, believe it or not, are actually anti-Ce, rather than a pure, monospecific anti-C).

Thank you for your reply.

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Are you using the Gamma ELU-Kit ?

#9 in the Limitations talks about the possibility of false positives with strong, high titer antibodies. The saline wash at the start should  remove any allo antibodies in the plasma, but some nonspecific binding can allow some antibodies to linger. The LISS in the wash solution will hold them onto the cells during the rest of the washing steps and they will show up in the eluate with a clear last wash. If your plasma reaction was 4+ and your eluate reaction was 2+ or 1+ then its more likely a diluted allo antibody than an auto anti- C. I've seen this happen twice with C.

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On ‎06‎/‎07‎/‎2019 at 11:45 AM, Malcolm Needs said:

  I remember following a patient for years who was K Negative.  He was never transfused with K Positive blood or blood components, and yet we were able to eluate what appeared to be an anti-K.  

I had a patient like that years ago also.  Anti-K, Kell neg - always had an IgG+ DAT and we always eluted anti-K only even though we transfused him with K= rbcs (for years).  All I could think of was a mimicking ab.

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50 minutes ago, David Saikin said:

I had a patient like that years ago also.  Anti-K, Kell neg - always had an IgG+ DAT and we always eluted anti-K only even though we transfused him with K= rbcs (for years).  All I could think of was a mimicking ab.

I'm glad it's not just me David!!!!!!!!!!!!!

 

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Sooooo, the action of eluting the antibody off the red cell can change the antibody structure, i recently saw this with an Anti Fya.  I dont know the exact mechanism but imagine it has to do with the very low pH causing a change in the epitope.

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21 hours ago, Malcolm Needs said:

I'm glad it's not just me David!!!!!!!!!!!!!

 

We've seen this same phenomenon in a couple of K negative patients over the years.  Do you think this is like the autoantibodies that mimic an Rh alloantibody in a patient negative for the corresponding antigen?

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3 hours ago, Sandy L said:

We've seen this same phenomenon in a couple of K negative patients over the years.  Do you think this is like the autoantibodies that mimic an Rh alloantibody in a patient negative for the corresponding antigen?

Most certainly, this is what Joyce Poole, the Head of Red Cell Serology at the International Blood Group Reference Laboratory told me, and there is NO WAY I would argue with Joyce!!!!!!!!!!!

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  • 2 weeks later...
On 6/20/2019 at 12:42 PM, David Saikin said:

I had a patient like that years ago also.  Anti-K, Kell neg - always had an IgG+ DAT and we always eluted anti-K only even though we transfused him with K= rbcs (for years).  All I could think of was a mimicking ab.

I also had an elderly male like this. The first time he was transfused was the first time he had ever even been in the hospital.

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