Previous Anti-HRb - should I be worried

[janet]

We have history comments on this 92Y Caucasion female patient stating she had an Anti-HRb identified by our reference lab in May 1989 (screen was negative April 1989 prior to giving her 3 packed cells). Methodology then was saline IAT.

Antibody screens were negative on July 24th, August 2nd and August 14th of this year (gel technology). We gave her 2 packed cells each of these occasions.

Yesterday we received a request for 2 more packed cells, after a night of testing we think she has formed an Anti-S (1+ reactions with Ss, 2+ with SS), E (2+)and an "unidentified" that reacted weakly with 5 of 9 E-S- panel cells and 3 of 4 E-S- units.

Does the historical antibody seem plausible - should I worry?

[Malcolm Needs ☆]

We have history comments on this 92Y Caucasion female patient stating she had an Anti-HRb identified by our reference lab in May 1989 (screen was negative April 1989 prior to giving her 3 packed cells). Methodology then was saline IAT.

Antibody screens were negative on July 24th, August 2nd and August 14th of this year (gel technology). We gave her 2 packed cells each of these occasions.

Yesterday we received a request for 2 more packed cells, after a night of testing we think she has formed an Anti-S (1+ reactions with Ss, 2+ with SS), E (2+)and an "unidentified" that reacted weakly with 5 of 9 E-S- panel cells and 3 of 4 E-S- units.

Does the historical antibody seem plausible - should I worry?

Well, the first thing to say is that, whilst I wouldn't question the findings of another Reference Laboratory (it would be unprofessional so to do), I have never heard nor read of a PROVEN anti-HrB in a Caucasian individual. That does NOT mean that there is nothing in the literature; it simply means that I have not come across it. Most examples of anti-HrB have been described in the Black population, although I have read about an example in the Chinese population that caused HDFN (and they successfully exchange transfused the baby using ABO incompatible blood!).

That having all been said, we have successfully transfused patient's with a weak anti-HrB with HrB+ blood (with strong anti-HrB, we honour the antibody and transfuse either HrB- blood or, if we can't get hold of it Rhnull blood).

Given that this patient is 92-years-old, so her immune system will not be working at its optimum level, and the (apparent) anti-HrB seems to have disappeared, it should be "safe" to transfuse cross-match compatible blood (or even cross-match weakly incompatible blood) with IVIG cover.

THIS IS ONLY A PERSONAL OPINION.

[Mabel Adams]

I think National Geographic recently sponsored DNA testing for a large group of Americans and had them actually gather when they gave them their results. They grouped them by the ethnic group/race that their DNA most connected them to. The people in the groups looked nothing like each other and many had no idea they shared a genetic link to the group they ended up in. There were people that looked Caucasian in the African group and every other combination imaginable. I know that at most hospitals I have worked at race is recorded by the admissions clerk eyeballing the patient (unless they provide Indian Health insurance or state some particular race). So several grains of salt may be necessary.