Low prevelance, Jka antibodies and crossmatching

[Tabbie]

Hi All

Historical A POS (never phenotyped) no antibodies detected. MDS patient, multi-transfused with APOS/NEG units over past 3 months.

Results

Screening cells (using BioRAD 3 cells) +2 positive reaction only with R2R2 (cell II). DAT +2 (IAT method/ IgG/C3d polyspecific)

Panel negative which suggested a low prevalence/frequency/incidence antibody however - crossmatch was positive which led the question was there was another underlying antibody ( a soup of antibodies).

 

Reference Lab Results

Possible Jka by IAT enzyme and non specific enzyme reactions. Now awaiting genotyping.

Advise to crossmatch Rh/K/Jka D-C-E-Jka-

My question is now the patient has returned to group A POS (there was a dual population before with the D type due to the previous transfusions)

is it acceptable to transfuse D+ (as historically RhD+) C-E-Jka- units or could there be a potential D typing anomaly ?

 

Thanks

 

Edited April 16, 2018 by Tabbie
spelling

[Malcolm Needs ★]

I can see no reason why you should not transfused D Positive red cells.

[Tabbie]

Final results

Auto Anti-Jka and nonspecific enzyme IAT ( no requirement to select Jka antigen negative units)

Phenotype E-K- and again Fy GATA mutation negative. 

Has anyone seen an anti-Jka only react by enzyme and not IAT which has not been an auto anti-Jka ?

Thanks

[Malcolm Needs ★]

18 hours ago, Tabbie said:

Has anyone seen an anti-Jka only react by enzyme and not IAT which has not been an auto anti-Jka ?

Yes.  As anti-Jk^a is renowned for being labile both in vitro and in vivo, if you "catch" an anti-Jk^a when it is "on the decline" from reacting by IAT and with "enzyme only", you will quite often see an allo-anti-Jk^a reacting only with enzyme-treated red cells - which is part of the reason why they are just SO dangerous, as we would not detect them in an IAT antibody screen.

[galvania]

and often only with enzyme treated cells tested in an IAT....

 

[Bb_in_the_rain]

On 5/2/2018 at 3:09 PM, Tabbie said:

Final results

Auto Anti-Jka and nonspecific enzyme IAT ( no requirement to select Jka antigen negative units)

Phenotype E-K- and again Fy GATA mutation negative. 

Has anyone seen an anti-Jka only react by enzyme and not IAT which has not been an auto anti-Jka ?

Thanks

Yes. we see so much anti-Jka in this lab (something must be in the water here). Some reacted only by solid phase, some only by enzyme-IAT but not with peg-IAT method. We type the cells and they were Jk(a-) half the time, in which case we recommended transfusion Jk(a-) blood. 

Has anybody encountered this and look into this? 

[Bb_in_the_rain]

Just now, dothandar said:

Yes. we see so much anti-Jka in this lab (something must be in the water here). Some reacted only by solid phase, some only by enzyme-IAT but not with peg-IAT method. We typed the cells by and they were Jk(a-) half the time, in which case we recommended transfusion Jk(a-) blood. 

Has anybody encountered this and look into this?