catm

I don't know for sure but there was nothing on her referral suggesting she had received treatment for any medical conditions. 

Yes ,the neutral cards do not contain any anti globulin reagents however I thought that if an Rh antibody was present this would be enhanced by the enzyme techniques? The current  BCSH guidelines for compatibility testing  state that is acceptable to exclude Rh antibodies using validated techniques with enzyme treated cells. That being said, if an antibody was detected by IAT showing Rh specificity I would not exclude its presence even  if it was negative by enzyme technique.
In this case the reactions were variable but never more than a 2+ reaction, sometimes there in both techniques , and sometimes only by IAT. In the most recent sample, the enzyme is negative and the only reactions by IAT were with an R2R2 in the screening cells and with the R2R2 in the panel. (both 1+ reactions). 
It is also possible that she has had a prophylactic anti-D injection that has not been documented in her notes. As far as management of the pregnancy is concerned anti-D prophylaxis will be recommended at present.
 
 

Yes ,the neutral cards do not contain any anti globulin reagents however I thought that if an Rh antibody was present this would be enhanced by the enzyme techniques? The current  BCSH guidelines for compatibility testing  state that is acceptable to exclude Rh antibodies using validated techniques with enzyme treated cells. That being said, if an antibody was detected by IAT showing Rh specificity I would not exclude its presence even  if it was negative by enzyme technique.
In this case the reactions were variable but never more than a 2+ reaction, sometimes there in both techniques , and sometimes only by IAT. In the most recent sample, the enzyme is negative and the only reactions by IAT were with an R2R2 in the screening cells and with the R2R2 in the panel. (both 1+ reactions). 
It is also possible that she has had a prophylactic anti-D injection that has not been documented in her notes. As far as management of the pregnancy is concerned anti-D prophylaxis will be recommended at present.
 
 

Thanks for your responses and suggestions.
In answer to your questions. The cells appear to auto agglutinate using CAT - all wells positive in ABO and Rh cards but typing by tube was fine- no false positive reactions.
We used NHSBT adsorption cells which are enzyme treated. We did the adsorption 6 times.
We do not have access to chloroquine so can't try removing the auto antibody.
 
The direct testing at RT was done with the neat unadsorbed plasma. The only information I have about the patient is that they have macrocytic anaemia.
 

Thanks for that. It makes it a bit clearer in my head and happier with  the selection of blood. (Sorry about the typo -  I realise Oh would need H neg and not I neg ! )

We have a group O patient who has irregular results by Ortho  IAT. 14 out of 22 cells are reactive (+) to 2+ reactions (all normal antibodies ruled out) The auto is negative and DAT is  neg, In the RT direct tube tests all panel cells plus Oi cord sample are positive 2+ but the auto control is negative. Could this be an anti-H or would you expect stronger reactions?  We do not have anti-H available to test the patient. Also wondered about anti-Vel? 

Hi Malcolm
Thank you for your answer. We are a reference laboratory and have fully investigated the ABO anomaly  serologically using the techniques available to us. ie. Ortho and BioRad ABO reverse and newborn cards/cassettes. Tube ABO at 4°C and RT. In the past we would have done absorption/elution techniques to look for the presence of the B antigen and we may do this once we receive further samples but I am not sure how reliable this technique is . I am interested in what further tests you would perform to try and conclude the ABO.