Within the last two months, we have received two patients who, no matter what we do, can not get a valid type. Same issue with both. Forward typed as an A back typed as an O. The problem was that they both have a STRONG cold interferring with the reverse type. The first was a CAS probably with anti-I and second had a strong anti-M. No matter how long we prewarmed these patients we still had reactions on the A1 cells in the reverse typing. (the first patient I even went to the unit myself with prewarmed tubes in a warm water bath and kept the specimen warm throughout the entire testing. It still didn't help.

Everything we could do had been done and we do testing that borders a reference lab and a normal basis....which makes finding experienced blood bankers even harder...but thats another problem.

Both patients had been send to our reference lab, both results came back as Apos. When asked about the reverse, "oh we didn't have any problem with the reverse, just prewarm and you'll be fine"......the Echo picked up on it in the reverse, 1st pt 2 BB techs and myself worked on her, second was over a weekend but I know of 2 for sure BB techs worked on him and they are experienced too.

Now to my question

I can't help but to question the reference lab when they claim to have had no problems when so many good experienced techs and using multiple methods could never get it to work.

Anyone know of an explaination to this? I believe the reference lab uses Gel. Maybe that doesn't pick up colds but the Echo isn't suppose to either....but when they are as strong as these two were, it will pick it up.....does the GEL not?

To the anti-M, the ref lab's A1 cells may not express M antigen. As to the I antigen, I don't know whether the specimen send to the ref lab has been set in fridge for a long time span, if it is, then the anti-I (in CAS it is autoantibody) will adsorbed by the patients own cells ,then the free antibody is few.

We would probably use cord A cells at 30oC for the reverse grouping with a patient with such a potent auto-anti-I.

As shily says, for the patient with the anti-M, we would use M- group A1 red cells in the reverse group.

I agree with both Shily and Malcolm.

(We have found that the Echo usually doesn't pick up cold autoantibodies, but sometimes it does.)

Donna