Ah! Brenda! I am deeply grateful for this thread. I have been preaching this for so many years and I do dearly hope that it has sunk in to those Medical Laboratory Scientist candidates and the pathology residents who have been in my care. It sounds as if you are succeeding in your efforts. Probably the most difficult history problems arise among sickle cell disease or Thal Major patients in a large urban area. As their rate of isoimmunization is higher than "normal" patients, you are not likely to encounter such a patient without one or more antibodies. The trouble is that they tend to move among hospitals, either because they are searching for better treatment options or because their pain control isn't adequately addressed. And of course they don't tell anyone upon admission what kind of antibodies they may have, should they know, and before long, through no fault of your own, you are staring down the barrel of a DHTR. A while ago, what was then known as the Chicagoland Blood Bank Society was looking into the possibility of keeping a database of such patients, with their various and sundry antibody problems, (and their phenotypes) and to share them among the area hospitals. While it never came to fruition, and perhaps these days we might have to run into some interference with HIPAA guidelines and regulations, it is certainly a good idea. I envy the network hospitals that share this data. With respect patient cards that identify their problems: For a number of years, for those patients who suffered from DHTRs caused by the usual evanescent antibody specificities, we used to provide MedicAlert bracelet/necklace applications to the attending physician along with the transfusion reaction report. It was an idea I had hoped would assist other blood bankers in the metropolitan Chicago area. I finally gave up after a pending surgical patient phoned me from our intensive care unit, and told me that she was wearing such a bracelet. She had told several residents that she had a "compatibility problem" but they told her not to worry about it because "the transfusion service at our hospital was so good" that we would figure it out. So she read off "anti-Jka" from her bracelet. It was our bracelet, and the antibody problem was in our computer system, but her antibody screen was, indeed, negative. If she had been admitted elsewhere would the other physicians have been equally cavalier and dismissed this information?