When I was treated by the haematologist I had pre meds because I had lots of antibodies and had a rash and fever one time. Then I didn't need transfusions for a long time and then I was told they couldn't find the antibodies any more and this new physician doesn't order pre meds.
I wondered about the antibodies because its two different labs. The first lab had a list of 6 antibodies, this new lab says no antibodies. I don't know how that works though, something else to learn about when I'm not so tired.