If a woman's antibody screen is positive before a transfusion, which antibody is likely responsible for the positive result based on the panel provided?

In the context of a positive antibody screen before a transfusion, the presence of specific antibodies indicates potential incompatibility with donor blood. When evaluating the possible antibodies, anti-K (Kell antibody) is particularly noteworthy due to its clinical significance and the frequency with which it is encountered.

Anti-K is known for being a common IgG alloantibody that can cause hemolytic transfusion reactions if incompatible blood is administered. Furthermore, the Kell antigen is present on a large portion of the population, making it highly relevant in transfusion medicine. The fact that this antibody can lead to severe transfusion reactions underlines its importance when selecting compatible units for transfusion.

In contrast, while antibodies such as anti-D, anti-Leb, and anti-Jb may also be detected, they are not as commonly associated with severe transfusion reactions. Anti-D primarily concerns Rh blood type and typically only becomes an issue in certain clinical scenarios like Rh incompatibility in pregnancy, but it is less frequently the sole cause of a positive screen in transfusion settings.

Thus, the likelihood of anti-K being responsible for a positive antibody screen is higher, making it the appropriate choice in this scenario. The clinical significance and frequent identification of anti-K in pre-transfusion testing justify its