3. Do the results of the initial antibody screen (shown below) support the presence of the identified antibody?
No: All 3 screen cells reacted in the initial screen. Upon review, however, only Screen Cells 1 and 3 were Jk(a+); Screen Cell 2 reacted but was Jk(a-).
This anomalous result was investigated by a reference laboratory. It was discovered that the patient had anti-Rd, an antibody to the low frequency antigen Radin (Rd). By chance, Screen Cell 2 was Rd-positive. Radin has a frequency of less than 0.5% in several populations tested.
If the screen cell manufacturer was notified, they would likely confirm that the cell was Rd-positive, make their clients aware of it, and document it in future antigrams.