Antibodies to low-incidence antigens will be difficult to test for since most screen and panel cells do not have these antigens on the testing cells. Further testing may be needed at a reference laboratory where a larger selection of antibody panels are available to locate cells positive for these antigens.
Suspect an antibody to a low-incidence antigen if:
- AHG crossmatch is incompatible and
- Other causes have been ruled out (positive donor DAT, ABO incompatibility)
Examples of antibodies to low-incidence antigens are: anti-V, anti-Cw, anti-Kpa, anti-Jsa, and anti-Lua.