Normal Survival of Incompatible Red Cells in the Presence of Anti‐Lua

A case is reported in which incompatible Lu(a+) red cells survived normally in the presence of anti‐Lua as indicated by hemoglobin‐hematocrit determinations and by differential agglutination. This fact was later confirmed by Cr51 tagged cell studies. Sensitization apparently existed prior to transfusion although it was not detected by crossmatching at that time. The direct non‐gamma antiglobulin test became positive and a potent antibody was produced which reacted well at 37 C. and in albumin, enzyme, and antiglobulin tests. The findings in this patient are discussed in the light of previously reported cases.