Anti‐ D alloimmunization after D ‐incompatible platelet transfusions: a 14‐year single‐institution retrospective review

Background A small, but immunogenic dose of red blood cells ( RBCs ) may be contained in apheresis platelets (PLTs). Attempts are made to provide D − recipients with D − PLTs to prevent anti‐ D alloimmunization and the potential for hemolytic disease of the fetus and newborn. B eth I srael D eaconess M edical C enter has a policy that when necessary to transfuse D + PLTs to D − patients, we recommend that RhIG be given when the patient is a woman of child‐bearing age or a potential liver transplant patient. We sought to retrospectively determine the rate of anti‐ D formation after D ‐incompatible apheresis PLT transfusions in those patients not receiving RhIG and not receiving D + RBCs over a 14‐year period at our institution. Study Design and Methods All D − patients (626) who received D + prestorage leukoreduced apheresis PLTs between J anuary 1, 1997, and D ecember 31, 2011, were identified. Those patients who received RhIG (45), D + RBC transfusions (50), or stem cell transplantation from a D + donor (16); had prior anti‐ D (23); or had unresolved R h at admission (8) were not eligible for analysis. Only those patients who had an antibody screen performed at least 4 weeks after the incipient PLT transfusion were evaluated (130). Results Of 130 eligible D − patients, 48% women and 57% immunocompetent, who received a total of 565 apheresis PLTs , none formed anti‐ D . Conclusion These findings support the use of D + apheresis PLTs without RhIG irrespective of D status in all recipients.