An algorithm to locate hr^B– donors for individuals with sickle cell disease

Many African Americans with sickle cell disease (SCD) develop alloantibodies to antigens in the Rh blood group system.Others have shown that from D– individuals, those lacking the high-incidence hr^Bantigen (> 98% prevalence) may be found among r’r African Americans. We describe an algorithm to locate units for African Americans with SCD and anti-hr^B and -D. From 46,539 donations, 5136 listed African American as race. Our primary reference laboratory performed Rh phenotyping (D, C, c, E, e) for first-time donors and those not tested previously. Specimens typing r’r were sent to a secondary reference laboratory for hr^Bphenotyping after each donation.Hemoglobin S screening was performed.Of 24 donors (27 donations) who phenotyped r’r, seven donors,29.2 percent (nine donations) were hr^B–.Two of seven who donated twice consistently tested hr^B–. One of 24 donors initially tested hr^B–, but hr^B+ on repeat donation. The donor tested hr^B– by a second reference laboratory. Reagents for phenotyping high-incidence antigens are often not readily available, requiring a specialized reference laboratory that adds cost and turnaround time. Our algorithm selected r’r African American donors most likely to lack hr^B for further evaluation by a second reference laboratory.We felt this was the most judicious use of resources and provided the greatest opportunity to find compatible components for individuals with SCD and anti-hr^B and -D. Immunohematology 2002;18:82–84.