Racial differences in the availability of human leukocyte antigen- matched platelets

In view of the demonstrated difficulty of providing African American patients with compatible red cells and bone marrow from the predominantly white donor population in the United States, it should be determined if African American patients have greater difficulty obtaining human leukocyte antigen (HLA)-matched platelets. Twenty-two alloimmunized African American patients and 20 alloimmunized white patients were studied. These groups were HLA-matched against our hospital pheresis service (1,157 donors), the local Red Cross pool (3,405 donors), and the combined population (4,562 donors). The frequency of each patient's HLA phenotype was calculated in the white population and in the African American population. More African Americans did not have a well matched (A or BU) platelet donor. Fewer African American patients had sufficient matched (A and B) donors to support the average period of aplasia. On average, the African American patients had half as many matched donors as compared to the White patients. Sixty-eight percent of African American patients had HLA types which were more difficult to find in a white population. Ninety percent of white patients had HLA phenotypes which were more common in the white population. We have shown that it is more difficult to obtain HLA-matched platelets for alloimmunized African American patients as compared to alloimmunized white patients. With larger donor pools, platelet support for African American patients is easier, but uncommon HLA types remain. Our results support efforts to enlarge the donor pool with an emphasis on specific recruitment programs aimed at the African American community.