title: An analysis of discrepancies in HLA phenotypes of cadaver donors in the united network for organ sharing registry.
abstract: BACKGROUND
  HLA matching is an important component of the United Network for Organ Sharing algorithm for kidney allocation and is the primary factor in the mandatory sharing of kidneys that have zero HLA antigens mismatched with specific patients on the waiting list. An assessment of the HLA-A, -B, and -DR antigen discrepancy rate in the Organ Procurement and Transplantation Network database is desirable to judge the adequacy of the HLA typing data upon which the allocation program is based.
  
  
  METHODS
  A subset of the Organ Procurement and Transplantation Network database, composed of 10,047 cadaver donor HLA phenotypes that have been repeated by laboratories affiliated with organ recipient centers, was analyzed for the overall rate of HLA phenotype discrepancy and for the type and frequency of discrepancies of the individual HLA antigen assignments. The United Network for Organ Sharing HLA antigen equivalences were applied to the data.
  
  
  RESULTS
  Fourteen percent of 12,419 HLA typing comparisons were discrepant in at least one HLA antigen of six possible antigens per phenotype. Of a possible 74,514 individual HLA antigen assignments, 2.7% were discrepant. For African-American donors, the discrepancy rate was 5.1% as compared with 2.4% for Caucasian donors. The most frequent type of discrepancy was the assignment of an antigen blank versus a named antigen.
  
  
  CONCLUSIONS
  The discrepancy rate is comparatively low and can be expected to improve as more laboratories adopt methods for HLA typing by DNA typing techniques. It is recommended that the HLA data be further reviewed by the laboratories for possible typographical errors and that centers review the UNOS listing of HLA antigen equivalences and encourage laboratories to split HLA antigens.
authors.affiliation: Department of Surgery, University of California School of Medicine, San Francisco 94143, USA.
authors.forename: B W
authors.initials: BW
authors.lastname: Colombe
authors.forename: C D
authors.initials: CD
authors.lastname: Lou
mesh_terms: D002102:Cadaver; D006680:HLA Antigens / Q000032:analysis*; D006648:Histocompatibility; D006801:Humans; D016130:Immunophenotyping; D012042:Registries; D014015:Tissue Banks; D014019:Tissue Donors; D014481:United States
chemical_list: D006680:HLA Antigens