title: Unintended Consequences of the New National Kidney Allocation Policy in the United States.
abstract: The new national Kidney Allocation System of the Organ Procurement and Transplantation Network (OPTN), effective as of December 4, 2014, was designed to improve the chances of transplanting the most highly sensitized patients on the waitlist, those with calculated panel reactive antibody values of 98%, 99% and 100%. Recently, it was suggested that these highly sensitized patients will experience inequitable access, given the reported high prevalence of antibodies to HLA-DP, and the fact that only about 1/3 of deceased donors are typed for HLA-DP antigens. Here we report that 320/2948 flow cytometric crossmatches performed for the Northwestern transplant program over the past 28 months were positive solely due to HLA-DP donor-specific antibodies (11%; 16.5% of patients with HLA antibodies-sensitized patients). We further show that 58/207 (12%) HLA-DR serologically matched donor-recipient pairs had a positive B cell flow crossmatch due to donor-specific HLA class II antibodies, and 2/34 (6%) serologic zero-HLA-A-B-DR mismatch had a positive flow crossmatch due to HLA-DSA. We therefore provide information regarding the necessity and importance of complete donor HLA typing including both chains of the HLA-DP antigen (encoded by HLA-DPA1 and HLA-DPB1) at the time of organ offer.
authors.affiliation: Comprehensive Transplant Center, Feinberg School of Medicine, Northwestern University, Chicago, IL.
authors.forename: A R
authors.initials: AR
authors.lastname: Tambur
authors.affiliation: Comprehensive Transplant Center, Feinberg School of Medicine, Northwestern University, Chicago, IL.
authors.forename: K M K
authors.initials: KM
authors.lastname: Haarberg
authors.affiliation: Comprehensive Transplant Center, Feinberg School of Medicine, Northwestern University, Chicago, IL.
authors.forename: J J
authors.initials: JJ
authors.lastname: Friedewald
authors.affiliation: Comprehensive Transplant Center, Feinberg School of Medicine, Northwestern University, Chicago, IL.
authors.forename: J R
authors.initials: JR
authors.lastname: Leventhal
authors.affiliation: Comprehensive Transplant Center, Feinberg School of Medicine, Northwestern University, Chicago, IL.
authors.forename: M F
authors.initials: MF
authors.lastname: Cusick
authors.affiliation: Gift of Hope Organ & Tissue Donor Network, Itasca, IL.
authors.forename: A
authors.initials: A
authors.lastname: Jaramillo
authors.affiliation: Comprehensive Transplant Center, Feinberg School of Medicine, Northwestern University, Chicago, IL.
authors.forename: M M
authors.initials: MM
authors.lastname: Abecassis
authors.affiliation: Center for Transplantation, University of Kansas Medical Center, Kansas City, KS.
authors.forename: B
authors.initials: B
authors.lastname: Kaplan
mesh_terms: D005434:Flow Cytometry; D059867:HLA-DP alpha-Chains / Q000276:immunology*; D059868:HLA-DP beta-Chains / Q000276:immunology*; D006648:Histocompatibility / Q000276:immunology; D006650:Histocompatibility Testing; D006801:Humans; D006967:Hypersensitivity / Q000276:immunology*; D007518:Isoantibodies / Q000276:immunology; D016377:Organ Transplantation; D040841:Resource Allocation / Q000331:legislation & jurisprudence* / Q000592:standards*; D014019:Tissue Donors; D009927:Tissue and Organ Procurement / Q000458:organization & administration*; D014481:United States
chemical_list: D059867:HLA-DP alpha-Chains; D059868:HLA-DP beta-Chains; C071172:HLA-DPA1 antigen; C071170:HLA-DPB1 antigen; D007518:Isoantibodies
keywords: Organ Procurement and Transplantation Network (OPTN); ethics and public policy; kidney transplantation/nephrology; organ allocation; organ procurement and allocation