title: ABO antibody titer and risk of antibody-mediated rejection in ABO-incompatible renal transplantation.
abstract: Therapeutic plasma exchange (TPE) preconditioning with immunosuppressive therapy reduces ABO antibody titers, permitting engraftment of ABO-incompatible (ABO-I) kidney transplants. The posttransplant predictive role of ABO antibody titers for antibody-mediated rejection (AMR) is unknown. This retrospective study evaluated 46 individuals who received TPE to permit ABO-I kidney transplantation. ABO antibody titers were performed using donor-type indicator red cells. Seven individuals (15.2%) experienced clinical or subclinical AMR. There was no significant difference between recipient blood group, number of pretransplant TPE and baseline titer between those with and without AMR. At 1-2 weeks posttransplant the median titer was 64 (range 4 - 512) among individuals with AMR and 16 (range 2 - 256) among individuals without AMR. Total agglutination reactivity score was significantly higher among individuals with AMR (p = 0.046). The risk of AMR was significantly higher among individuals with an elevated posttransplant titer of >or=64 (p = 0.006). The sensitivity of an elevated posttransplant titer was 57.1% with a specificity of 79.5%. The positive predictive value was 33.3% and the negative predictive value was 91.2%. Most individuals with AMR have an elevated titer, however, the positive predictive value of a high titer for AMR is poor.
authors.affiliation: Department of Pathology, Johns Hopkins Medical Institutions, Baltimore, MD, USA.
authors.forename: A A R
authors.initials: AA
authors.lastname: Tobian
authors.forename: R S
authors.initials: RS
authors.lastname: Shirey
authors.forename: R A
authors.initials: RA
authors.lastname: Montgomery
authors.forename: W
authors.initials: W
authors.lastname: Cai
authors.forename: M
authors.initials: M
authors.lastname: Haas
authors.forename: P M
authors.initials: PM
authors.lastname: Ness
authors.forename: K E
authors.initials: KE
authors.lastname: King
mesh_terms: D000328:Adult; D000906:Antibodies / Q000276:immunology; D000971:Antineoplastic Combined Chemotherapy Protocols; D001761:Bleomycin; D001788:Blood Grouping and Crossmatching; D005260:Female; D006801:Humans; D007136:Immunoglobulins / Q000276:immunology; D016030:Kidney Transplantation / Q000276:immunology*; D008297:Male; D008727:Methotrexate; D008875:Middle Aged; D010951:Plasma Exchange / Q000379:methods*; D010956:Plasmapheresis; D012189:Retrospective Studies; D012307:Risk Factors; D014019:Tissue Donors; D014750:Vincristine
chemical_list: D000906:Antibodies; D007136:Immunoglobulins; D001761:Bleomycin; D014750:Vincristine; D008727:Methotrexate