title: Risk stratification by the virtual crossmatch: a prospective study in 233 renal transplantations.
abstract: The virtual crossmatch (virtual-XM) has been proposed for accurate identification of donor-specific HLA-antibodies, but large prospective studies assessing its value for pretransplant risk stratification are lacking. A total of 233 consecutive renal allograft recipients were prospectively stratified according to the virtual-XM. In patients with a negative virtual-XM (n=190, 82%), prospective cytotoxicity crossmatches (CDC-XM) were omitted, and they received standard immunosuppression. Virtual-XM positive patients were only transplanted if CDC-XM were negative. They received additional induction with anti-T-lymphocyte-globulin and intravenous immunoglobulins (n=43, 18%). The cumulative incidence of clinical/subclinical antibody-mediated rejection (AMR) at 1 year was lower in the negative virtual-XM than in the positive virtual-XM group [15/190 (8%) vs. 18/43 (42%); P<0.0001]. After a median follow-up of 2.6 years, allograft loss because of AMR occurred less often in the negative virtual-XM group (1% vs. 7%; P=0.04) and death-censored allograft survival at 2 years was higher (98% vs. 91%; P=0.02). Serum creatinine was not different at the last follow-up (129 μm vs. 130 μm; P=0.58). We conclude that a negative virtual-XM defines patients at low risk for AMR and early allograft loss, while a positive virtual-XM represents a significant risk for AMR despite enhanced induction therapy. This supports the utility of the virtual-XM for risk stratification and treatment allocation.
authors.affiliation: Transplantation Immunology and Nephrology, University Hospital Basel, Petersgraben 4, Basel, Switzerland.
authors.forename: Patrizia
authors.initials: P
authors.lastname: Amico
authors.forename: Patricia
authors.initials: P
authors.lastname: Hirt-Minkowski
authors.forename: Gideon
authors.initials: G
authors.lastname: Hönger
authors.forename: Lorenz
authors.initials: L
authors.lastname: Gürke
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Mihatsch
authors.forename: Jürg
authors.initials: J
authors.lastname: Steiger
authors.forename: Helmut
authors.initials: H
authors.lastname: Hopfer
authors.forename: Stefan
authors.initials: S
authors.lastname: Schaub
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D003601:Cytotoxicity Tests, Immunologic; D005260:Female; D006084:Graft Rejection / Q000453:epidemiology / Q000276:immunology*; D006680:HLA Antigens / Q000276:immunology; D006650:Histocompatibility Testing; D006801:Humans; D016030:Kidney Transplantation / Q000009:adverse effects / Q000276:immunology* / Q000401:mortality; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D018570:Risk Assessment; D014019:Tissue Donors; D014584:User-Computer Interface
chemical_list: D006680:HLA Antigens