The Presence of Pretransplant Antiphospholipid Antibodies IgA Anti-b-2-Glycoprotein I as a Predictor of Graft Thrombosis After Renal Transplantation

Abstract

Background. Vessel thrombosis is a severe complication after renal transplantation. Antibodies anti-β-2 glycoprotein-I of IgA isotype (IgA-aB2GP1) have been linked to thrombotic events and mortality in hemodialysis patients. Methods. All kidney transplanted patients from 2000 to 2011 (n = 1375) in our hospital were followed up for 2 years, evaluating 3 time periods. Results. At transplantation, 401 patients were positive for IgA-aB2GPI (29.2%, group 1), and the remaining patients were negative (group 2). Graft loss at 6 months posttransplantation was higher in group 1 (18% vs 7.2%; P < 0.001). The most frequent cause of early graft loss was vessel thrombosis, especially in group 1 (12.2% vs 2.6% of patients; P < 0.001). In fact, vessel thrombosis was the most important cause of graft loss in the 3 time periods, irrespective of demographic changes and introduction of transplantation with asystolic donors. Notably, IgA-aB2GP1 was an independent risk factor for graft thrombosis (odds ratio, 5.047; P < 0.001). Furthermore, the presence of IgA-aB2GP1 was associated with early graft loss and delayed graft function. Mortality at 24 months was also higher in group 1. Conclusions. In conclusion, pretransplant IgA-aB2GP1 was the main risk factor for graft thrombosis and early graft loss. Further research should be made on whether anticoagulation in antibody-positive patients could ameliorate this catastrophic complication