Circulating anti-endothelial cell antibodies are associated with poor outcome in renal allograft recipients with acute rejection.

BACKGROUND AND OBJECTIVES Anti-endothelial cell antibody (AECA) can cause hyperacute rejection and immediate graft loss after renal transplantation; however, its prevalence and significance during acute rejection are unknown. Previous studies suggested that AECA may be detected in recipients with acute vascular rejection (AVR). DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS We retrospectively analyzed 653 cadaveric renal transplant recipients; circulating AECA was positive in 13 of 47 cases of AVR; another two cases of hyperacute rejection also had detectable AECA. Twenty-six cases of AVR without circulating AECA were selected as controls. RESULTS AECA-positive AVR usually occurred within 1 yr after transplantation and mostly was resistant to steroid treatment. Compared with the control group, the AECA-positive group was associated with a significantly lower 1-yr graft survival rate (46.7 versus 80.5%; P = 0.038), and more patients had histologic interstitial plasma cell infiltration (53.8 versus 11.5%; P = 0.005). More patients with AECA-positive AVR experienced another one or more episodes of acute rejection during 1 yr of follow-up (75.0 versus 13.0%; P = 0.003). AECA-positive AVR with C4d deposition in peri-tubular capillaries had the worst outcome in this cohort, and it accounted for 38.5% graft loss in AVR. AECA in turn accounted for 71.4% of graft loss in C4d(+) AVR. CONCLUSIONS Circulating AECA is associated with poor outcome in renal allograft recipients with acute rejection and should be monitored regularly.