Study of anti-endothelial cell antibodies in SLE patients with acute ischemic stroke.

Endothelial dysfunction is the predominant manifestation of SLE. Anti-endothelial cell antibodies (AECA) are a heterogeneous group of autoantibodies directed against different antigens in endothelial cells. The objective of this study was to assess the possible correlation between the presence of AECA and ischemic stroke manifestations in SLE. The AECA titers in serum from 34 patients with SLE and acute ischemic stroke (8 men and 26 women, mean age 38.37 +/- 3.25 years) and in 32 controls (11 men and 21 women, mean age 37.52 +/- 3.86 years) were tested. The method used was ELISA. The data were expressed as mean +/- SD from indicated number of patients. Comparison between patients and controls was expressed as relative risk with its 95% confidence interval (RR[95% CI]), where lower limit > 1.0 was considered significant. All p values were determined by Fisher's exact test. A value of p < 0.05 was considered statistically significant. AECA were positive in 31 out of 34 patients, mean value 19.2 +/- 16.3 U/mL and in 8 out of 32 controls, mean value 5.5 +/- 2.6 U/mL (RR 7.154 [95% CI 2.801 to 18.274]), p < 0.0001. Patients with SLE and acute ischemic stroke tended to have higher mean values of AECA. AECA play a pivotal role in the pathogenesis of neurologic complications of SLE. AECA titers in SLE patients with acute ischemic stroke support a role for AECA as potential diagnostic marker possibly associated to cerebral manifestations of SLE patients. Further study is needed in order to clarify if AECA presence is related to systemic diseases severity and to situate their importance among other markers of endothelial dysfunction.