Antiendothelial cell antibodies in patients with Wegener's granulomatosis: Prevalence and correlation with disease activity and manifestations

Objective. Previous studies in small cohorts of patients with Wegener's granulomatosis (WG) or anti-neutrophil cytoplasmic antibody (ANCA) associated vasculitis have yielded conflicting data regarding the prevalence of antiendothelial cell antibodies (AECA), ranging from 8% to 100%, and the use of AECA as a measure of disease activity. We examined a large, well-characterized cohort of patients with WG and active disease for the presence of AECA. Methods. Serum from subjects with WG who participated in a clinical therapeutic trial was collected at baseline, when all subjects had active disease. Clinical manifestations and disease activity were documented using the Birmingham Vasculitis Activity Score for WG (BVAS/WG). Serum AECA (IgG) was measured by cyto-ELISA using unfixed human umbilical vein endothelial cells (HUVEC). The AECA positivity cutoff was determined using 71 healthy control samples. Statistical analyses utilized Student's t test, chi-square and Fisher's exact tests, and linear regression. Results. AECA were detected in 34 of 173 (20%) evaluated serum samples. Mean BVAS/WG did not differ between patients with (7.3 ± 3.2) or without AECA (7.0 ± 3.3) (p = 0.58). Among the 34 patients positive for AECA, the antibody titer did not correlate with disease activity (BVAS/WG; r = 0.09, p = 0.60). There were no statistically significant differences in the frequency of major clinical manifestations between patients with or without AECA. Conclusion. AECA, as measured using HUVEC, are not highly prevalent among patients with active WG, are not associated with specific clinical manifestations, and do not correlate with level of disease activity.