Von – Willebrand Factor, a Possible Biomarker for Disease Activity in Vasculitis

Abstract

Abstract Background: Inflammation markers commonly used to evaluate disease activity in vasculitis, C- reactive protein (CRP) and sedimentation rate, are often normal despite active disease. Von – Willebrand factor (vWF), is synthesized primarily in endothelial cells and secreted in response to vascular damage. Sporadic reports suggested increased vWF levels in vasculitis.Aim: To evaluate vWF serum concentration in patients with vasculitis as a marker of disease activity.Methods: Adult patients with systemic vasculitis were prospectively enrolled. Disease activity was recorded using the Birmingham Vasculitis Activity Score (BVAS) v3. Blood group adjusted vWF antigen serum level was evaluated at diagnosis and when available after treatment.Results: Twenty-five patients with systemic vasculitis were compared to 15 healthy controls. The mean age of patients was 56 ± 17 years and 56% were women. 40% had ANCA-associated vasculitis; 20% had giant cell arteritis; 16% had polyarteritis nodosa; 8% had Takayasu arteritis and the rest had other vasculitides. The mean disease duration was 3.4 ± 4.8 years. Mean vWF was higher in patients with active vasculitis compared to patients in remission or low disease activity state and healthy controls- 212%±81, 159%±80, and 106%±26, respectively. vWF levels directly correlated with BVAS. In 13 patients with active vasculitis who reached remission or LDA after treatment, vWF level at follow-up decreased significantly. In 3/5 patients who were treated with IL-6 inhibitors, vWF was elevated despite normal CRP levels, while clinically vasculitis was active.Conclusion: vWF Ag serum level is increased in active vasculitis and is suggested as a biomarker for disease activity.