Von Willebrand factor antigen as a marker of disease activity in childhood-onset antineutrophil cytoplasmic antibody-associated vasculitis

Ellen Go; Florence A Aeschlimann; Hua Lu; Jenna R Larry; Diane Hebert; Rae S M Yeung; Damien Noone

doi:10.1093/rheumatology/kead600

Von Willebrand factor antigen as a marker of disease activity in childhood-onset antineutrophil cytoplasmic antibody-associated vasculitis

Rheumatology (Oxford). 2023 Nov 14:kead600. doi: 10.1093/rheumatology/kead600. Online ahead of print.

Authors

Ellen Go^{1

2}, Florence A Aeschlimann^{1

3}, Hua Lu¹, Jenna R Larry⁴, Diane Hebert⁵, Rae S M Yeung¹, Damien Noone⁵

Affiliations

¹ Division of Rheumatology, Department of Paediatrics, The Hospital for Sick Children, University of Toronto, Toronto, Ontario, Canada.
² Division of Rheumatology, Department of Paediatrics, Riley Hospital for Children, Indiana University, Indianapolis, Indiana, USA.
³ Paediatric Rheumatology, University of Basel Children's Hospital, Basel, Switzerland.
⁴ School of Medicine and Medical Science, University College Dublin, Belfield, Dublin, Ireland.
⁵ Division of Nephrology, Department of Paediatrics, The Hospital for Sick Children, University of Toronto, Toronto, Ontario, Canada.

PMID: 37963037
DOI: 10.1093/rheumatology/kead600

Abstract

Objective: Von Willebrand Factor (VWF) antigen plays a role in vascular inflammation and thrombosis, both important in the pathogenesis of Antineutrophil Cytoplasmic Antibody-associated vasculitis (AAV). Previous work found that VWF correlates with disease activity in childhood-onset primary CNS vasculitis. We sought to determine the relationship between VWF and disease activity over time in children with AAV.

Methods: AAV patients with more than one VWF level measured were included in this retrospective stuy, and the relationship between active vasculitis, VWF and other disease measures were analyzed. Generalized estimating equations (GEE) analysis was used to account for repeated VWF measurements within a patient. Repeated measures correlation was used to determine associations of paired laboratory observations. Diagnostic performance was evaluated using receiver operating curve (ROC) analysis.

Results: 732 total VWF measurements were collected in 33 AAV patients. VWF antigen levels were higher during active disease (median = 2.03 IU/ml, IQR = [1.35, 2.55]) compared with inactive disease (median = 1.18 IU/ml, IQR = [0.94, 1.53). VWF antigen was the only variable that was significantly associated with active disease (OR 3.01, p< 0.001, 95CI [2.3, 3.93]). The effect of VWF did not show a substantial difference between the disease subtypes. There was a moderate positive correlation between VWF antigen and disease activity, with an acceptable sensitivity and specificity rates.

Conclusion: Increased VWF antigen levels correlate with active vasculitis in this paediatric-onset AAV cohort and may be used as an additional biomarker in childhood AAV.

Keywords: Anti-neutrophil cytoplasmic antibody; Wegener’s granulomatosis; biomarkers; microscopic polyangiitis; paediatric rheumatology; vasculitis.