Higher antineutrophil cytoplasmic antibody (C-ANCA) titers are associated with increased overall healthcare use in patients with sinonasal manifestations of granulomatosis with polyangiitis (GPA).

Background: Granulomatosis with polyangiitis (GPA) is an autoimmune disease characterized by necrotizing granulomatous airway inflammation and vasculitis. Sinonasal involvement occurs in more than 80% cases, with antineutrophil cytoplasmic antibody (C-ANCA) titers used as a marker of disease severity. The purpose of this study was to determine whether C-ANCA levels impact radiographic findings and healthcare use in patients with sinonasal GPA.