Anti-elastase ANCA-associated vasculitis: a case report and literature review

Abstract Antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) is a systemic necrotizing vasculitis that primarily affects small- to medium-sized vessels and represents a spectrum of diseases with overlapping clinical and immunopathological features. While anti-proteinase 3 (anti-PR3) and anti-myeloperoxidase (anti-MPO) are the most common ANCA autoantibodies, other ANCA specificities, such as anti-elastase, have been described, but their clinical significance remains uncertain. We report the case of a 38-year-old male presenting with chronic rhinosinusitis, nasal crusting, and epistaxis. Imaging revealed a septal perforation, and histopathological analysis showed necrotizing vasculitis. ANCA serology was positive for perinuclear-ANCA (p-ANCA), with negative anti-PR3 and anti-MPO but positive anti-elastase antibodies. A diagnosis of incomplete AAV with a sinonasal granulomatosis with polyangiitis (GPA) phenotype was established. In order to understand the prevalence of anti-elastase antibodies in AAV, a narrative review was conducted. In six retrospective studies, prevalence varied between 0% and 16.7%, suggesting limited diagnostic utility of anti-elastase in AAV. This case highlights the relevance of histopathological confirmation in AAV, particularly in atypical ANCA profiles. Anti-elastase antibodies may have limited value as a biomarker in AAV, given their low prevalence. Immunosuppressive treatment was effective, reinforcing the importance of early recognition and intervention in AAV.