To investigate the clinical differentiating features between antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) and relapsing polychondritis (RP) with laryngeal involvement. 

A retrospective analysis and comparison were conducted on the clinical manifestations, airway imaging findings, and involvement of organs in 7 patients with AAV and 42 patients with RP who had laryngeal involvement.

Serologically, 6 out of the 7 AAV patients were ANCA-positive, whereas all RP patients were ANCA-negative. In terms of imaging, laryngeal masses and vocal cord paralysis were characteristic findings in AAV, whereas extensive airway involvement was more common in RP. Furthermore, AAV was frequently associated with sinusitis, otitis media and orbital mass, whereas auricular chondritis was a characteristic feature in RP patients.

ANCA testing serves as an important diagnostic differentiator. RP typically involves a more extensive and severe airway compromise, while AAV is often accompanied by extra-airway organ involvement. This study summarized the clinical characteristics, imaging features, and patterns of organ involvement in AAV and RP patients with laryngeal lesions, aiming to facilitate accurate differential diagnosis and individualized management.