Diffuse pulmonary lesions caused by ANCA-associated vasculitis: A case report

This case underscores the diagnostic challenges of AAV, especially when respiratory symptoms and CT findings resemble an infection. In patients with unexplained respiratory symptoms and diffuse lung changes unresponsive to antibiotics, AAV should be part of the differential. Early anti-neutrophil cytoplasmic antibody testing and multidisciplinary collaboration are crucial for timely diagnosis and treatment.