Hepatitis B Virus-associated Vasculitis: A Case Report of Multiple Cavitary Masses in the Lung Mimicking Granulomatous Polyangiitis

: Hepatitis B virus (HBV) is one of the main causes of polyarteritis nodosa (PAN). We herein report a rare case of HBV-associated vasculitis presenting with multiple pulmonary nodules, mimicking granulomatous polyangiitis (GPA), with no abnormalities of the ear, nose, or kidney. A surgical lung biopsy revealed geographic necrosis surrounded by palisading granuloma and capillaritis. Because the HBV surface antigen was positive with a serum HBV-DNA level of 2.9 log10 copies/mL, we first treated the patient with entecavir and 2 weeks of prednisone 50 mg/day. The pulmonary nodules resolved, and seroconversion was observed after one month.