Hepatitis B Virus-Related Polyarteritis Nodosa Presenting With Multiple Lung Nodules and Cavitary Lesions

The patient presented here is a 59-year-old Japanese man with active chronic hepatitis B with precore and core promoter mutated virus, presenting with high fever, bloody sputum, and multiple lung nodules with excavation. Surgical biopsy of the lung nodule showed necrotizing vasculitis affecting pulmonary arteries without granulomatous changes. The pulmonary manifestations of this patient resembled Wegener granulomatosis. However, the pathologic findings showing nongranulomatous necrotizing vasculitis involving the small pulmonary arteries, presence of circulating immune complex, absence of antineutrophil cytoplasmic antibodies, and excellent response to the combination therapy of corticosteroid and an anti-hepatitis B virus agent, entecavir, led us to the diagnosis of hepatitis B virus-related polyarteritis nodosa (PAN). Radiographic evidence of lung nodules or cavitations seen in systemic vasculitis patients has been considered a sign suggestive of granulomatous disease and a diagnostic surrogate marker for necrotizing granulomatous vasculitis, but a clinical relevance to hepatitis B virus-related PAN has not been reported before this case.