[Bloody sputum with cavitary lesions on chest computed tomography scans: a case report].

This article reported a case of a middle-aged man with a 1-year history of intermittent cough and production of bloody sputum. Serum autoantibodies of the patient were negative. Early in the course of the disease, chest computed tomography (CT) scans showed a nodule in the right middle lung lobe with cavity formation. Surgical resection of the lesion was done with a postoperative pathological diagnosis of inflammatory pseudotumor. No treatment was given and his symptoms recurred with new patches in the right upper lobe. Pathology consultation from another hospital found vasculitis under the microscope and a diagnosis of granulomatosis with polyangiitis was made. His symptoms still worsened after glucocorticoid therapy. Final pathological consultation from Peking Union Medical College Hospital reached a diagnosis of pulmonary actinomycosis. Pulmonary lesions were absorbed after anti-infection treatment. The diagnosis and treatment of this patient provided more data for understanding of the relationship between infection and vasculitis among clinicians and pathologists.