[ANCA-negative granulomatosis with polyangiitis: a case report].

We reported a case of 73-year-old male with multiple pulmonary nodules and cavities. The patient was admitted with a chief complaint of "dry cough with shortness of breath for 3 months". Chest CT showed multiple irregular masses, nodules, and patchy lesions in both lungs, accompanied by the formation of cavities. He also had anemia and renal dysfunction. Despite given empirical anti-infective and anti-tuberculosis treatments, the pulmonary nodules progressed, and the cavities enlarged. Anti-neutrophil cytoplasmic antibodies (ANCA) were negative twice. Bronchoscopic biopsy was performed. The mucosal pathology of the right middle lobe lesion showed little necrosis, focal granulomatous structure formation, and relevant vasculitis and remaining vessel wall structure in the necrosis lesions by elastic fiber staining. A clinical diagnosis of ANCA-negative necrotizing granulomatous polyangiitis was made and the patient was treated with glucocorticoids and cyclophosphamide. The nodules and cavities shrank, and some lesions were absorbed.