[A case of pulmonary-limited Wegener granulomatosis mimicking bacterial pneumonia caused by Staphylococcus aureus].

A 56-year-old woman who had suffered from systemic lupus erythematosus and Sjögren syndrome was admitted complaining of persistent cough. Chest X-ray films showed an infiltrative shadow in the right middle lung field. Her serum PR3-ANCA titer was high, and granulomatous inflammation with Langhans giant cell was noted in a transbronchial biopsy specimen. About 3 months later, purulent sputum and high grade fever developed, with a new infiltrative shadow in the left upper lung field noted on a chest X-ray film. We treated her based on a diagnosis of bacterial pneumonia caused by methicillin-resistant Staphylococcus aureus, but her condition did not improve. We finally gave her a diagnosis of pulmonary-limited Wegener's granulomatosis. Her condition improved with the administration of sulfamethoxazole-trimethoprim, prednisolone and cyclophosphamide. We report a case of pulmonary-limited Wegener granulomatosis which mimicked bacterial pneumonia caused by methicillin-resistant Staphylococcus aureus. This case suggests that Wegener's granulomatosis should be considered on encountering pneumonia caused by Staphylococcus aureus.