A Case of Remitting Seronegative Symmetrical Synovitis with Pitting Edema Syndrome Complicated with Organizing Pneumonia.

We herein report a 62-year-old man with idiopathic pulmonary fibrosis who developed remitting seronegative symmetrical synovitis with pitting edema (RS3PE) syndrome during follow-up. Pulmonary infiltrations were detected concomitantly with the development of RS3PE syndrome, and prednisolone improved both the pulmonary and extrapulmonary lesions. Recognizing the pulmonary manifestations of RS3PE syndrome is necessary to provide an appropriate diagnosis and disease management.