Abstract
BACKGROUND: Pulmonary artery aneurysms are a rare but life-threatening manifestation of Behçet's disease and are associated with a high risk of fatal hemoptysis. Standard treatment typically involves high-dose corticosteroids combined with cyclophosphamide; however, concerns regarding long-term toxicity and fertility preservation have prompted interest in alternative immunosuppressive strategies. CASE DESCRIPTION: We report the case of a 20-year-old male who presented with recurrent hemoptysis and systemic inflammatory features and was diagnosed with Behçet's disease complicated by multiple pulmonary artery aneurysms. Computed tomography pulmonary angiography demonstrated several saccular aneurysms, the largest measuring 52 mm in the right lower-lobe pulmonary artery with partial mural thrombosis. The patient was treated with high-dose corticosteroids followed by oral prednisone in combination with mycophenolate mofetil. At four-week follow-up, inflammatory markers had normalized, and repeat imaging demonstrated regression of the aneurysm sizes without new vascular complications.The patient remained clinically stable and was scheduled for further imaging and rheumatology evaluation at two months. CONCLUSIONS: This case highlights mycophenolate mofetil as a potential steroid-sparing immunosuppressive option for pulmonary artery aneurysms in Behçet's disease.