纤维性纵隔炎(以下简称 FM)是一种原因不明的罕见疾病,其特征为进展缓慢的纵隔内纤维性变,且有大量胶原形成。临床表现多种多样,系由于纵隔组织特别是上腔静脉、肺动脉、肺静脉和支气管被挤压所致。通常 X 线表现为非对称性纵隔加宽;肺实质呈网状结节样间质浸润。本文报告两例 FM 年青患者,胸片显示:肺门扩大,局限性肺浸润。肺活检有肺实质浸润、显示近来肺梗塞;而纵隔活检具有 FM 的特征。 Fibrous mediastinitis (FM) is a rare disease of unknown origin characterized by slow progressive mediastinal fibrosis and massive collagen formation. A variety of clinical manifestations, due to the mediastinal tissue especially the superior vena cava, pulmonary artery, pulmonary vein and bronchus were squeezed. Usually X-ray showed asymmetric mediastinal widening; pulmonary parenchyma was mesocytic nodular interstitial infiltration. This article reports two cases of FM young patients, chest X-ray showed: hilar enlargement, limited pulmonary infiltration. Pulmonary biopsy has pulmonary parenchymal infiltration, which shows recent pulmonary infarction; and mediastinal biopsy has the characteristics of FM.