mediastinal fibrosis (fibrosing mediastinitis)

An exuberant fibrotic reaction in the mediastinum. Etiology: 1) histoplasmosis (most common cause in USA) 2) tuberculosis 3) autoimmune disease 4) pharmaceutical agents - methysergide 5) idiopathic Pathology: 1) delayed hypersensitivity reaction 2) most patients do not have active histoplasmosis at the time of diagnosis 3) histologic preparations may show non-viable histoplasma organisms 4) granuloma formation may be seen 5) calcification of hilar & mediastinal lymph nodes may be seen 6) calcified tissue may erode into the bronchial lumen causing broncholithiasis 7) fibrosis may encircle airways, esophagus & vessels causing compression & occlusion of these structures

General

fibrosis mediastinal disease (diseases of the mediastinum)

References

Mayo Internal Medicine Board Review, 1998-99, Prakash UBS (ed) Lippincott-Raven, Philadelphia, 1998, pg 775