Archived case 199 · March 4-March 11, 2016
42 year old male, non-smoker, previous farmer, presented with 2-3 year history of exertional dyspnea. A CT scan of the chest was obtained.
What are the imaging findings and how do you explain them? What is the appropriate differential diagnosis?
PA and lateral radiographs show mild rightward mediastinal shift, mild volume loss of the right lung and right pleural thickening and/or effusion. There is enlargement of the right hilum with calcifications. A calcified nodule is noted in the right lower lobe. CT axial image in soft tissue and lung window redemonstrates mild rightward mediastinal shift due to mild volume loss and atelectasis in the right mid and lower lobes. There is fibrocalcific adenopathy of the right hilum with complete occlusion of the right pulmonary artery and the right superior pulmonary vein and effacement of the right hilar bronchial structures. Compensatory hypertrophy of some of the bronchial arteries is noted. There is parietal pleural thickening along the costal and diaphragmatic pleura with trace pleural effusion. There are extensive subpleural reticulation and areas of linear and round atelectasis. There is a large calcified granuloma in the right lung base. Answer Diagnosis: Fibrosing Mediastinitis
Fibrosing Mediastinitis
Fibrosing mediastinitis is a rare benign disease characterized by proliferation of dense fibrous tissue within the mediastinum. It mainly affects young patients from endemic areas. The patients present with signs and symptoms related to obstruction of vital mediastinal structures. Most cases of Fibrosing Medistinitis are caused by an idiosyncratic fibroinflammatory reaction to previous H capsulatum infection.
Differential diagnosis in this case (obstructive hilar mass. For the first three DD if the mass is not calcified):
Carcinoma
Lymphoma
Tuberculosis
Other fungal infections
Reference:
Fibrosing Mediastinitis
Santiago E. Rossi , H. Page McAdams , Melissa L. Rosado-de-Christenson , Teri J. Franks , Jeffrey R. Galvin
RadioGraphics , May 2001, Vol. 21: 737–757, 10.1148/radiographics.21.3.g01ma17737Original case written by its authors at Virginia Commonwealth University and published at this address as part of a weekly teaching collection. Reproduced here as an archive.