Medical Image of the Week: Fibrosing Mediastinitis

Figure 1. Panel A: Thoracic CT showing airway occlusion (arrowhead) from fibrosing mediastinitis. Panel B: pulmonary artery obstruction (arrow) from fibrosing mediastinitis.

Histoplasmosis is endemic to the Midwest US and commonly causes an acute infection that presents as a subacute pneumonia. Chronic sequelae of histoplasmosis range from asymptomatic nodules to debilitating fibrosing mediastinitis (1). Mediastinal fibrosis represents exuberant scarring in response to histoplasmosis infection. Fibrosis may occlude airways (Figure 1A, arrow head) obstruct pulmonary arteries (figure 1B, arrow) or veins and impinge upon the esophagus and other vital structures residing in the mediastinum. Chest imaging shows subcarinal or mediastinal widening. CT scans may reveal fibrotic encasing of mediastinal structures and calcification of regional lymph nodes. Recurrent and often serious hemoptysis results from lung or airway damage and vascular compromise. Respiratory failure can occur. Treatment rarely includes stenting of airways or surgery (2). Vascular stenting may be indicated in some cases. Regardless, these difficult cases must be referred to centers with experience in histoplasmosis related complications.

¹Kenneth S. Knox, MD and ²Veronica A. Arteaga, MD

¹University of Arizona College of Medicine- Phoenix

²University of Arizona College of Medicine- Tucson

References

1. Peikert T, Colby TV, Midthun DE, Pairolero PC, Edell ES, Schroeder DR, Specks U.Fibrosing mediastinitis: clinical presentation, therapeutic outcomes, and adaptive immune response. Medicine (Baltimore). 2011 Nov;90(6):412-23. [CrossRef] [PubMed]
2. Hammoud ZT, Rose AS, Hage CA, Knox KS, Rieger K, Kesler KA. Surgical management of pulmonary and mediastinal sequelae of histoplasmosis: a challenging spectrum. Ann Thorac Surg. 2009 Aug;88(2):399-403. [CrossRef] [PubMed] 

Cite as: Knox KS, Arteaga VA. Medical image of the week: fibrosing mediastinitis. Southwest J Pulm Crit Care. 2017;14(2):85. doi: https://doi.org/10.13175/swjpcc015-17 PDF