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
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- 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]