Fibrosing mediastinitis is a condition that affects the area between the lungs (mediastinum) which contains the heart, large blood vessels, windpipe (trachea), esophagus, and lymph nodes. People with fibrosing mediastinitis have varying amounts of scar tissue in the mediastinum which may cause problems for the organs located there. For example, some affected people may develop blocked airways that can interfere with lung function. Others may have compressed blood vessels which can slow or prevent blood flow to and from the heart. The exact cause of fibrosing mediastinitis is not fully understood, but it is not inherited. Many cases are linked to a specific type of fungal infection called histoplasmosis. Treatment depends on which structures of the mediastinum are affected, the severity of the scarring and, in some cases, the cause of the condition.

Histoplasma capsulatum usually have no symptoms or only a mild, flu-like illness. However, fibrosing mediastinitis appears to be a late and rare complication in less than 1% of histoplasmosis cases.

Other less common causes of fibrosing mediastinitis include radiation therapy, autoimmune disease, tuberculosis, certain medications, Behcet's disease, and inflammatory diseases such as sarcoidosis. In roughly 10-20% of cases, the cause of fibrosing mediastinitis cannot be determined.

Most cases have been linked to a specific type of fungal infection called histoplasmosis. Other less common causes of fibrosing mediastinitis include radiation therapy, autoimmune disease, tuberculosis, certain medications, Behcet's disease, and inflammatory diseases such as sarcoidosis.

There is no cure for fibrosing mediastinitis and the benefits of current treatments are unclear. In general, treatment options depend on which structures of the mediastinum are affected (i.e. the heart, large blood vessels, windpipe, esophagus, and lymph nodes), the severity of the scarring and, in some cases, the cause of the condition. For example, fibrosing mediastinitis caused by histoplasmosis may be treated with antifungal medications while cases caused by autoimmune disorders may respond best to corticosteroids. Other treatment options include surgery to removed scarred tissue and local therapies to treat specific problems (i.e. stents, laser therapy).