They might be caused by a constricted airway, constricted esophagus, or constricted blood vessels. Symptoms also depend on how mush fibrosis has occurred. There may be cough, shortness of breath, coughing up blood, pain in the chest, and difficulty in swallowing. Causes
Acute
Esophageal perforation, a form of direct contamination, accounts for 90% of acute mediastinal infections. Esophageal perforation can arise from vomiting, incidental trauma from a procedure or operation, external trauma, ingestion of corrosive substances, malignancy, or other esophageal disease.Other causes of acute mediastinitis include infection secondary to cervical disease which arises from dental procedures, skin infections of the neck, neck trauma, or neck procedures.Descending necrotizing mediastinitis (DNM) was first described by Herman E. Pearse Jr., M.D. in 1938 and he stated, "the term mediastinitis means little unless qualified by a description of its type and kind." Although Descending Necrotizing Mediastinitis is an acute mediastinitis, it is distinct because it does not originate from structures within the mediastinum. Therefore, the term Descending Necrotizing Mediastinitis implies that the infection of the mediastinum originated from a primary site in the head or neck and descended through fascial spaces into the mediastinum.Though rare in developed countries, acute mediastinitis can be caused by inhalation of bacterial spores such as Anthrax. Historically, this infection was referred to as Wool-sorters Disease. In the lungs, spores can spread via lymphatics to mediastinal lymph nodes, where the mature rods can release exotoxins promoting edema and tissue necrosis. Clinically, persons infected with anthrax can develop a hemorrhagic mediastinitis, which manifests as acute pulmonary hemorrhage and meningitis.
Chronic
Most cases of granulomatous mediastinitis (75%) are incidentally found on chest x-rays which show a mediastinal mass, or widening of the mediastinum. Treatment
Treatment for acute mediastinitis usually involves aggressive intravenous antibiotic therapy and hydration. If discrete fluid collections or grossly infected tissue have formed (such as abscesses), they may have to be surgically drained or debrided.Treatment for DNM usually requires an operation to remove and drain infected necrotic tissue. Broad spectrum intravenous antibiotics are also given to treat the infection. Patients are typically managed in the intensive care unit due to the severity of the disease.Treatment for chronic fibrosing mediastinitis is somewhat controversial, and may include steroids or surgical decompression of affected vessels. Prognosis
Fibrosing mediastinitis can lead to entrapment of mediastinal structures. The mortality of DNM ranges from 10 to 40% due to sepsis and multi-organ failure if not recognized and intervened upon early. References
External links

Mediastinitis at the US National Library of Medicine Medical Subject Headings (MeSH)