Mediastinum Anatomy Acute CT scan of a patient with Descending Necrotizing<unk> . 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<unk>  include infection secondary to cervical disease which arises from dental procedures, skin infections of the neck, neck trauma, or neck procedures. Descending necrotizing<unk>  (DNM) was first described by Herman E. Pearse Jr., M.D. in 1938 and he stated, "the term<unk> ' means little unless qualified by a description of its type and kind." Although Descending Necrotizing<unk>  is an acute<unk> , it is distinct because it does not originate from structures within the mediastinum. Therefore, the term Descending Necrotizing<unk>  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<unk>  can be caused by inhalation of bacterial spores such as Anthrax. Historically, this infection was referred to as Wool-sorter's 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<unk> , which manifests as acute pulmonary hemorrhage and meningitis. Hallmark finding of disease is a widened mediastinum visualized on chest x-ray. Once clinical symptoms of anthrax induced<unk>  appear, disease is nearly 100% fatal. Individuals with known exposure to spores may be treated prophylactically with antibiotics (fluoroquinolones or tetracycline) to prevent disease progression. Chronic There are two types of fibrosing<unk> : granulomatous and non-granulomatous. Granulomatous<unk>  is due to a granulomatous process of the mediastinal lymph nodes leading to fibrosis and chronic abscesses in the mediastinum. The most common causes are histoplasmosis and tuberculosis infections. Non-granulomatous fibrosing<unk>  is caused by an idiopathic reaction to drugs and radiation therapy. Autoimmune disease and Behcet's disease are also causes. Etiology An observational retrospective study of 17 patients diagnosed with DNM found that the infections most often originated from neck infections including tonsillar abscess, pharyngitis, and epiglottitis. The study also found that most infections are poly-microbial. Often the culprits are usually Gram-positive bacteria and anaerobes, though rarely, Gram-negative bacteria are also present. This severe form represents 20% of acute<unk>  cases.
Mediastinitis
Tonsillitis
Bronchitis
Tracheal tumor
Tracheitis
Lung abscess
Croup
Tracheobronchitis