Descending mediastinitis: a review.

CONTEXT: Mediastinitis is an inflammation of connective tissue that involves mediastinal structures. When the condition has an infectious origin located in the cervical or oral region, it is termed "descending mediastinitis" (DM).

DATA SOURCES: The subject was examined in the light of the authors' own experiences and by reviewing the literature available on the subject. The Medline, Lilacs and Cochrane databases were searched for articles, without time limits, screening for the term "descending mediastinitis". The languages used were English and Spanish.

DATA SYNTHESIS: There are three main fascial pathways by which oral or cervical infections can reach the mediastinum: pretracheal, lateropharyngeal and retropharyngeal. About 70% of DM cases occur via the retropharyngeal pathway. The mortality rate is about 50%. According to infection extent, as seen using computed tomography, DM can be classified as focal (type I) or diffuse (type II). The clinical manifestations are nonspecific and resemble other systemic infections or septic conditions. The primary treatment for DM consists of antibiotics and surgical drainage. There are several approaches to treating DM; the choice of approach depends on the DM type and the surgeon's experience. In spite of all the improvements in knowledge of the microbiology and physiopathology of the disease, controversies still exist regarding the ideal duration of antibiotic therapy and whether tracheostomy is really a necessary procedure.

CONCLUSION: Since DM is a lethal condition if not promptly treated, it must always be considered to represent an emergency situation.