Staphylococcal mediastinitis due to sternoclavicular pyarthrosis: CT appearance.

Three cases of acute mediastinitis secondary to staphylococcal sternoclavicular pyarthrosis are reported. In each case, the patient presented with minimal signs and symptoms and mediastinitis was not suspected until demonstrated by preoperative CT. Since septic arthritis of the sternoclavicular joint may be insidious in onset and is associated with a high incidence of life-threatening secondary mediastinitis, CT is recommended as the initial imaging study in the evaluation of unexplained sternoclavicular joint pain and swelling.