[Thoracic aortic aneurysm in the setting of metastatic mediastinitis].

The aetiological spectrum of thoracic aortic aneurysms is extensive. Infectious aneurysms (formerly mycotic aneurysms) constitute only a small percentage of all thoracic aortic aneurysms, they are usually small and often develop as complications of bacterial endocarditis. We report the case of a 39-year-old insulin-dependent diabetic, who developed a leaking aneurysm of the thoracic aorta as a late complication of a knee empyema with subsequent metastatic mediastinitis. Clinical, radiological, biochemical and microbiological data are correlated with histopathological findings. The development of this unusual thoracic aortic aneurysm is shown from impending rupture to successful vascular graft implantation.