Abdominal aortic pseudoaneurysm caused by prolonged methicillin-resistant Staphylococcus aureus sepsis.

The mechanism of pseudoaneurysm formation caused by prolonged sepsis is thought to be related to the vascular endothelium being directly invaded and broken by bacteria. Moreover, matrix metalloproteinases (MMPs) which are up-regulated by chronic inflammation have been reported to be implicated in the pathogenesis of aneurysm development through increased proteolysis of extracellular matrix proteins. An effective treatment for infected pseudoaneurysm remains unsettled. Surgery is generally performed, however, because the patients in most of these cases are in very poor physical condition, the operation is associated with high morbidity and mortality. A more successful alternative is endovascular treatment. Recent reports indicate low morbidity and mortality rates with this treatment. If the patient in this case had been in better condition, we could have selected endovascular stent-grafting for her treatment.