An 84-year-old man underwent endovascular stent graft placement 5 years ago for a thoracoabdominal aneurysm. He presented now with vague abdominal pain, tachypnea, fever, and hypoxia. Contrast abdominopelvic and chest computed tomography showed the thoracoabdominal endograft in proper position; the excluded aneurysmal sac demonstrated increased enhancement and enlargement compared with prior examinations, measuring 3.8 cm. No contrast extravasated into the sac. Blood cultures grew Bacteroides fragilis.