Mycotic aneurysm of the descending thoracic aorta caused by Haemophilus influenzae.

A 59-year-old man presented with a three-month history of back pain, and enhanced computed tomography demonstrated an acutely expanding aneurysm of the descending thoracic aorta with slight erosion of the corresponding vertebrae. Because of suspected infectious or inflammatory etiology, he was managed with a combination of emergency aortic repair using prosthetic graft with omental flap and antibiotic chemotherapy. Haemophilus influenzae was identified from perioperative specimens and the postoperative course was uneventful.