Isolation of Listeria monocytogenes from a Patient with Sealed Ruptured Thoracoabdominal Aortic Aneurysm

Abstract

We are reporting a case of sealed rupture of thoracoabdominal aortic aneurysm associated with the isolation of Listeria monocytogenes. The patient was a 75-year-old man with previous history of hypertension that had not required medication for the 3 years prior to hospital admission. He was admitted due to chest pain, but he was afebrile. There were no clinical findings indicating infection, although CRP was slightly elevated. During his clinical course, a sealed rupture of a thoracoabdominal aortic aneurysm was found and replaced with an artificial artery. After surgery, he was treated for 2 weeks with sultamicillin. He was discharged from hospital on the 43rd postoperative day. No bacteria were observed after microscopic examination of gram stained samples from the thrombus that was present in the sealed rupture of the aneurysm. However, a L. monocytogenes strain isolated from the thrombus only after enrichment culturing by HK medium at 37°C for 4 days. By histopathology, there was a slight cellular infiltration of lymphocytes and neutrophils at the aperture of the aneurysm. Although L. monocytogenes strains possess major pathogenic genes, such as prfA, hlyA, plcA, plcB, mpl, inlA, inlB and actA that can be identified by PCR, none of the evidence indicated that this case was a mycotic aortic aneurysm due to L. monocytogenes.