Clostridium septicum Triad Infected Aortic Aneurysm, Empyema, and Colon CancerOnuorah, Luke N. MBBS, MPH; Czachor, John S. MDInfectious Diseases in Clinical Practice: September 2019 - Volume 27 - Issue 5 - p 288–289 doi: 10.1097/IPC.0000000000000750 Case Reports Buy Abstract Author InformationAuthors Article MetricsMetrics Infected aortic aneurysm is a rare occurrence accounting for 2.6% of described aneurysms. Staphylococcus species and Salmonella species are the most frequently isolated microbes, with Clostridium septicum being decidedly less commonly detected. It is well documented that C. septicum bacteremia in the presence of an infected aneurysm is strongly associated with gastrointestinal cancer, particularly colorectal adenocarcinoma. Although blood cultures were repeatedly negative, a left pleural effusion culture grew C. septicum. The patient was treated with an endovascular prosthesis and prolonged antibiotic therapy including lifelong suppression. Serial abdominal computed tomographic scans with contrast displayed an enlarging appendiceal lesion that was described as a mucocele. Surgical histopathology revealed an invasive moderately differentiated adenocarcinoma. This case highlights both the association of C. septicum with malignancy and the utility of pleural effusion culture in the presence of culture-negative infected aortic aneurysm. From the Wright State University Boonshoft School of Medicine, Miami Valley Hospital, Dayton, OH. Correspondence to: John S. Czachor, MD, 128 East Apple St, 2nd Floor, Weber Building, Dayton, OH 45409. E-mail: firstname.lastname@example.org. L.N.O. has no conflicts of interest. J.S.C. has received honoraria and is on the speakers bureau for Allergan. Online date: June 3, 2019 Copyright © 2019 Wolters Kluwer Health, Inc. All rights reserved.