Infected Superior Mesenteric Artery Aneurysm following Streptococcus gallolyticus Bacteremia Associated with Cecal Cancer: A Case Report

Streptococcus gallolyticus bacteremia is associated with colorectal malignancy and infective endocarditis, whereas infected superior mesenteric artery aneurysm (SMAA) is rare. A 94-year-old woman with cecal cancer developed S. gallolyticus sepsis that improved with intravenous antibiotics. Two months later, contrast-enhanced computed tomography revealed a newly developed 17-mm distal SMAA, suggesting an infected aneurysm secondary to the prior bacteremia. Because of the high risk of rupture, urgent aneurysmectomy and ileocecal resection were performed. This rare case highlights an infected SMAA as a potential vascular complication of S. gallolyticus bacteremia, particularly in patients with underlying colorectal malignancy.