A 76-year-old woman presented to the emergency department with a fever (38.9°C), vomiting, and diarrhea of 2 days’ duration. The patient's medical history included coronary artery disease, stroke, hypertrophic cardiomyopathy, diastolic heart failure, hypertension, and end-stage renal disease, for which she received dialysis. She had no personal or family history of colon cancer. Blood cultures demonstrated growth of Streptococcus gallolyticus (formerly known as Streptococcus bovis) group bacteremia. A transesophageal echocardiogram did not show valvular vegetation. Colonoscopy results revealed a nonobstructing, fungating mass in the distal rectum (image A). Histologic evaluation confirmed low-grade rectal adenocarcinoma with submucosal invasion (image B). The patient was treated with 2 g of intravenous ceftriaxone daily, as the minimal inhibitory concentration to penicillin was 0.10 μg/mL. This regimen was changed to 2 g of cefazolin 3 times per week after dialysis when she was discharged to an acute rehabilitation center for a total of 4 weeks of therapy. She underwent transanal excision of her colonic mass and did not require further radiation or chemotherapy. 

Patients with S gallolyticus bacteremia or endocarditis have a higher rate of colorectal cancer compared with the general population.¹ Specifically, there is a higher risk for advanced adenomas and invasive carcinomas, and colonoscopy may be necessary.²