Not All Roads Lead to the Cecum: A Rare Case of Colonic Duplication in an Adult

A 73-year-old man presented with bright red blood per rectum 5 days after transrectal ultrasound (TRUS) and prostate biopsy for prostate cancer. On presentation, his blood pressure was stable at 130/89 mm Hg, and his heart rate was 110 beats/min. Rectal examination revealed blood clots. His hemoglobin was 10.4 g/dL (baseline 14 g/dL). Urgent flexible sigmoidoscopy showed active oozing at the low anterior wall of the rectum, which matched with the location of the prostate biopsy site. Two metallic clips were placed at the oozing site for hemostasis. Due to a significant amount of blood in the sigmoid colon, other proximal causes of bleeding couldn’t be ruled out. A follow-up colonoscopy 6 weeks later revealed severe sigmoid colon diverticular disease. At 20 cm from the anal verge, the colon appeared to diverge into 2 separate lumens (Figure 1). One lumen was blind and extended for 25 cm, and the other lumen led to the cecum (Video 1). Diverticular disease was also noted in the blind duplicated lumen. Barium enema showed a potential branching point of the sigmoid colon, but the anatomy was difficult to evaluate due to severe diverticular disease (Figure 2). Four years prior to this presentation, the patient underwent a colonoscopy, but the duplication was not reported