Colovesical fistula caused by an ingested chicken bone

Colovesical fistula involving the sigmoid colon is the most common fistulous communication between the gastrointestinal tract and the urinary bladder. These tracts are most commonly associated with diverticulitis but might arise secondary to a neoplasm, inflammatory bowel disease, iatrogenic injuries, radiation therapy, trauma, or foreign bodies. We describe a patient who developed a fistula between the sigmoid colon and bladder secondary to an ingested chicken bone that lodged in a colonic diverticulum. A portion of the foreign body was removed by direct visualization on colonoscopy; the remaining fragment passed spontaneously per urethra after hospital discharge.