2026 Volume 68 Issue 5 Pages 1068-1073
An 86-year-old woman presented to our hospital with fever and lower abdominal pain. Non-contrast abdominal CT revealed a 28 mm pelvic abscess and multiple diverticula in the adjacent sigmoid colon. Initially, the abscess was presumed secondary to sigmoid diverticular penetration. Conservative treatment, including fasting and intravenous antibiotics, was initiated; however, no significant clinical improvement was observed. On treatment day 7, repeat contrast-enhanced CT revealed abscess enlargement and a fish bone was identified as the causative agent. Considering the elapsed time since onset, the perforation site was presumed to have adhered to the surrounding abscess cavity. In consultation with the gastrointestinal surgery team, the fish bone was endoscopically removed. Subsequently, abscess drainage into the intestinal lumen occurred, resulting in rapid resolution of inflammation.
