Diverticulitis

Diverticulitis is inflammation in a colonic diverticulum, usually in the sigmoid colon. Diverticula form when colonic mucosa and submucosa herniate through weak points in the muscular wall. If a pouch becomes obstructed, retained contents promote bacterial stasis and focal ischemia; the process may remain contained or progress to micro-perforation, abscess, fistula, or peritonitis. That distinction drives triage. Uncomplicated disease has localized inflammation without perforation or abscess. Complicated disease includes perforation, an abscess at least 4 cm, fistula, or peritonitis. The same presenting complaint—abdominal pain with fever—can therefore lead to outpatient symptom control or urgent hospital and surgical management.