Diagnosis and management of acute diverticulitis.

Uncomplicated diverticulitis is localized diverticular inflammation, whereas complicated diverticulitis is diverticular inflammation associated with an abscess, phlegmon, fistula, obstruction, bleeding, or perforation. Patients with acute diverticulitis may present with left lower quadrant pain, tenderness, abdominal distention, and fever. Other symptoms may include anorexia, constipation, nausea, diarrhea, and dysuria.