Computed tomography in complicated acute appendicitis.

Due to the position and length of the appendix, intraabdominal abscesses after perforation in complicated acute appendicitis may occur in several different and sometimes unsuspected anatomical locations. Five patients are described with proven complicated acute appendicitis and inflammatory processes in multiple sites: anterior pararenal space, general retroperitoneum, subcutaneous fat space, intraperitoneal cavity, and small bowel mesentery. A confusing case of ileocecal carcinoid with mesenteric involvement is also presented. In all cases complicated acute appendicitis was diagnosed on CT prior to surgery, except in 1 case in which a pelvic abscess developed after intramural cecal bleeding in a patient with hemophilia B.