Clinical and computed tomography findings of appendiceal diverticulitis vs acute appendicitis.

Aim: To study the clinical features and computed tomography (CT) findings of appendiceal diverticulitis vs acute appendicitis.

Methods: We retrospectively reviewed the records of 451 patients who had undergone appendectomy in our institution from January 2007 to September 2012. Patient demographics, clinical features, pathological findings, and surgical outcomes were analyzed. We also compared preoperative CT images of 25 patients with appendiceal diverticulitis with those of 25 patients with acute appendicitis.

Results: Among 451 patients, 44 (9.7%) were diagnosed to have appendiceal diverticulitis and 398 (86.9%) to have acute appendicitis. Patients with appendiceal diverticulitis were older (59 vs 37 years, P < 0.001) and had a longer duration of the illness (4.0 d vs 1.0 d, P < 0.001). Perforation rates in patients with appendiceal diverticulitis were higher (68% vs 27%, P < 0.001). The appendix could be visualized in only 13 patients (52%) among the appendiceal diverticulitis cases, but in all acute appendicitis cases. CT findings suggestive of appendiceal diverticulitis included the absence of fluid collection in the appendix (84% vs 12%, P < 0.001), absence of appendicolith (92% vs 52%, P = 0.005), and formation of abscess (68% vs 16%, P < 0.001). Appendiceal diverticula were identified in 6 patients (24%).

Conclusion: Among patients who had undergone appendectomy, 9.7% had appendiceal diverticulitis. Patients with appendiceal diverticulitis had different clinical features and CT findings from patients with acute appendicitis.