Background: There are no clinical or laboratory tests that can eliminate the possibility of appendicitis in a child with abdominal pain that suggests the diagnosis. The standard of care is to admit these children to the hospital for observation. More than twice as many children hospitalized for abdominal pain suggesting appendicitis are subsequently sent home after observation compared to those who undergo appendectomy.
Objective: To evaluate the ability of CT with rectal contrast medium (CTRC) to diagnose a normal appendix in children with abdominal pain.
Materials and methods: A prospective cohort study in an urban pediatric emergency department. Children 6-17 years of age with abdominal pain were eligible when the attending physician planned to admit them for observation for possible appendicitis. All 94 patients underwent CTRC. CTRC results were compared to patient outcomes.
Results: Ninety-four children successfully underwent CTRC. Among the 53 patients with reflux of contrast medium into the ileum, the appendix was visualized in 43 (81.1%). Among all 94 cases, the appendix was visualized in 53 cases (55.7%); 43 studies were read as normal, and 10 showed appendicitis. Of the 43 with a normal appendix, 23 were discharged home, 18 were admitted but discharged uneventfully, and two underwent surgery for another diagnosis. When the appendix was visualized, the sensitivity, specificity, and negative and positive predictive values of CTRC were 100% (95% CI 66.4, 100.0), 97.7% (95% CI 88.0, 99.9), 100% (95% CI 91.8, 100.0), and 90% (95% CI 55.5, 99.8), respectively. The use of CTRC could have decreased the admission rate for observation for appendicitis by at least 41.8% and by more than 80% when the appendix could be seen.
Conclusion: Our data suggest that when the appendix can be visualized, CTRC can accurately identify a normal appendix and reduce the number of children hospitalized for observation for possible appendicitis.