Does Right Lower Quadrant Abdominal Ultrasound Accurately Identify Perforation in Pediatric Acute Appendicitis?

BACKGROUND: Acute appendicitis is the most common cause of acute abdomen in pediatric emergency department (ED) visits, and right lower quadrant abdominal ultrasound (RLQUS) is a valuable diagnostic tool in the clinical approach. The utility of ultrasound in predicting perforation has not been well-defined. OBJECTIVES: We sought to determine the sensitivity of RLQUS to identify perforation in pediatric patients with appendicitis. METHODS: A chart review of all patients 3 to 21 years of age who received a radiographic work-up and who were ultimately diagnosed with perforated appendicitis between 2010 and 2013 at a pediatric ED was conducted. The final read for ultrasonography was compared to either the operative diagnosis, surgical pathology diagnosis, or further imaging results (if the patient was managed nonoperatively). Test characteristics were calculated for the identification of appendicitis and identification of perforation. RESULTS: Of the 539 patients evaluated for appendicitis, 144 (26.7%) patients had appendicitis, and 40 of these (27.8%) were perforated. Thirty-nine had RLQUS performed as part of their evaluation. Of these, 28 had positive findings for appendicitis, and 9 were read as definite or possible perforated appendicitis. The sensitivity of RLQUS for the diagnosis of appendicitis in the group with perforation was 77.1% (95% confidence interval [CI], 59.4-89%) and the sensitivity for diagnosing a perforation was 23.1% (95% CI, 11.1-39.3%). CONCLUSION: There was a low rate of detection of perforation by RLQUS in our pediatric population. If larger studies confirm this, additional imaging should be recommended in patients with a high suspicion of perforation and in whom a diagnosis of perforation would change management.