Secondary signs may improve the diagnostic accuracy of equivocal ultrasounds for suspected appendicitis in children

• Authors: Kristin N. Partain, Emory University; Adarsh Patel, Emory University; Curtis Travers, Emory University; Courtney McCracken, Emory University; Jonathan Loewen, Emory University; Kiery Braithwaite, Emory University; Kurt Heiss, Emory University; Mehul Raval, Emory University
• Journal Title: Journal of Pediatric Surgery
• Volume: Volume 51, Number 10
• Publisher: Elsevier | 2016-10-01, Pages 1655-1660
• Type of Work: Article | Post-print: After Peer Review
• Publisher DOI: http://doi.org/10.1016/j.jpedsurg.2016.03.005
• Subjects: Health Sciences, Radiology; Health Sciences, Medicine and Surgery
• Keywords: Science & Technology; Life Sciences & Biomedicine; Pediatrics; Surgery; Pediatric surgery; Appendicitis; Secondary signs; Ultrasound; Quality improvement; COMPUTED-TOMOGRAPHY; PEDIATRIC APPENDICITIS; IMAGING MODALITY; PREDICTIVE-VALUE; US EXAMINATION; CT; MANAGEMENT; HOSPITALS; OUTCOMES; IMPACT

Abstract

Introduction: Ultrasound (US) is the preferred imaging modality for evaluating appendicitis. Our purpose was to determine if including secondary signs (SS) improve diagnostic accuracy in equivocal US studies. Methods: Retrospective review identified 825 children presenting with concern for appendicitis and with a right lower quadrant (RLQ) US. Regression models identified which SS were associated with appendicitis. Test characteristics were demonstrated. Results: 530 patients (64%) had equivocal US reports. Of 114 (22%) patients with equivocal US undergoing CT, those with SS were more likely to have appendicitis (48.6% vs 14.6%, p  <  0.001). Of 172 (32%) patients with equivocal US admitted for observation, those with SS were more likely to have appendicitis (61.0% vs 33.6%, p  <  0.001). SS associated with appendicitis included fluid collection (adjusted odds ratio (OR) 13.3, 95% confidence interval (CI) 2.1–82.8), hyperemia (OR = 2.0, 95%CI 1.5–95.5), free fluid (OR = 9.8, 95%CI 3.8–25.4), and appendicolith (OR = 7.9, 95%CI 1.7–37.2). Wall thickness, bowel peristalsis, and echogenic fat were not associated with appendicitis. Equivocal US that included hyperemia, a fluid collection, or an appendicolith had 96% specificity and 88% accuracy. Conclusion: Use of SS in RLQ US assists in the diagnostic accuracy of appendicitis. SS may guide cl inicians and reduce unnecessary CT and admissions.