Repeat Ultrasound in Pediatric EDs Improves Appendicitis Diagnosis After Referral Imaging

Vitaliy Perepelista¹Jeffrey Ames¹Rahul Kaila¹Nicholas Sausen¹Kari Schneider¹Scott Lunos¹Bradley Segura¹Pablo Avendano¹Jeffrey P Louie^1,2*

• ¹M Health Fairview Masonic Children's Hospital, Minneapolis, United States
• ²University of Minnesota Twin Cities, Minneapolis, United States

ABSTRACT Background: Acute appendicitis is a leading cause of surgical emergencies in children, with ultrasound (US) emerging as a preferred diagnostic tool due to its lack of radiation and cost-effectiveness. However, the accuracy of US is highly operator-dependent and may vary between general referring emergency departments (EDs) and specialized pediatric EDs. Objective: To compare the diagnostic sensitivity and specificity of US performed at referring EDs versus a pediatric ED in identifying acute appendicitis. Methods: A retrospective study analyzed pediatric patients aged <18 years who underwent US at referring EDs and were transferred to a pediatric ED for repeat imaging between July 2018 and July 2023. Data collected included US findings, surgical pathology, white blood cell count, and patient disposition. Sensitivities of the US were calculated and compared between settings. Results: Among 64 children included, the US at the pediatric ED demonstrated higher sensitivity (85.2%) compared to referring EDs (51.9%) (p = 0.018). Pediatric ED US resulted in fewer nonvisualized appendices (a 34.4% reduction) and equivocal findings (a 30.5% reduction). Patients with positive surgical pathology exhibited higher white blood cell counts (mean 17.1) and neutrophil percentages (mean 81.0%). False positive rates were low (6.9%), aligning with published benchmarks. Conclusion: US performed at pediatric EDs exhibited superior diagnostic accuracy for appendicitis compared to referring EDs, likely due to operator expertise and enhanced imaging