Does Ultrasounding Children Referred for Appendicitis Aid the Choice to Operate?

Purpose: To determine whether the use of ultrasound (USS) assists in the diagnosis of appendicitis in paediatric patients. Method: A retrospective study of patients <14 years, referred to paediatric surgery with possible appendicitis from Jul 2015 to Nov 2016. Groups were based on the decision to admit with or without USS and their Alvarado scores (AS). Diagnosis was confirmed by histopathology. Outcomes were missed appendicitis, negative appendicectomy rate (NAR), and specificity of diagnosis. Results: 234 patients were included. 126 (54%) underwent appendicectomy and 102 (44%) had appendicitis. USS was performed in 163 patients (70%) and was 83% sensitive and 87% specific. Clinical diagnosis had greater specificity with USS 88% (CI 95%, 80-93) than without USS 59% (39-78). There was no significant difference in the NAR with USS (18%) and without (20%). All 29 patients AS 9-10 had appendicitis of these 15 (52%) had USS prior to theatre. None of the 30 patients AS 0-3 had appendicitis. In the group of 98 patients AS 6-8, those 59 who had an USS had a NAR of 2.86% and specificity of 96% (80-100), compared to NAR of 20% and specificity of 36% (11-69) in the 39 patients without. Conclusion: USS aids diagnostic accuracy through increasing the specificity, it does not benefit in AS ≥9 and ≤3 where the diagnosis is clinically evident. Consideration should be made to reduce these USS to lessen referral delay, hospital expense and misleading clinical decision-making. USS appears most useful in patients AS 6-8, with improved outcomes identified.