Evaluation of the usefulness of the appendicitis risk calculator in the pediatric population with abdominal pain A six year single-center observational study

Abstract

Introduction: Acute appendicitis is a frequent cause of acute abdomen; in pediatrics, the diagnosis is mainly clinical, but it can present in an atypical way. The probability of a diagnosis of appendicitis can be measured with the Pediatric Appendicitis Risk Calculator (pARC) and the Alvarado Index. This study aimed to evaluate the diagnostic capacity of these scales in pediatric patients with abdominal pain assessed at a reference center.

Methods: The present cross-sectional study was carried out with patients from 5 to 19 years of age with acute abdominal pain treated at the Hospital de Los Valles, Quito-Ecuador, between January 2015 and December 2020. pARC and the Alvarado index were applied. A descriptive analysis and diagnostic tests are performed. ROC, PPV, NPV, concordance, correlation between both scales, specificity, and sensitivity were calculated.

Results: There were 284 cases. The prevalence of appendicitis was 8.9% (95% CI 7.27-10.79), and the Alvarado scale and the pARC calculator presented ROC values of 0.919 (95% CI = 0.885-0.953) and 0.926 (95% CI = 0.896-0.955), respectively. The cutoff point for sensitivity and specificity was 4 for the Alvarado Index and 12 for pARC. The Alvarado Index was 82.11 (95% CI 72.9-89.2) and 88.36 (95% CI 82.9-92.6), and for pARC, it was 83.16 (95% CI 74.1-90) and 86.77 (95% CI 81.1- 91.2). The PPV and NPV in the Alvarado Index were 78.00 (95% CI 68.6-85.7) and 90.76 (95% CI 85.6-94.5), pARC 75.96 (95% CI 66.5-83.8) and 91.11 (95% CI 85.9-94.8), respectively.

Conclusions: The ability to predict the diagnosis of acute appendicitis was the same between the pARC calculator and the Alvarado Index; both are valuable and reliable tools.