Comparison of PAS and Alvarado score in diagnosis of Pediatric acute appendicitis

Abstract

Introduction: Acute abdomen is the leading of admission of pediatric patients to the Emergency and Surgical departments and its most common cause is acute appendicitis. Diagnostic mistakes for acute appendicitis occur 28-57% of 2-12 years old patients, almost 100% in patients under 2 years old.The are several different scoring systems being used internationally for diagnosis of acute appendicitis, to prevent from delayed diagnosis and further complications.7-9 Objectives: The purpose of this study was to compare the diagnostic sensitivity of Pediatric Appendicitis Score (PAS) and Alvarado scoring systems for acute appendicitis diagnosis in pediatric patients. Methods: We prospectively evaluated children of 3 to 17 years old with acute appendicitis who were admitted to the department of surgery at NCMCH, in the period from September to December 2019. Both scores were rated in each patient and Threshold values were determined by ROC curve analysis. Results: The study involved 107 pediatric patients, 89 (83.17%) confirmed appendicitis with pathological study. Alvarado score average in patients with and without acute appendicitis was 6.7 and 4.2, respectively. (P<0.001). The PAS average score was 7.1 for patients with acute appendicitis and 4.8 for patients without acute appendicitis (P<0.001). Based on the ROC curve analysis, the best cutoff point was 6 for both PAS and Alvarado score. With the cutoff point ≥6 by Alvarado score, 70 patients were confirmed with acute appendicitis and its sensitivity was 78.6%, specificity 77.7%, positive predictive value 94.5%. With the cutoff point ≥6 by PAS, 77 patients were confirmed with acute appendicitis and its sensitivity was 86.5%, specificity 77.7%, positive predictive value 95%. We found no significant differences between both scores. Conclusions: In comparison with pathological study, both Alvarado and PAS score has same cutoff point of 6. With the cutoff point ≥6 by Alvarado score, 70 patients were confirmed with acute appendicitis and its sensitivity was 78.6%, specificity 77.7%, positive predictive value 94.5%. With the cutoff point ≥6 by PAS, 77 patients were confirmed with acute appendicitis and its sensitivity was 86.5%, specificity 77.7%, positive predictive value 95%. No significant differences between both scores.