Appendicitis inflammatory response versus pediatric appendicitis score for grading disease severity in children.

Acute appendicitis is a frequent surgical emergency in children, and early recognition of severe forms remains challenging. This prospective observational study compared the Appendicitis Inflammatory Response (AIR) and Pediatric Appendicitis Score (PAS) for grading disease severity in pediatric acute appendicitis. Among 542 children assessed, 138 with suspected appendicitis were included, and 136 underwent appendectomy. All included patients were prospectively scored with AIR and PAS, and clinical, radiologic, intraoperative, and histopathologic findings were recorded. Associations between score categories and complicated appendicitis (gangrenous, abscess, or diffuse peritonitis) or perforated appendicitis were analyzed, and diagnostic performance was assessed using receiver operating characteristic curves. Higher AIR and PAS categories were associated with increasing appendix diameter; AIR categories were significantly associated with both complicated appendicitis and perforation, whereas PAS categories were significantly associated only with perforation. For complicated appendicitis, the area under the curve (AUC) was slightly higher for AIR than PAS, whereas for perforation both scores showed similar AUCs. These findings suggest that AIR is more informative than PAS for overall grading of disease severity in pediatric acute appendicitis, while AIR and PAS provide comparable, moderate accuracy for predicting perforation.