Comparative Analysis of Appendicitis Inflammatory Response Score Versus ALVARADO Score as a Diagnostic Tool for Acute Appendicitis

Background: Acute appendicitis remains one of the most common surgical emergencies, yet its diagnosis poses significant clinical challenges due to overlapping symptoms with other abdominal pathologies. Imaging techniques, while helpful, are not always accessible in resource-limited settings, highlighting the need for reliable, cost-effective clinical scoring systems. Although the Alvarado score has been widely used, its diagnostic accuracy is limited by subjective parameters. The Appendicitis Inflammatory Response (AIR) score, a newer tool incorporating objective biochemical markers, may offer improved diagnostic precision, but comparative evidence remains limited in local clinical settings. Objective: To compare the diagnostic accuracy of the Appendicitis Inflammatory Response (AIR) score with the Alvarado score in predicting acute appendicitis using histopathological findings as the gold standard. Methods: This prospective cohort observational study was conducted at the General Surgery Department of Combined Military Hospital (CMH) Rawalpindi from July 1 to December 31, 2022. A total of 185 patients with clinical suspicion of acute appendicitis who underwent surgery were included. Both Alvarado and AIR scores were calculated preoperatively, but surgical decisions were made independently by the on-call consultant based on clinical assessment. Histopathological confirmation was obtained for all cases. Data were collected using structured proformas and analyzed using SPSS v27. Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and diagnostic accuracy were calculated. Ethical approval was obtained from the institutional review board, and the study adhered to the Declaration of Helsinki. Results: Of the 185 patients (mean age 28.21 years), 108 (58.4%) were male. Surgical approaches included open appendectomy (31.4%), laparoscopic (64.9%), and laparoscopic converted to open (3.8%). Histopathology confirmed acute appendicitis in 162 (87.6%) cases. The AIR score demonstrated superior diagnostic performance with an accuracy of 89.19%, sensitivity of 90.12%, specificity of 82.61%, PPV of 97.33%, and NPV of 54.29%. In contrast, the Alvarado score had a lower accuracy of 69.73%, sensitivity of 70.37%, specificity of 65.22%, PPV of 93.44%, and NPV of 23.81%. Conclusion: The AIR score significantly outperformed the Alvarado score in diagnosing acute appendicitis, offering a more accurate and objective clinical tool, particularly valuable in settings where access to imaging is limited. Its integration into diagnostic protocols may enhance clinical decision-making and reduce unnecessary surgeries.