Efficacy of Modified Alvarado Score versus Tzanakis Score in Diagnosing Acute Appendicitis: A Prospective Observational Study

Introduction: Acute appendicitis is one of the most prevalent surgical emergencies worldwide, with complications arising from delayed diagnosis or misdiagnosis. Accurate and timely diagnosis is critical to prevent complications like perforation, abscess, and peritonitis, while minimising unnecessary surgeries. Aim: To study the diagnostic accuracy of Tzanakis Scoring (TS) versus the Alvarado scoring system, considering histopathology as a gold standard. Materials and Methods: A prospective observational study was conducted at the Outpatient Department (OPD) of Surgery and Emergency Room (ER), S Nijalingappa Medical College (SNMC), HSK (Hanagal Shree Kumareshwar) Hospital and Research Centre, Bagalkot, Karnataka, India from August 2022 to February 2024. A total of 100 patients who presented with right lower quadrant pain were included. Both the Modified Alvarado Score (MAS) and TSs were calculated for each patient. The diagnostic performance of each scoring system was evaluated against histopathological findings. The sensitivity, specificity, Positive Predictive Value (PPV), Negative Predictive Value (NPV), and diagnostic accuracy were calculated for both the MAS and TS. Receiver Operating Characteristic (ROC) curves were constructed to determine the optimal cut-off values for each scoring system. Results: The mean age was 29.3±11.8years, and out of 100 patients, 54 were males. A total of 75 had histologically confirmed appendicitis. The TS demonstrated higher sensitivity (92.0% vs 88.0%), specificity (80.0% vs 76.0%), and diagnostic accuracy (89.0% vs 85.0%) compared to MAS. The Area Under the ROC Curve (AUC) was 0.895 for the TS and 0.860 for MAS (p-value<0.001 for both). Cut-off values were ≥8 for the TS and ≥7 for MAS. Both scoring systems reduced negative appendectomy rates compared to clinical judgment alone (4.1% for TS, 5.6% for MAS, vs 8.5% for clinical judgment). Conclusion: Both the MAS and TS are effective tools for diagnosing acute appendicitis, with the TS showing slightly superior performance. These scoring systems can aid in clinical decision-making and potentially reduce negative appendectomy rates. Further large-scale studies are warranted to validate these findings across diverse populations.