Diagnostic Accuracy of Inflammatory Biomarkers in Differentiating Acute Appendicitis From Other Acute Abdomen and Predicting Disease Severity: A Prospective Comparative Cross‐Sectional Study

Abstract

ABSTRACT Introduction Acute appendicitis (AA) is one of the most common clinical conditions for emergency surgery. The diagnosis of acute appendicitis remains challenging for surgeons. Researchers are still looking for a parameter that is less expensive and easily available for diagnosis. The main aim of the study was to determine the diagnostic accuracy of inflammatory biomarkers for AA and the severity of inflammation. Methods A prospective comparative cross‐sectional study was conducted among 161 participants (80 with acute appendicitis and 81 non‐AA abdominal pain controls) recruited using a consecutive sampling technique. The study was conducted from August 21, 2024 to January 16, 2025. In this study, we have investigated the diagnostic utility of white blood cells (WBC), neutrophil to lymphocyte ratio (NLR), systemic inflammatory index (SII) and systemic inflammation response index (SIRI) for AA. Normality was assessed using the Shapiro–Wilk test and visual inspections. Mean differences for WBC were compared using the Independent sample t ‐test, while the Mann–Whitney U test was employed for others. ROC curve analysis was done for statistically significant parameters ( p value < 0.05 with 95%CI). Post‐hoc power analysis was performed using G*Power 3.1.9.7 to ensure study robustness. Result Males account for 57.76% of participants. The mean age of non‐AA and AA group was 26.47 ± 8.53 and 24.34 ± 9.77 years, respectively. The AA group demonstrated significantly higher WBC, NLR, SII and SIRI levels compared to non‐AA. Significantly higher WBC, NLR, SII and SIRI levels were observed in complicated AA (CAA) groups relative to simple AA (SAA) groups. The area under the ROC curve (AUC) of WBC, NLR, SII, and SIRI to diagnose AA was 0.814, 0.834, 0.816, and 0.814, respectively. WBC, NLR, SII, and SIRI can predict CAA with AUC of 0.722, 0.781, 0.770, and 0.715, respectively. Conclusion Inflammatory markers, including WBC, NLR, SII, and SIRI have acceptable diagnostic performance for AA. Additionally, WBC, NLR, SII and SIRI possess potential for differentiating CAA from SAA. It may be better for surgeons to consider the level of NLR, SII and SIRI for the diagnosis of AA and to determine its severity. However, further studies on a larger sample size are recommended to validate their clinical utility.