The Diagnostic Accuracy of Hyperbilirubinemia in Predicting Appendicitis and Appendiceal Perforation

Background Every diagnostic tool that may assist in the identification of appendicitis is of great importance to emergency general surgeons. While recent research has indicated that hyperbilirubinemia can serve as a valuable predictor of appendiceal perforation, these studies have not specifically examined the role of bilirubin as an indicator for acute appendicitis. This study aimed to assess the role of hyperbilirubinemia as a diagnostic factor in detecting appendicitis and appendiceal perforation. Methodology This single-center retrospective study involved 333 patients with acute appendicitis who underwent an emergency appendectomy at a model three hospital between January 2021 and December 2022. Statistical analysis was performed using STATA/SE 18.0 for Windows (StataCorp., College Station, TX, USA) to compare bilirubin levels, white blood cell count (WCC), and C-reactive protein (CRP) among normal appendices, non-perforated appendicitis, and perforated appendicitis. Results Among 333 patients, 60.66% were male, and 39.34% were female, with a male-to-female ratio of 1.54:1. The average hospital stay was 3.27 ± 3.02 days. Hyperbilirubinemia was observed in 25.53% (85 individuals). Among the 51 cases of perforated appendicitis, 70.59% had elevated bilirubin levels of above 20 μmol/L. Significantly more patients with appendiceal perforation had hyperbilirubinemia than non-perforated appendicitis (70.59% vs. 19.03%, p < 0.001). Bilirubin had higher specificity (94.29%) for detecting non-perforated appendicitis than normal appendices (odds ratio = 3.88), while WCC and CRP showed higher sensitivities. WCC had a sensitivity of 73.28% and a specificity of 42.86%, and CRP had a sensitivity of 76.53% and a specificity of 60.00%. When comparing perforated appendicitis with non-perforated appendicitis, bilirubin showed a specificity of 80.97% and an odds ratio of 10.21. The likelihood of a patient with hyperbilirubinemia having perforated appendicitis was more than 10 times higher than those without appendiceal perforation, suggesting it to be a potential indicator for appendiceal perforation. WCC showed a specificity of 26.72% and an odds ratio of 4.28, while CRP had a specificity of 23.48% and an odds ratio of 4.91. Conclusions The significant association between bilirubin levels and appendicitis highlights its potential as a valuable marker for predicting appendicitis and appendiceal perforation. The simplicity, cost-effectiveness, and diagnostic value of bilirubin assessment support its routine use in suspected cases of acute appendicitis.