Hyperbilirubinemia as a Predictor of Appendiceal Perforation: A Systematic Review and Diagnostic Test Meta-Analysis

Misdiagnosis of the severity of acute appendicitis may lead to perforation and can consequently result in increased morbidity and mortality. In this study, the role of hyperbilirubinemia as a predictor of perforation is assessed by performing a meta-analysis of diagnostic accuracy.

A systematic search of the literature published over the past 20 years was performed using the EMBASE, PubMed, Cochrane library, and Google Scholar databases.

Low values of sensitivity, specificity, and diagnostic odds ratio (DOR) were detected: 0.21 (95% confidence interval (CI): 0.13 - 0.30, standard error (SE) = 0.43), 0.27 (95% CI: 0.15 - 0.43, SE = 0.73), and 0.10 (95% CI: 0.3 - 0.28, SE = 0.05), respectively. The positive likelihood ratio (PLR) was low (0.29 (95% CI: 0.27 - 0.91, SE = 0.76)), whereas the negative likelihood ratio (NLR) was high (2.88 (95% CI: 1.66 - 5.14, SE = 0.10)). The hierarchical summary receiver operating characteristic curve was positioned towards the lower right corner, and the area under the curve was 0.19, both indicating a low level of overall accuracy and discrimination. Compared with the PLR, the negative inverse likelihood ratio (1/LR^-) indicated that a positive result has a greater impact on the odds of disease than does a negative result.

Hyperbilirubinemia alone is not a reliable tool to predict perforation. Future studies should investigate whether the combined predictive values of bilirubin, C-reactive protein (CRP), and white blood cells are a more effective diagnostic tool.