Diagnostic value of hyperbilirubinemia as a predictive factor for appendiceal perforation in acute appendicitis

Abstract Background Appendiceal perforation in patients with acute appendicitis may cause a variety of potentially life-threatening complications. Escherichia coli endotoxin has been shown to impact physiological bile flow in vivo. This had led to the theory that hyperbilirubinemia in patients with appendicitis may have a predictive potential for the preoperative diagnosis of appendiceal perforation. The aim of this retrospective study was to investigate the diagnostic value of hyperbilirubinemia as a preoperative laboratory marker for appendiceal perforation in patients with acute appendicitis. Methods We identified 538 patients (306 female; 232 male, mean age, 35.6 y) with histologically proved acute appendicitis who underwent laparoscopic or conventional appendectomy between January 2004 and December 2007 in a surgical department of an academic teaching hospital. A retrospective multiple chart review of the medical records including laboratory values and histologic results was conducted. Results The mean bilirubin level of all patients was .9 mg/dL (±.6 SD mg/dL; range, .1–4.3 mg/dL; median, .7 mg/dL). Patients with appendiceal perforation, however, had a mean bilirubin level of 1.5 mg/dL (±.9 SD mg/dL; range, .4–4.3 mg/dL; median, 1.4 mg/dL), which was significantly higher than those with a nonperforated appendicitis ( P < .05). The specificity of hyperbilirubinemia for appendiceal perforation was .86 compared with .55 for white blood count and .35 for C-reactive protein. Sensitivity was .7 compared with .81 for white blood count and .96 for C-reactive protein. Conclusions Patients with hyperbilirubinemia and clinical symptoms of appendicitis should be identified as having a higher probability of appendiceal perforation than those with normal bilirubin levels.