Elevated serum bilirubin in assessing the likelihood of perforation in acute appendicitis: A diagnostic meta-analysis

Hyperbilirubinemia associates with perforated acute appendicitis, but the precise test characteristics have not been determined by sufficiently powered studies.A systematic literature search of reports on hyperbilirubinemia in acute appendicitis was performed. After review and quality assessment of eight studies encompassing a total of 4974 patients the sensitivity, specificity and other measures of accuracy of hyperbilirubinemia as a predictor of perforation in acute appendicitis were pooled using a random-effects model.Summary estimates for hyperbilirubinemia (cutoff 1 mg/dl) as a predictor of perforation in acute appendicitis were as follows: sensitivity, 0.49 (95% confidence interval [CI], 0.45–0.52); specificity, 0.82 (95% CI, 0.80–0.83); positive likelihood ratio, 2.51 (95% CI, 1.58–4.00); negative likelihood ratio, 0.58 (95% CI, 0.44–0.76); diagnostic odds ratio was 4.42 (95% CI, 2.21–8.83). In summary receiving operating characteristic (SROC) analysis, the area under curve was 0.73.The presence of hyperbilirubinemia does not alone distinguish a perforation in acute appendicitis. Serum bilirubin level is of some value as a predictor of appendiceal perforation. Patients with hyperbilirubinemia combined with symptoms and signs consistent with severe acute appendicitis should be considered for early appendectomy.