Hyperbilirubinemia as an Indicator of Perforated Acute Appendicitis in Pediatric Population: A Prospective Study.

Background: This prospective cohort study aimed to investigate the association of hyperbilirubinemia with perforated appendicitis in the pediatric population. Patients and Methods: A total of 284 children in whom the diagnosis of acute appendicitis was established were included in this study. The patients were allocated in study groups in regard to operative findings. The first study group included patients who had perforated appendicitis (n = 64; 22.5%) whereas the patients in the second group had simple appendicitis (n = 220; 77.5%). Blood samples for serum bilirubin levels and acute inflammatory markers were taken before the patients underwent surgery. The primary outcome of the study was to investigate whether the level of serum bilirubin should be used to distinguish between simple and perforated appendicitis. Results: The median level of serum bilirubin in children with perforated appendicitis was 27 mcmol/L whereas the patients with simple appendicitis had lower median levels of serum bilirubin (10 μmol/L; p < 0.001). An area under the receiver operating characteristic (ROC) curve for total serum bilirubin was 0.876 (95% confidence interval [CI], 0.820-0.929) in the patients who had a perforated appendicitis. An ROC analysis showed the best sensitivity (92%) and specificity (77.3%) for a cutoff value of 15.5 mcmol/L for total serum bilirubin (p < 0.001). Hyperbilirubinemia at admission was found in 35 patients (54.7%) with complicated appendicitis and in 14 patients (6.4%) with non-perforated appendicitis (p < 0.001). The modeling of collected data by multivariable logistic regression identified serum bilirubin concentration (odss ratio [OR] = 1.12; 95% CI, 1.07-1.18; p < 0.001), serum sodium concentration (OR = 0.64; 95% CI, 0.51-0.81; p < 0.001), body temperature (OR = 2.48; 95% CI, 1.05-0.84; p < 0.001), and duration of symptoms (OR = 1.06; 95% CI, 1.02-1.09; p < 0.001) as risk factors for perforated appendicitis. Conclusion: Elevateds level of total serum bilirubin may be useful as an indicator of perforated appendicitis in children. Levels of bilirubin in serum is an inexpensive, simple, and available laboratory marker and should therefore be recommended in the initial evaluation for acute appendicitis in pediatric patients.