Lack of utility of measuring serum bilirubin concentration in distinguishing perforation status of pediatric appendicitis.

BACKGROUND: Pediatric appendicitis is a common, potentially serious condition. Determining perforation status is crucial to planning effective management. PURPOSE: Determine the efficacy of serum total bilirubin concentration [STBC] in distinguishing perforation status in children with appendicitis. METHODS: Retrospective review of 257 cases of appendicitis who received abdominal CT scan and measurement of STBC. RESULTS: There were 109 with perforation vs 148 without perforation. Although elevated STBC was significantly more common in those with [36%] vs without perforation [22%], the mean difference in elevated values between groups [0.1mg/dL] was clinically insignificant. Higher degrees of hyperbilirubinemia [>2mg/dL] were rarely encountered [5%]. Predictive values for elevated STBC in distinguishing perforation outcome were imprecise [sensitivity 38.5%, specificity 78.4%, PPV 56.8%, NPV 63.4%]. ROC curve analysis of multiple clinical and other laboratory factors for predicting perforation status was unenhanced by adding the STBC variable. Specific analysis of those with perforated appendicitis and percutaneously-drained intra-abdominal abscess which was culture-positive for Escherichia coli showed an identical rate of STBC elevation compared to all with perforation. CONCLUSIONS: The routine measurement of STBC does not accurately distinguish perforation status in children with appendicitis, nor discern infecting organism in those with perforation and intra-abdominal abscess.