Application with repeated serum biomarkers in pediatric appendicitis in clinical surgery

PURPOSE: To apply the repeated serum laboratory tests in diagnosing acute appendicitis in children with suspected appendicitis. METHODS: From 2005 to 2007, we prospectively collected 217 pediatric patients with clinically suspected appendicitis. The repeated serum laboratory tests were measured 6 h later and the changes in serum inflammatory biomarkers analyzed. Significant changes in serum parameters between primary and repeated examinations were selected as the discriminating variables. The receiver operating characteristic (ROC) curves were used to determine the cutoff values of the changes between two examinations in predicting appendicitis. RESULTS: Based on the ROC analysis, the change in the serum parameters could include simple appendicitis when the change in neutrophils (delta neutrophils) was >23.5% and delta C-reactive protein (CRP) was >118 mg/L; but for the exclusion of simple appendicitis, delta neutrophils was -44% or under and delta CRP was -10.0 mg/L or under. For perforated appendicitis, delta white blood cell counts, delta neutrophils, delta bands and delta CRP were all significant discriminators. However, based on analysis of the area under the ROC curve (AUC), only delta CRP had the greatest AUCs in predicting both simple and perforated appendicitis. The cutoff point of delta CRP was taken as 4.80 mg/L in distinguishing simple appendicitis from other acute abdominal diseases, and taken as 9.45 mg/L in predicting perforated appendicitis. CONCLUSIONS: Significant change between primary and repeated serum laboratory tests may serve as a helpful method in predicting acute appendicitis in children with suspected appendicitis.