Receiver-operating characteristic analysis of leukocyte counts and serum, C-reactive protein levels in children with advanced appendicitis

Purpose. To assess the diagnostic value of the white blood cell count (WBC) and serum C-reactive protein (CRP) level in children with advanced appendicitis. Methods. We reviewed 289 children ranging in age from 3 to 15 years old, who underwent appendectomy in our hospital between 1993 and 2003. The advanced appendicitis group consisted of patients with associated perforation, abscess formation, or purulent ascites, and the simple appendicitis group consisted of patients who underwent uncomplicated appendectomy. We compared the age, sex, duration of abdominal pain before surgery, preoperative WBC and CRP level, and hospital stay in the two groups. We analyzed the diagnostic value of WBC and CRP level using a receiver-operating characteristic (ROC) curve. Results. The children in the advanced appendicitis group had a significantly longer duration of pain, a higher serum CRP level, and longer hospitalization than those in the simple group. The serum CRP levels had Good diagnostic value in differentiating between the advanced and simple groups. Both the CRP level and the WBC in the patients who suffered abdominal pain for longer than 48h before surgery had diagnostic value in differentiating between the advanced and simple groups. Conclusion. These findings suggest that increased values of CRP and WBC more than 48h after the onset of acute abdominal symptoms are indicators of advanced appendicitis.