Diagnostic Value of C-reactive Protein in Complicated Appendicitis

Early detection of appendicitis has increased due to development of computed tomography and ultrasonography, yet we are frequently meeting complicated appendicitis, including perforation, abscess and a gangrenous appendicitis due to delayed diagnosis. For that reason, we want to evaluate predictive factors for the complicated appendicitis.

A total of 128 patients with appendicitis, after 13 patients with a duration of under 12 hours and 15 patients with pathological non-appendicitis were excluded from 156 patients, who visited Kwangju Christian Hospital from November 2008 to November 2010 were retrospectively reviewed.

There were 62 patients (48.3%) with simple appendicitis and 66 patients (51.7%) with complicated appendicitis. In univariate analysis, age (P < 0.001), C-reactive protein (P < 0.001) and the diameter of the appendix (P = 0.006), were found to be significant. Multivariate analysis demonstrated that C-reactive protein was an independent predictor for complicated appendicitis (odds ratio, 1.371; 95% confidence interval, 1.155 to 1.628; P < 0.001). The cut-off value of C-reactive protein was set at 7.05 mg/dL by using receiver operating characteristic curve (0.805; sensitivity, 57.6%; specificity, 98.3%).

This study suggests that if C-reactive protein is above 7.05 mg/dL, immediate and proper management should be performed due to a high probability of complicated appendicitis, especially in young children or elderly patients who frequently present with vague symptoms.