Predictive Value of C-reactive Protein for Diagnosis of Acute Perforated and Non-perforated Appendicitis

ABSTRACT

PURPOSE: This study was to determine the relationships between C-reactive protein (CRP) level of acute perforated and nonperforated appendicitis. METHODS: We retrospectively investigated 200 patients who was diagnosed to appendicitis in emergency medical center from January 2005 to August 2005. All patients were operated for suspected acute appendicitis and diagnosis was confirmed by histology after operation. The patients were divided two groups group A with nonperforated appendicitis and group B with perforated appendicitis. We assessed and compared epidemiologic, clinical and laboratory data between two groups. For comparison of diagnostic value, the receiver operating characteristic (ROC) curve and the logistic regression analysis were done. RESULTS: Of the 200 patients, 149 patients were group A, and 51 patients were group B. The mean CRP level in the group B was higher than in patients with group A (109.25+/-87.18 mg/L vs 20.39+/-39.34 mg/L, p<0.05). Also WBC counts was higher in the group B (15.43+/-5.58x1000/microliter vs 12.47+/-4.5x1000/microliter, p<0.05). Though the area under the ROC curve (AUC) of CRP level was greater than WBC counts (0.853 vs 0.659), so CRP level was found to be significantly superior to WBC count in predicting perforated appendicitis. In logistic regression analysis, CRP level (odds ratio 1.024, 95% CI 1.016 to 1.035) was only independent predictor of perforated appendicitis. CONCLUSION: Increased CRP level in patients who were suspected appendicitis in emergency medical center was valuable in predicting perforated appendicitis. In such circumstances, we should consider the necessities of preoperative antibiotics, the surgical techniques and the early aggressive management for postoperative complications.