THE ACCURACY OF C-REACTIVE PROTEIN IN DIAGNOSING ACUTE APPENDICITIS -A METAANALYSIS

The aim of the study was to review the literature on the accuracy of C -reactive protein (CRP) in diagnosing acute appendicitis. All the rele vant articles found by searching Medline and the Science Citation Inde x were reviewed. We used summary receiver operating characteristic (SR OC) curve analysis to describe the central tendency of the studies and to assess potential sources of variability. We included 22 articles w ith a total number of 3436 patients. The sensitivity ranged from 0.40 to 0.99, and the specificity from 0.27 to 0.90. The cut-off values for a positive test varied from 5 to 25 mg l(-1). SROC curve analysis sho wed that CRP performed significantly better in acute abdomen populatio ns (11 studies) than in populations already selected for appendectomy (11 studies). The diagnostic accuracy of CRP tended to be a little inf erior to that of total leukocyte count (13 studies). CRP is a test of medium accuracy in diagnosing acute appendicitis. The formerly distrac tingly wide range of sensitivity and specificity is at least partly du e to variations in cut-off values and to differences in study populati ons. However, definitive conclusions on the clinical usefulness of the test could not be drawn.