C-reactive protein in the differential diagnosis of the acute abdomen, especially acute appendicitis.

Serum C-reactive protein (CRP) was qualitatively determined before surgery in 189 patients undergoing appendicectomy. The sensitivity, specificity, negative predictive value and overall accuracy of CRP were assessed: CRP had a high specificity (76.3%) but a sensitivity of only 39.7%. CRP may be of value in the assessment of acute abdominal pain, by helping to exclude from surgery those patients with normal appendices.