ASSESSMENT OF PERITONISM IN APPENDICITIS

The aim of this study was to evaluate the accuracy of different method s of demonstrating right iliac fossa peritonism in appendicitis. The m ethods used were cat's eye symptom (pain on going over a bump in the r oad), cough sign, right iliac fossa tenderness, percussion tenderness, rebound tenderness and guarding. A series of 100 consecutive patients with a median age of 25 years (range 4-81 years), presenting with rig ht iliac fossa pain were studied prospectively; the male:female ratio was 39:61. In all, 58 patients underwent operation, 44 had appendiciti s confirmed on histology. Fourteen patients had a normal appendix remo ved; 11 were women aged between 16 and 45 years. Cat's eye symptom and cough sign were sensitive indicators of appendicitis (sensitivity 0.8 0 and 0.82, respectively), but were not specific (specificity 0.52 and 0.50, respectively) and therefore inaccurate (accuracy 64%). Percussi on tenderness was less sensitive (sensitivity 0.57) but more specific (specificity 0.86). Rebound tenderness proved to be sensitive (sensiti vity 0.82), specific (specificity 0.89) and accurate (accuracy 86%). T hus, rebound tenderness had a positive predictive value of 86% compare d with 56% and 57% for cough sign and cat's eye symptom, respectively. In the difficult diagnostic group of young women, the positive predic tive value of rebound tenderness was 88% compared with 58% and 56% for cat's eye symptom and cough sign. Appendicitis remains a difficult di agnosis, particularly in young women. Rebound tenderness still has an important role to play in clinical assessment.