The Simple Clinical Diagnostic Triad in Acute Appendicitis: Re-examined

Abstract

Introduction: The numerous clinical and radiologic scoring systems available are a testament to the challenges of diagnosing acute appendicitis. As the name implies, the simple acute appendicitis clinical diagnostic triad is simple and userfriendly. Its reproducibility remains to be demonstrated. Aim: To validate the simple clinical diagnostic triad of right lower quadrant abdominal tenderness, anorexia and migratory abdominal pain for the diagnosis of acute appendicitis in a District General Hospital. Materials and Methods: This was a retrospective review of consecutive appendicectomies undertaken over a 4-month period, for patients who were 18 years and older. Acute appendicitis was proven histologically. The patients’ preoperative symptoms, signs and biochemical parameters were analysed. Sensitivity, specificity, Positive Predictive Value (PPV) and Negative Predictive Value (NPV) were calculated. Outcomes were compared using Fisher’s exact test. Results: A total of 92 appendicectomies were undertaken during the study period. The histological diagnoses included acute appendicitis (75), normal appendix (14), carcinoid (1), lymphoid hyperplasia (1) and spirochete (1). Of the 75 patients with acute appendicitis, right lower quadrant tenderness was present in 73, anorexia in 66 and migratory pain in 57 patients. The simple clinical triad (all three parameters) showed a sensitivity of 69.3%, 64.7% specificity, 89.7% PPV and 32.4% NPV. Conclusion: The triad of right lower quadrant tenderness, anorexia and migratory abdominal pain shows consistently high PPV in the diagnosis of acute appendicitis.

Keywords

• abdominal pain
• anorexia
• predictive value
• tenderness