Clinical and laboratory methods in diagnosis of acute appendicitis in children.

Aim: To compare the diagnostic accuracy of clinical examination, white blood cell and differential count, and C-reactive protein as routine tests for acute appendicitis with that of interleukin-6 (IL-6) and ultrasonography.

Methods: Eighty-two children were admitted to the Department of Pediatric Surgery and Intensive Care, Ljubljana, Slovenia because of suspected acute appendicitis. Among them, 49 children underwent surgery for acute appendicitis and 33 had abdominal pain but were not treated surgically and were diagnosed with non-specific abdominal pain or mesenteric lymphadenitis on sonography. Clinical signs of acute appendicitis were determined by surgeons on admission. White blood cell count and differential and serum concentrations of C-reactive protein and IL-6 were measured and abdominal ultrasonography was performed.

Results: Ultrasonography showed the highest diagnostic accuracy (92.9%; 95% confidence interval [CI], 84.5%-98.0%, Bayes' theorem), followed by serum IL-6 concentration (77.6%; 67.1-86.1%, receiver-operating characteristic [ROC] curve analysis), clinical signs (69.5%; 59.5-79.0%, Bayes' theorem), white blood cell count (68.4%; 57.2-78.3%, ROC curve analysis), and serum C-reactive protein concentration (63.7%; 52.174.3%, ROC curve analysis). Ultrasonography achieved also the highest specificity (95.2%) and positive (93.8%) and negative (93.3%) predictive values, whereas clinical signs showed the highest sensitivity (93.9%).

Conclusion: Ultrasonography was a more accurate diagnostic method than IL-6 serum concentration, laboratory marker with the highest diagnostic accuracy in our study, and hence it should be a part of the diagnostic procedure for acute appendicitis in children.