Paracolic Lymph Nodes: A Novel Diagnostic Sign For Pediatric Perforated Appendicitis?

Abstract

Objective: Acute appendicitis is the most common reason for emergency abdominal surgery in pediatric population.Ultrasonography (US) is a widely used modality to diagnose acute appendicitis. Despite its success in diagnosing acuteappendicitis, US have been reported to have a poor diagnostic accuracy to detect perforated appendicitis. We havefrequently encountered lymph nodes around transvers colon in pediatric perforated appendicitis cases. We mainly aimto evaluate the accuracy of paracolic lymph node presence as a new diagnostic marker for perforated appendicitis.Material and Methods: We have evaluated the US reports and/or images of the patients referred to radiologydepartment with a clinical suspicion of acute appendicitis. Paracolic lymph node presence and sonographic findingsindicating perforated appendicitis were recorded. Patients were divided into three subgroups according to their finaldiagnosis: Acute appendicitis, perforated appendicitis, others.Results: Mean age of the population was 14.9±2.3 years. There were 300 acute appendicitis cases, 71 perforatedappendicitis cases, and 92 other diagnosis cases (4 lymphoid hyperplasia, 88 normal appendix). Rates of lymphnode presence in paracolic area were 41/300 (13.6%) in acute appendicitis subgroup, 58/71 (81.6%) in perforatedappendicitis subgroup, and 4/92 (4.34%) in other diagnosis subgroup. A longest diameter of a paracolic lymph node >8.5 mm seemed to be a good predictor for perforated appendicitis diagnosis (sensitivity 85%, specificity 77%).Conclusion: We showed a statistically significant association between paracolic lymph node presence and perforatedappendicitis. This sign can serve to confirm perforated appendicitis diagnosis over simple appendicitis.