Enterobius vermicularis: A cause or an incidental finding in pediatric appendicitis?

Objectives: This study aimed to investigate the incidence of Enterobius vermicularis (E. vermicularis) in appendectomy specimens and its contribution to the pathogenesis of appendicitis. Patients and methods: The files of appendectomy specimens from patients who had E. vermicularis between June 2016 and June 2022 were reviewed retrospectively. The samples of patients whose appendectomy specimens showed E. vermicularis were analyzed in three groups according to the results of histopathological evaluation: reactive lymphoid hyperplasia, acute appendicitis, and perforated appendicitis. Results: The files of 1,334 patients were examined, and E. vermicularis was found histopathological in 24 (1.8%) patients (15 males, 9 females; mean age: 11.2±2.9 years; range, 7 to 17 years). Histopathological examination of appendectomy specimens revealed reactive lymphoid hyperplasia in 15, acute appendicitis in six, and perforated appendicitis in three. Only neutrophil counts were significantly different in patients with reactive lymphoid hyperplasia and acute appendicitis (p<0.05). Conclusion: The high rate of histopathological reactive lymph nodes in appendectomy specimens with E. vermicularis suggests that this parasite is found incidentally in the appendix. Differentiating enterobiasis from true appendicitis may prevent unnecessary appendectomies.