Is Enterobius vermicularis infestation associated with acute appendicitis?

PURPOSE: Enterobius vermicularis might be seen in specimens of patients who underwent surgery due to acute appendicitis. There is still debate as to E. vermicularis infestation causes acute appendicitis. The primary aim of this study is to determine the incidence of E. vermicularis infestation, and the secondary aim is to determine the possible role of E. vermicularis in pathogenesis of appendicitis as well as the adequacy of demographic data and laboratory values in predicting infestation preoperatively. METHODS: A retrospective investigation was conducted with all patients who underwent appendectomy due to acute appendicitis in a secondary care center. Patients with E. vermicularis were compared with 24 controls that underwent appendectomy during the same time period. Demographic data, preoperative white blood cell (WBC) count, eosinophil counts, and histopathological findings for both groups were analyzed and compared. RESULTS: Enterobius vermicularis was detected in the appendectomy materials in 9 of 1446 patients (0.62 %). Histopathologically, only one of nine patients had acute appendicitis while the others were diagnosed with lymphoid hyperplasia. There were no statistically significant differences between the groups except WBC count. However, the WBC count was significantly (p < 0.05) lower in the group which was detected E. vermicularis. CONCLUSIONS: Enterobius vermicularis is rarely associated with the histopathological findings of acute appendicitis. Also eosinophil count and elevation of white blood counts are inadequate for predicting preoperative E. vermicularis.