Acute appendicitis caused by Enterobius vermicularis in an 8-year-old child: a case report

Enterobius vermicularis is a common pediatric parasite, and appendicitis is a frequent surgical emergency in children; however, it is uncommon for E. vermicularis infection to be the underlying cause. An 8-year-old girl presented with fever, vomiting, and right lower quadrant abdominal pain. Laboratory evaluation demonstrated leukocytosis (WBC 19.3 × 10 9 /L) with neutrophilia (14.4 × 10 9 /L) and eosinophilia (1.0 × 10 9 /L). Contrast-enhanced CT revealed a dilated, fluid-filled appendix with mucosal thickening and a distal appendicolith, consistent with acute appendicitis. She underwent uncomplicated laparoscopic appendectomy and was discharged the following day, tolerating a regular diet. Histopathology confirmed acute appendicitis with E. vermicularis organisms present. She was prescribed pyrantel pamoate oral suspension 50 mg/mL, 4.8 mL by mouth as a single dose, with a repeat dose scheduled two weeks later, and all household contacts were advised to undergo treatment. Notably, she had a history of recurrent conjunctivitis and vulvovaginitis, prompting referral to ophthalmology to evaluate for rare extraintestinal involvement. Parasitic infection of the appendix should be suspected in pediatric patients with acute appendicitis and eosinophilia to ensure complete treatment with anti-parasitic therapy.