Description

A 6-year-old male child presented with intermittent abdominal pain and alternating bowel since 1 year. Lab tests resulted negative, except for high erythrocyte sedimentation rate. Stool studies—occult blood and microbiology—resulted unremarkable. Symptoms were persistent and started impairing the child's life everyday. Despite failure to thrive, abdominal pain at night was not registered. Abdomen ultrasound showed thickening of distal ileum, and mildly enlarged mesenteric lymph nodes. At lower endoscopy in the distal ileum worms crawling on the wall were seen (see Video 1). Direct microscopy showed Enterobius vermicularis (EV). Random biopsies of the colon revealed lymph-node hyperplasia. The patient was twice successfully treated with mebendazole (200 mg/day).

EV—pinworm—is the most common helminthes infection in Western Europe and North America.1 The infestation occurs worldwide, affecting all socioeconomic groups, particularly school-aged children. The interhuman transmission is oro-faecal. Most patients are asymptomatic, and when symptoms are present, peri-anal itching—especially at night—is the most common clinical feature.

The child came to our observation after first-line investigations. Stool exams (microbiology+scotch-test) should have been repeated before performing lower endoscopy as indicated for abdominal pain with ‘red-flags’,2 such as in the suspicion of inflammatory bowel diseases (IBDs). Infectious diseases must be strongly excluded before thinking of inflammatory ones. With the improvement in scientific knowledge and in diagnostic accuracy, it is easy to focus the attention on major diseases despite minor ones. In our case we performed endoscopy in the suspicion of IBDs (prevalence 0.6%)3 but diagnosed parasitosis (prevalence 30–40%).1