Pinworm Infestation Mimicking Crohns’ Disease

We here report a case of a young man who presented to his general practitioner with diarrhea. Inflammatory bowel disease was suspected and a colonoscopy showed aphthous lesions suggestive of Crohns’ disease but biopsies revealed eggs of Enterobius vermicularis. When treated for this parasite, his symptoms were alleviated and a followup colonoscopy revealed a normal colon and distal ileum. Enterobius vermicularis is the most common parasite worldwide and has been attributed with many different presentations and pathologies. It is therefore necessary to maintain vigilance, even in high-income countries, in order to diagnose patients with one of the many atypical presentations of pinworms. 1. Introduction In Scandinavia, the presence of aphthous ulcerations and erosions in the distal ileum and caecum is usually a manifestation of Crohns disease. However numerous differential diagnoses exist and histopathological confirmation is required in order not to give the patient the lifelong diagnosis of Crohns disease inaccurately. Enterobius vermicularis is the most common helmintic parasite known, affecting all members of society regardless of age, gender, and social status [1]. They typically reside in the caecum, appendix and distal ileum, where they adhere to the mucosa [2]. Although many infections are asymptomatic, perianal itching, especially at night, is the most common symptom [1]. However there are a lot of atypical presentations described in the literature, for example, infections of the kidneys [3] and infections of the female genital tract [4] as well as many other presentations. Typically the diagnosis rests upon applying cellophane or scotch tape to the perianal skin in the morning, removing it, and detecting eggs using the microscope [1, 5]. The worms can however be seen during endoscopy [6], and both the worm and its eggs can be found in histological specimens [5, 7]. Once diagnosed the infection is eradicated with two doses of Mebendzole two weeks apart as well as hygienic measures [8]. We here present a case of a young man with an Enterobius vermicularis infection which mimics Crohns disease. 2. Case Presentation A 22-year-old man presented to his GP with an exacerbation of diarrhea during the past two months. He reported that he usually had diarrhea once or twice a week mostly on weekends and on daytime normally beginning as abdominal cramps that was relieved by defecation. During the past two months, he had been having an increased amount of watery-thin diarrhea 5-6 days a week. He now had symptoms also during the night and with no relation to