Unusual endoscopic and microscopic view of Enterobius vermicularis: a case report with a review of the literature.

Enterobius vermicularis has the broadest geographic range of any helminth and is the most common intestinal parasite seen in the primary care setting. Underappreciated is the fact that it is not always a benign disorder and could even cause life-threatening medical problems. Visualization of the actual worms during endoscopy is probably underappreciated in part because endoscopists have never actually seen the worm and/or are not actively looking for, or anticipating, worms. This report describes a case of worm infection as documented during colonoscopy and confirmed by microscopy. The gross and microscopic appearance of the worm is described. Literature regarding the wide range of gastrointestinal and nongastrointestinal manifestations, including potentially life-threatening illnesses, as well as treatment options, are also reviewed.