Perianal mass and recurrent cellulitis due to Enterobius vermicularis.

A unique case of enterobiasis presenting as recurrent cellulitis and a perianal mass in a six-year-old girl is reported. Complicated perianal lesions due to Enterobius are unusual. Only 10 previous cases are known, with unclear pathogenesis in most of them, although mucosal breaches and perianal crypt or gland entry have been postulated. The association of the mass in this case with a deep crypt, and the histopathologic finding of squamous epithelium focally surrounding the granulomatous reaction to the Enterobius eggs suggest that the worm entered the perianal tissues via a crypt. Local secondary bacterial infection can cause significant morbidity. Surgical excision of such granulomatous mass lesions is necessary in symptomatic or complicated cases.