Unusual presentation of Enterobius vermicularis in conjunctival sac

Rare presentations of ocular enterobiasis - Case reports

Enterobius vermicularis, also known as pinworm or threadworm, is a large intestinal nematode which has a high prevalence among children and peripubertal age in our country. Transmission usually occurs by autoinfection like finger contamination of the embryonated eggs deposited by the gravid female worm on the perianal and perineal region. Globally, only a few reports are there regarding the isolation of the parasite from extra-intestinal sites. These are two rare case reports of ocular enterobiasis. The first case was a middle-aged female and the second one was a 14-year-old girl, both of whom were referred from other tertiary care hospitals to Calcutta School of Tropical Medicine and who presented with discharge of live motile worms from their eyes (conjunctiva). In both the cases, identification was done by saline wet mount and direct microscopy of a gravid female worm. Plano-convex embryonated eggs were also observed. The oval embryonated eggs, plano-convex in shape, and the gravid female, with its cervical alae near the anterior end and straight thin pointed tail, were identified under the microscope. Although E. vermicularis is a very common large intestinal parasitic infestation of children and adolescents, it can also rarely be isolated from unusual sites, which should be taken into account for effective diagnosis and treatment.