Enterobius vermicularis infection of the fallopian tube in an infertile female.

Enterobius vermicularis (EV) is the most common nematode to infect humans. It inhabits the intestinal lumen, but rare, ectopic infections have been documented. The female genital tract is the most common ectopic site. We present a unique case of an EV infection of the fallopian tube resulting in inflammation, tubal obstruction, and infertility. A 30-year-old woman presented with infertility. Investigations included a laparoscopy with hydrotubation using methylene blue dye. This showed a left fallopian tube obstruction and extensive pelvic adhesions. A left salpingectomy was performed. Microscopic examination of the fallopian tube revealed numerous calcified and non-calcified ova associated with granulomatous reaction. The microscopic features were compatible with EV infection. Ectopic EV infections of the female genital tract result when the gravid female worm migrates from the perianal area to the vagina and ascends through the uterus and fallopian tubes to the peritoneal cavity. Microscopic examination of these ectopic sites can reveal adult worms or ova with granulomata formation, eosinophilic infiltrate, chronic inflammatory reaction, and fibrosis. The ova have a characteristic asymmetric oval configuration with flattening on one side. We postulate that our patient's salpingitis due to EV with accompanying fibrosis is a cause of her infertility.