Loiasis is caused by Loa loa (eye worm) and is a classic instant diagnosis when the adult worms are seen during subconjunctival migration. This may present with a compliant of eyelid swelling and a sensation of motion in the eyeball. The other characteristic presentation is Calabar swellings. The patient may well have a marked eosinophilia. The vectors are mango flies or deerflies (Chrysops spp.). Occasionally the adult worm is found in the anterior chamber of the eye.
Once ingested by a Chrysops fly, the microfilariae become infective in approximately 10 to 12 days. Humans are infected by Chrysops bites. The adult worm develops in about 3 to 12 months, and can survive up to 17 years.
- Ivermectin 150 to 200 µg/kg
- Surgical excision
- ↑ Samarasinghe S, Pathirana S. A juvenile filarial worm, Wuchereria bancrofti, extracted from the vitreous of the eye: the first report in the world literature. The Ceylon medical journal. 2005 Dec; 50(4):167-8.
- ↑ Gardon J, Gardon-Wendel N, Demanga-Ngangue Kamgno J, Chippaux JP, Boussinesq M. Serious reactions after mass treatment of onchocerciasis with ivermectin in an area endemic for Loa loa infection. Lancet. 1997 Jul 5; 350(9070):18-22.(Link to article – subscription may be required.)