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Cet abstract a été assigné à session SBO-BOG free papers: Medische retina en Uveïtis/ Rétine médicale et uvéite

Titre	Ocular Onchocerciasis: Wolbachia play a main role in causing river blindness
Abstract Nr.	140

But	The parasitic worm Onchocerca volvulus releases millions of offspring (microfilariae) which migrate through the skin and can enter the eye. While alive, the microfilariae appear to cause little or no inflammation, as being in the anterior chamber. However, when they die, the host response to degenerating worms can result in ocular inflammation that causes progressive loss of vision.
Méthodes	The current mainstay of mass treatment by the World Health Organization's African Programme for Onchocerciasis Control (APOC) is ivermectin, an antiparasitic agent that kills microfilariae and inhibits the growth and proliferation of offspring for several months at a time; it targets mature microfilariae. But the treatment with ivermectin does not cure the disease. Ivermectin + doxycycline cause sterility in adult worms and thereby directly suppress the embryonic development of the worm. Studies have shown that the combination of ivermectin and doxycycline significantly enhanced ivermectin-induced suppression of microfilariae, effectively blocking disease transmission for as long as years, possibly irreversibly.
Résultats	Onchocerca volvulus and other nematodes harbour endosymbiotic Wolbachia bacteria throughout their life cycles, and they are passed onto the next generation of worms through the oocyte, much like an inherited characeristic. The worm relies on these intracellular bacteria for its homeostasis.
Conclusion	It becomes increasingly clear now that Wolbachia play a main role in the pathogenesis of ocular onchocerciasis in the human host. Using a mouse model of corneal inflammation to study the pathogenesis of the disease, data indicate that keratitis could not be triggered by the nematode extracts which lacked the Wolbachia bacteria.

Auteur 1

Nom	KLUXEN
Initiales	G
Institut	Germany
Ville	Wermelskirchen

Auteur 2

Nom	HOERAUF
Initiales	A
Institut	Germany
Ville	Bonn