Lymphatic filariasis

**Definition:** Infestation by filarial nematodes of the genera Wuchereria and Brugia. It is acquired via transcutaneous injection of larvae by mosquitoes previously infested with microfilariae from the blood of a human host. The adult worms live in the lymphatics but release microfilariae into the bloodstream to complete the life cycle of the parasite. Clinical disease occurs in only a minority of those infected. In the acute stage this may present as an acute painful adenolymphangitis with fever. Chronic infestation causes progressive obstruction of lymphatic vessels and can result in disfiguring lymphoedema (elephantiasis), particularly of the genitalia and lower extremities.

**Long definition:** Lymphatic filariasis is a parasitic disease caused byWuchereria bancrofti and filarioidea of the Brugia genus. Early clinical signs revolve mainly around lymphangitis, which when it begins in limbs and progresses in a centrifugal manner. Later symptoms are caused by obstruction of the lymphatic vessels. Elephantiasis only appears after years of high-level infection.

**Exclusions:** - Lymphoedema due to lymphatic filariasis