The adult worms lodge in the lymphatics obstruct lymph flow resulting in painless pitting oedema of distal tissue. Often patients present with painless leg swelling which progresses during the day and resolves overnight.
With time and without treatment, the lymphatics become permanently obstructed by granulomata and fibrosis. Chronic lymphoedema (elephantiasis) is non-pitting and results in thick, lichenified skin.
Chronic obstruction to lymph flow may result in:
- chylous ascites
Recurrent bacterial lymphangitis is a common complication, usually starting proximally and spreading distally. Abscess formation may occur, resulting in discharging ulcers along the line of the lymphatics. Epididymitis is another complication.
The limbs, external genitalia and breasts are the typical regions affected by filarial lymphoedema.
Pulmonary hypersensitivity to the microfilariae of W. bancrofti may result in tropical pulmonary eosinophilia.
Last reviewed 01/2018