Lymphatic Filariasis

Early in the infection, people may have symptoms for 4 to 7 days. They may have a fever, swollen lymph nodes in the armpits and groin, and pain in the limbs and groin. Pus may collect in a leg and drain to the skin's surface, resulting in a scar.

Bacterial infections of the skin and tissues under the skin are more likely because the worms block the lymphatic vessels which makes the immune system Overview of the Immune System The immune system is designed to defend the body against foreign or dangerous invaders. Such invaders include Microorganisms (commonly called germs, such as bacteria, viruses, and fungi) Parasites... read more less able to defend the skin and adjacent tissues from bacteria.

Often, symptoms resolve, then recur. They are more severe when people are exposed to the infection for the first time.

After many years of infection, the blocked lymph vessels widen. Most people have no symptoms. But in a few people, the widened lymph vessels cause swelling that gradually becomes permanent (chronic). The legs are affected most often, but the arms, breasts, and genitals may be also. This swelling (called lymphedema Lymphedema Lymphedema is the accumulation of lymph in tissues, resulting in swelling. When lymphatic vessels are injured or obstructed, lymph fluid cannot drain and accumulates in tissues, causing swelling... read more ) develops because

The swelling makes the skin spongy. Pressing on the skin leaves an indentation that does not disappear right away (called pitting). Chronic swelling may make the skin hard and thick (called elephantiasis). In men, the scrotum may swell.

Bacterial and fungal infections of the skin are common in people with lymphatic filariasis. These infections, along with the inflammation caused by the worms, can cause pain and discomfort. The infections also contribute to the development of elephantiasis of the legs and occasionally arms and sometimes massive swelling in the scrotum.

Some people have mild joint pain and blood in the urine.

Less commonly, the lungs are affected by microfilariae in the blood stream, resulting in a disorder called tropical pulmonary eosinophilia. People may have a low-grade fever, feel short of breath, cough, or wheeze. If the infection persists, scar tissue (fibrosis) may form in the lungs.

The brief early symptoms usually resolve on their own. Whether treatment prevents or lessens the long-term effects of infection is uncertain.

Typically, lymphatic filariasis is treated with diethylcarbamazine. This drug is taken by mouth for 1 or 12 days. It kills microfilariae and some adult worms.

Before treating people with diethylcarbamazine, doctors check them for loiasis Loiasis Loiasis is infection of tissues under the skin or under the clear outer membrane that covers the eye (conjunctiva) with the roundworm Loa loa. Itchy swellings may appear, mainly on the... read more and onchocerciasis Onchocerciasis Onchocerciasis is infection with the roundworm Onchocerca volvulus. It causes itching, a rash, sometimes with scarring, as well as eye symptoms that may lead to blindness. The infection... read more because diethylcarbamazine can have serious side effects in people with these infections.

The effects of chronic infection are treated.

Chronic swelling requires meticulous skin care. People must be careful not to damage the skin and to thoroughly clean any minor cuts and scrapes. Such care helps prevent bacterial infections. Swelling may be reduced by wrapping elastic bandages around the affected limb or by elevating the limb. If elephantiasis, including swelling in the scrotum, is severe, surgery may be done to improve drainage in the lymphatic system.

Bacterial skin infections are treated with antibiotics given by mouth. The antibiotics may slow or prevent progression to elephantiasis.

For lung-related problems, diethylcarbamazine, taken for 14 to 21 days, is effective. However, the infection recurs in about one fourth of people. For them, treatment must be repeated.