Lymphedema is the accumulation of lymph in tissues, resulting in swelling.
Lymphedema results when the lymphatic system cannot adequately drain lymph from the tissues, causing swelling. Lymphedema may be due to
Several inherited disorders may cause congenital lymphedema. These disorders differ according to the age at which swelling becomes obvious.
This disorder results from having so few lymphatic vessels that they cannot handle all the lymph. The problem almost always affects the legs. Rarely, it affects the arms. Women are much more likely than men to have congenital lymphedema.
Rarely, the swelling is obvious at birth, but usually, the lymphatic vessels can handle the small amount of lymph produced in an infant. More often, the swelling appears later in life, as the volume of lymph increases and overwhelms the small number of lymph vessels.
The swelling starts gradually in one or both legs. The first sign of lymphedema may be puffiness of the foot, making the shoe feel tight at the end of the day. The shoe may leave indentations in the skin of the foot. (Many people who do not have lymphedema experience swelling after they stand for prolonged periods. They may have indentations around their ankles after they wear ankle socks, but the indentations are much less deep than those of lymphedema, and the surrounding area is not puffy.)
In the early stages of congenital lymphedema, the swelling goes away when the leg is elevated. This disorder worsens with time: The swelling becomes more obvious and does not disappear completely, even after a night’s rest.
Acquired lymphedema is more common than congenital lymphedema. It typically occurs after major surgical treatment, especially after cancer treatment in which lymph nodes and lymphatic vessels are removed or treated with radiation therapy. For example, the arm tends to swell after removal of a cancerous breast and lymph nodes in the armpit. Scarring of lymphatic vessels as a result of repeated infection also may cause lymphedema, but this type of scarring is very uncommon except among people who have an infection due to the tropical parasite Filaria (filariasis).
In acquired lymphedema, the skin looks healthy but is puffy or swollen. Pressing the area with a finger does not leave a significant indentation, as it does when edema results from inadequate blood flow in the veins. Rarely, especially in filariasis, the swollen limb becomes extremely large and the skin is so thick and ridged that it looks almost like elephant skin. This disorder is called elephantiasis.
Usually lymphedema can be diagnosed based on the person's symptoms. Sometimes an imaging test such as ultrasound, computed tomography (CT), or magnetic resonance imaging (MRI) is needed to determine the location of a blockage. In areas where filariasis is prevalent, tests for the parasite may be needed.
Lymphedema has no cure. For people with mild lymphedema, compression stockings applied to the legs or sleeves applied to the arms can reduce the swelling. People who are more severely affected may wear intermittent pneumatic compression stockings every day for several hours, depending on the extent of symptoms, to reduce the swelling. Once the swelling has been reduced, the person must wear graduated elastic stockings up to the knee or thigh every day from the moment of rising until bedtime. These stockings apply pressure at the ankle and less pressure farther up the leg. This measure controls the swelling to some degree. For lymphedema in the arm, pneumatic sleeves—like pneumatic stockings—can be used every day to reduce the swelling. Elastic sleeves are also available.
For elephantiasis, an extensive operation may be done to remove most of the swollen tissues under the skin.