What is Lymphedema?
Lymphedema is swelling in one or more extremities that results from impaired flow of the lymphatic system.
When the lymph vessels are blocked or unable to carry lymph fluid away from the tissues, localized swelling is the result, this is called Lymphedema. Lymphedema most often affects a single arm or leg, but in uncommon situations both limbs are affected.
Primary lymphedema is the result of an abnormality of the lymph vessels. This is a rare and usually inherited condition.
Secondary lymphedema results from damage to or obstruction of normally-functioning lymph vessels and nodes. This is a more common form of lymphedema and can be a result of surgery to remove lymph nodes.
It is estimated that close to 250 million people in the US may be affected by lymphedema.
What Causes Lymphedema?
Primary Lymphedema Causes
Primary lymphedema is an abnormality of the lymphatic system. This abnormality is generally present at birth, although symptoms may not become apparent until later in life. Depending upon the age at which symptoms develop, three forms of primary lymphedema have been described. Most primary lymphedema occurs without any known family history of the condition.
Secondary lymphedema causes
Secondary lymphedema develops when a normally-functioning lymphatic system is blocked or damaged.
What are the Symptoms of Lymphedema?
The swelling of lymphedema usually occurs in one or both arms or legs, depending upon the extent and localization of damage. Primary lymphedema can occur on one or both sides of the body as well. Lymphedema may be only mildly apparent or debilitating and severe, as in the case of lymphatic filariasis (see above), in which an extremity may swell to several times its normal size. It may first be noticed by the affected individual as an asymmetry between both arms or legs or difficulty fitting into clothing. If the swelling becomes pronounced, fatigue due to added weight may occur, along with embarrassment and restriction of daily activities.
The long-term accumulation of fluid and proteins in the tissues leads to inflammation and eventual scarring of tissues, leading to a firm, taut swelling that does not retain its displacement when indented with a fingertip (nonpittingedema). The skin in the affected area thickens and may take on a lumpy appearance described as an orange-peel (peau d'orange) effect. The overlying skin can also become scaly and cracked, and secondary bacterial or fungal infections of the skin may develop. Affected areas may feel tender and sore, and loss of mobility or flexibility can occur.
The immune system function is also suppressed in the scarred and swollen areas affected by lymphedema, leading to frequent infections and even a malignant tumor of lymph vessels known as lymphangiosarcoma.
How is Lymphedema Diagnosed?
A thorough medical history and physical examination are preformed to rule out other causes of limb swelling, such as edema due to heart disease, kidney failure, blood clots, or other health conditions. Often, the medical history of surgery or other conditions involving the lymph nodes will point to the cause and establish the diagnosis of lymphedema.
If the cause of swelling is not clear, other tests may be carried out to help determine the cause of limb swelling.
CT or MRI scans may be useful to identify tumors or other abnormalities in the lymphatic system.
Lymphoscintigraphy is a test that involves injecting a dye into lymph vessels and then observing the flow of fluid using imaging technologies. It can illustrate blockages in lymph flow.
Ultrasound is a test that uses sound waves and may be useful to evaluate blood flow. A blood clot in the veins may be a cause of limb swelling.
What are Possible Treatments for Lymphedema?
There is no cure for lymphedema. Treatments are designed to reduce the swelling and control discomfort and other symptoms.
Compression treatments can help reduce swelling and prevent scarring and other complications.
Surgical treatments for lymphedema are used to remove excess fluid and tissue in severe cases, but no surgical treatment is able to cure lymphedema.
Infections of skin and tissues associated with lymphedema must be promptly and effectively treated with appropriate antibiotics to avoid spread to the bloodstream. Patients affected by lymphedema must constantly monitor for infection of the affected area.
Examples of compression treatments are:
Can Lymphedema be Prevented?
Primary lymphedema cannot be prevented, but measures can be taken to reduce the risk of developing lymphedema if one is at risk for secondary lymphedema, such as after cancer surgery or radiation treatment.
The following steps may help reduce the risk of developing lymphedema in those who are at risk for developing secondary lymphedema:
- Keep the affected arm or leg elevated above the level of the heart, when possible.
- Avoid tight or constricting garments or jewelry (also avoid the use of blood pressure cuffs on an affected arm).
- Do not apply a heating pad to the affected area or use hot tubs, steam baths, etc.
- Keep the body adequately hydrated.
- Avoid heavy lifting and forceful activity with the affected limb; but normal, light activity is encouraged.
- Do not carry a heavy purse on an affected arm.
- Practice thorough and careful skin hygiene.
- Avoid insect bites and sunburns whenever possible. Use insect repellent and sunscreen to prevent insect bites and sunburns.
References
Revs Jr., Don R., et al. "Lymphedema." Medscape. 11 Oct. 2011
NCI, PDQ® Lymphedema: http://www.cancer.gov/cancertopics/pdq/supportivecare/lymphedema/Patient/page1