Lymphedema is an abnormal accumulation of protein rich fluid in the interstitium which causes chronic inflammation and reactive fibrosis of the affected tissues.

WHAT IS LYMPHEDEMA?

Lymphedema is a swelling of a body part, most often the extremities. It can also occur in the face, neck abdomen or genitals. Lymphedema is the result of the abnormal accumulation of protein rich edema fluid in the affected area. Its seriousness and the problems it creates are poorly understood in the medical community. Lymphedema is classified as either primary or secondary. Primary Lymphedema is the result of lymphatic dysphasia. It may be present at birth, but it more often develops later in life without obvious cause. Secondary Lymphedema is much more common, and is the result of surgery or the side effect of radiation therapy for cancer. Secondary forms may also occur after injury, scarring, trauma or infection of the lymphatic system. Lymphedema has important pathological and clinical consequences. In stage one Lymphedema, the swelling consists of protein rich fluid and may become temporarily reduced by simple elevation of the limb. If it remains untreated, however, the lymphedema causes a progressive hardening of the affected tissues, the result of a proliferation of connective tissue, adipose tissue and scarring which is characterized by a tremendous increase in volume, hardening of the dermal tissues, hyperkeratosis and papillomas of the skin. Infections such as cellulites, erysipelas or lymphangitis frequently develops in those suffering from lymphedema. Infections are most common in stage two and three lymphedema, each infection resulting in a worsening of the condition necessitating frequent hospitalizations.

Lymphedema treatments offered in the United States are: surgery, medications, pneumatic compression pump therapy, Manual Lymph Drainage (MDL), and Complete Decongestive Therapy (CDT).

 PRIMARY LYMPHEDEMA:

Primary lymphedema is characterized by an accumulation of protein rich fluid in the interstitium due to a low volume (mechanical) insufficiency of the lymphatic system. Approximate numbers only can be obtained to quantify the frequency of occurrence in the general population. The best estimates obtained thus far would indicate that around 1% of the US population has varying degrees of primary lymphedema. This number is supported in other countries where another potential cause, filarial infections, is not considered to be a factor.

SECONDARY LYMPHEDEMA:

Although there are many causes of secondary lymphedema the most common cause worldwide is an infection known as filariasis. This form is caused by a mosquito born parasite (Filaria) which resides in some tropical regions of the world. For the purposes of teaching MLD/CDT in non-tropical areas, most therapists will never encounter a filarial lymphedema in their practices unless they treat a population whom have traveled frequently to these areas. Should one encounter such a patient, however, the treatment is not considerably different and can be addressed with the techniques of MLD/CDT with a favorable outcome.

Secondary lymphedema means that there is a known cause for the presence of lymphedema in a body-part. Conversely, in primary forms of lymphedema, prior to the administration of diagnostic testing procedures, the clinician concludes that there is an unknown cause for the swelling. Only after diagnostic angiography, (lymphangiogram, lymphangioscintigaphy) is it revealed that a developmental defect is responsible.

In the non-tropical regions of the world the most common cause for the occurrence of lymphedema is cancer therapy. Treatments for many forms of cancer require lymph nodes sampling at the least and or full dissection of regional lymph nodes for staging of the disease as well as for the eradication of tumor sites. This disruption in the lymphatic system causes abnormal lymph drainage to the once present nodal areas resulting in poor uptake of lymph fluids as far back as the capillary beds. Other cancer treatment procedures can further disrupt normal drainage of lymphatic tissues such as radiation therapy. Radiation therapy can have a traumatic effect of the delicate lymphatic vessels which reside in the cutaneous and subcutaneous tissues. Furthermore, reconstructive surgical procedures can reduce the avenues for collateral vessel formation which are available in the intact superficial vessel network. The combined affect from the trauma of these cancer treatments is a decrease in the transport capacity of the lymphatic system which overtime may result in lymphedema.

Other causes of secondary lymphedema would include any significant trauma to lymph nodes or lymph vessels from accidental or self-induced causes, infections episodes such as cellulites and erysipelas, or surgical procedures to the cardiovascular system as in coronary bypasses which may remove or damage vessels running adjacent to veins in the legs. Additionally, malignant tumor blockage of the veins and lymphatic vessels constitutes a physical obstruction to normal blood and lymph drainage and will result in uncontrolled swelling.