Causes
Lymphedema is a chronic, progressive, condition in which excessive fluid and protein accumulate in the interstitium, the space between cells. The condition occurs from impairment of the lymphatic system’s ability to drain fluids and proteins from the spaces in between cells and transport this fluid, known as lymph, back to the circulatory system. Lymphedema is classified as either primary or secondary.
Primary Lymphedema
Primary lymphedema is caused by congenital malformations (abnormal genetic conditions) of the lymphatic system and can be hereditary. These forms of primary lymphedema are classified according to ‘age of onset’:
- Congenital lymphedema (present at birth)
- Lymphedema praecox (before age 35)
- Lymphedema tardum (after age 35)
Although primary lymphedema has largely been attributed to genetic causes, the majority of primary lymphedema cases are not associated with the genes that have been identified to cause it. Therefore, it is important to note, that lymphedema is also classified as primary when it is idiopathic, or no known cause for the condition can be identified.
Secondary Lymphedema
Secondary is an acquired condition, with a known insult or disruption to the lymphatic system such as:
- Side effects of cancer treatments (excision of lymph nodes and/or radiation therapy)
- Benign or malignant tumor growth
- Trauma
- Surgery
- Infection
- Obesity
- Chronic venous insufficiency
- Iatrogenic causes
- Filariasis (parasitic)
