What are the causes of Lymphedema?

The cause of lymphedema is fundamentally unknown, but there are identifiable circumstances associated with the onset of the condition. Primary [inborn] lymphedema can be present at birth (congenital), can occur during adolescence (Milroy's), or can occur after age 35. Secondary [acquired] Lymphedema can triggered in an otherwise lymphedema-free person by surgery/radiation therapy for cancer, a traumatic injury, or an infection. Secondary lymphedema is far more common than primary.

In equatorial regions of the earth, most cases of lymphedema result from infection associated with parasites. In Europe, the U.S.A., and other areas, acquired lymphedema is commonly associated with complications following treatment for cancers. Other causes of secondary lymphedema include trauma, tuberculosis, and iatrogenic injury; subcutaneous injections of drugs (such as pentazocine) may also injure the lymphatics and induce this disorder. Lymphedema may be a temporary condition, or it may be chronic. Chronic lymphedema is seen more commonly in cancer patients.