Lymphedema is the build-up of lymph fluid in an area of the body. The lymph fluid normally flows through a system of canals between lymph nodes and is eventually returned to the blood stream. The fluid carries infection and foreign material away from the skin and tissue. A disruption in this normal flow results in lymphedema and abnormal swelling. The disruption can be caused by surgery, cancer, certain infections and radiation therapy. Individuals with lymphedema are at a greater risk of developing infection in the affected body part.