causes of edema
1 Excess fluid that accumulates in the abdominal cavity is called ascites. 2  Edema of unknown cause (idiopathic edema) occurs primarily in women.  Varicose veins or thrombophlebitis (a blood clot in an inflamed vein) of the deep veins in the legs causes edema that is localized to the legs.
Edema definition and facts. 1  Edema is a swelling, usually of the legs, feet, and/or hands due to the accumulation of excessive fluid in the tissues.  The edema that occurs in diseases of the heart, liver, and kidneys is mainly caused by salt retention, which holds the excess fluid in the body.