What is pitting edema?
If you depress the skin of a swollen area (e.g., leg) with a finger and the pressing causes an indentation in the skin that persists for some time after the release of the pressure, it is pitting edema. Any form of pressure, such as from the elastic part of socks, can induce the pitting of this edema. Pitting edema is caused by either systemic diseases, that is, diseases that affect the various organ systems of the body, or by local conditions involving just the affected extremities. The most common systemic diseases that are associated with pitting edema involve the heart, liver, and kidneys. In these diseases, edema occurs primarily because of the body’s retention of too much salt (the chemical compound sodium chloride). The excess salt holds excess water in the interstitial tissue spaces (edema). Idiopathic (of unknown cause) edema, also sometimes called cyclical edema, occurs most often in women and just prior to each menstrual period. The most common local conditions that cause ed