Edema (American English), also spelled oedema (Commonwealth English), and also known as fluid retention, swelling, dropsy and hydropsy, is the build-up of fluid in the body's tissue. Most commonly, the legs or arms are affected. Symptoms may include skin that feels tight, the area feeling heavy, and joint stiffness. Other symptoms depend on the underlying cause.
Causes may include venous insufficiency, heart failure, kidney problems, low protein levels, liver problems, deep vein thrombosis, infections, kwashiorkor, angioedema, certain medications, and lymphedema. It may also occur in immobile patients (stroke, spinal cord injury, aging), or with temporary immobility such as prolonged sitting or standing, and during menstruation or pregnancy. The condition is more concerning if it starts suddenly, or pain or shortness of breath is present.