3. You may have kidney disease.
One of the main functions of our kidneys is getting rid of the extra fluid in our body. When the kidneys cannot fulfill this function, extra fluid and sodium stagnate in the body and cause swelling.
This condition may be caused by urinary infections that do damage to the drainage system of the kidneys (for example, pyelonephritis). Edema caused by kidney failure usually occurs in the legs and around the eyes.