According to WebMD, swollen feet are caused by a variety of factors that include pregnancy, injuries such as sprained ankles and lymph fluid retention. While swollen feet during pregnancy is considered common, rapid swelling can indicate preeclampsia, a condition that causes severe high blood pressure. Lymph fluid retention is a common but serious complication following radiation treatments or lymph node removal.
Mayo Clinic explains that fluid retention in the feet and ankles can also indicate congestive heart failure or leg vein blockages. It is imperative for individuals experiencing symptoms of swollen feet or ankles to consult with a physician as soon as possible if the swelling is accompanied by breathing difficulties or chest discomfort, or if the swollen areas become pitted or dimpled when the skin is pressed.
Healthline explains that swollen feet can also indicate kidney failure, a life-threatening condition in which the kidneys fail to filter out toxins from the blood. Medical conditions such as heart disease, cirrhosis of the liver, cancer and blood clotting disorders can put individuals at risk for kidney failure. Additional symptoms of the condition include decreased urine output, tiredness, disorientation and chest pain. Treatments for kidney failure include kidney transplant or dialysis, a procedure in which kidney function is assisted by a medical machine.