Fluid retention around the ankles often involves the rest of the body, too. A blood clot in the veins may cause pooling of fluid in the lower limbs, while swelling of the ankles may be accompanied by difficulty in breathing and the inability to lie flat on the bed in heart failure 2. Low levels of a protein called albumin due to a damaged liver or from kidney failure can cause generalized swelling, too. Pregnancy, certain drugs and other conditions may also result in ankle swelling.

Venous Insufficiency

Bluish discoloration of the skin in the affected lower limb is usually observed when there is limited blood flow to the veins in this area. Fluid accumulates in the lower limbs when a blood clot or local swelling from a nearby infection prevents the flow of fluid from the veins and lymphatic vessels that normally drain fluid from the legs. Swelling around the ankles may also occur after the surgical removal of lymph nodes for cancer treatment.

Heart Failure

According to a 2013 report by the American Heart Association in “Circulation,” heart failure can result in early death in about half of those who are diagnosed with this condition. Because of the damaged heart’s inability to effectively pump blood for delivery to the rest of the body, blood backs up in the veins, and fluid eventually seeps out into the tissues of the surrounding major body organs. As a result, many people with severe heart failure often complain of difficulty in breathing even at rest and the inability to lie flat and sleep without pillows, in addition to ankle swelling.

Kidney Failure

Because patients with severe kidney failure are unable to remove the excess fluid and toxins in the body, they often have high blood pressure and evidence of fluid accumulation in the lungs. A dialysis machine removes excess fluid and relieves some of these symptoms.

Low Blood Protein

The body keeps blood fluid from seeping out into the tissues using blood proteins as "fluid magnets." Repeated urinary tract infections, uncontrolled diabetes and allergic reactions can result in kidney damage and the loss of proteins in the urine -- and without these proteins fluid seeps out, leading to swelling all over. Pooling of fluid is also often seen in areas more prone to the effects of gravity -- such as ankles, if standing up -- in late-stage liver failure. The prolonged intake of a protein-deficient diet also results in generalized swelling along with the development of a specific type of heart disease.

Other Causes

Swelling around the ankles is also seen in pregnancy, with the intake of certain drugs -- such as estrogens, vasodilators, nifedipine -- and abnormal thyroid hormone levels.

Warnings

If ankle swelling is accompanied by urgent symptoms such as difficulty breathing, blood-clotting abnormalities or altered consciousness and behavior -- drowsiness, difficulty maintaining wakefulness -- see a doctor right away, since these symptoms may indicate a medical emergency.