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What is Antiphospholipid Syndrome?

Antiphospholipid syndrome (APS) is a rare autoimmune disorder defined by recurring blood clots (thromboses) that can block blood vessels (arteries and veins). Blood clots can develop in any blood vessel of the body, including in the legs, heart, lungs, and other organs, such as the spleen and kidneys. These clots can result in strokes, heart attack, pulmonary embolism (PE), or other life-threatening conditions. APS can also cause stillbirth and miscarriage during pregnancy. It is also of importance to know that some individuals who have APS do not have any signs or symptoms. There is no cure for this rare condition, but medications can decrease the possibility of blood clots and miscarriages.

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Causes of Antiphospholipid Syndrome

Antiphospholipid syndrome is defined by the presence of antiphospholipid antibodies in the body. Phospholipids are fat molecules that are involved in the proper functioning of cell membranes and are found throughout the body. Antibodies are specialized proteins produced by the body’s immune system to fight infection. In APS, antibodies mistakenly attack healthy tissue and certain proteins that bind to phospholipids, resulting in the formation of blood clots.
It is not clear what prompts the immune system to produce abnormal antibodies. As with other autoimmune conditions, environmental, hormonal, and genetic factors are believed to play a part. APS can be caused by an underlying condition, such as an autoimmune disorder or can also occur without an underlying cause.

Signs and Symptoms of Antiphospholipid Syndrome

The signs and symptoms of antiphospholipid syndrome are connected to the presence and location of blood clots in the specific blood vessel.

  • Blood clots in legs or deep vein thrombosis (DVT): Signs and symptoms of this include pain, swelling, and redness.
  • Pulmonary embolism (PE): A blood clot from the legs can break off, travel in the bloodstream, and become lodged in the lungs. This is called pulmonary embolism and can result in breathlessness, exhaustion, sudden pain in the chest, high blood pressure of the pulmonary arteries, or sudden death.
  • Blood clots in the brain: When blood clots affect blood flow to the brain several problems can occur including major complications such as stroke or stroke-like symptoms called transient ischemic attacks (TIA).
  • Repeated miscarriages or stillbirths: Other pregnancy related complications include premature delivery and preeclampsia (life-threatening high blood pressure condition).
  • Skin rashes and other skin diseases
  • Thrombocytopenia (low levels of blood platelets)
  • Valvular heart disease (clot-like deposits on the valves of the heart) which can permanently damage the valves

Diagnosis of Antiphospholipid Syndrome

If you have had occurrences of blood clots or loss of pregnancy that are not explained by known illnesses, your physician may order blood tests to look for clotting and for the presence of the antibodies connected to antiphospholipid syndrome. In order to confirm the diagnosis of APS, the antibodies should appear in your blood at least twice, in tests performed twelve or more weeks apart. You can also have antiphospholipid antibodies and yet never develop signs or symptoms. A diagnosis of APS is only made when these antibodies trigger health issues.

Treatment for Antiphospholipid Syndrome

People with antiphospholipid syndrome who do not exhibit symptoms may not need any treatment. Some people may receive prophylaxis (preventative) therapy to prevent the formation of blood clots. For many patients, daily treatment with aspirin (which thins the blood and prevents blood clots) may be all that is required.

People with a history of thrombosis may be treated with medications that prevent clotting by thinning the blood. These medications are commonly known as anticoagulants and may include warfarin (Coumadin) and heparin. New oral blood thinners such as apixaban, rivaroxaban, and dabigatran have recently been approved to treat other blood clotting disorders. Studies are required to ascertain whether these medications are suitable for preventing recurrent thromboses in patients with antiphospholipid syndrome. People with recurrent thrombotic episodes may need lifelong anticoagulant therapy.

Significantly, affected patients are strongly recommended to reduce or avoid risk factors that increase the risk of blood clot formation. Such risks include high blood pressure (hypertension), use of oral contraceptives, diabetes, or smoking. At the time of pregnancy, women with APS who are at a high risk for pregnancy loss are treated with heparin, sometimes in combination with low dose aspirin.

In some instances, heart valve damage due to APS may be severe and warrant surgical replacement of the valves.

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