Antiphospholipid Syndrome Symptoms and Treatment

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Antiphospholipid syndrome (APS), also known as 'sticky blood,' is an autoimmune disorder –the result of the immune system essentially turning on the body and attacking it in error. In the case of APS, the body makes antibodies to its own blood proteins.

Antiphospholipid syndrome can occur in individuals without any associated disease. This is called primary APS. The disorder may also occur with systemic lupus erythematosus (SLE) or another autoimmune disorder. This is called secondary APS.

How frequently antiphospholipid syndrome occurs is not yet known. APS antibodies can be found in as many as 50% of people with lupus and in about 1% to 5% of the rest of the population. Antiphospholipid syndrome most commonly occurs in young to middle-aged adults, but it can begin at any age.


Along with the antibodies, the body begins producing blood clots. The blood clots can block arteries and veins, cutting off blood supply to a part of the body. The symptoms of the individual experiences come from the location(s) and the effects of blood clots:

  • Veins or arteries of the arms or legs - Clots may cause pain, swelling, numbness, tingling in the hands or feet, or leg ulcers. If the blood supply was completely cut off to a part, such as a toe, the individual could lose the toe.
  • Arteries of the heart - Clots may cause chest pain or heart attack. The individual may also have a heart murmur or heart valve problems.
  • Blood vessels of the skin - Clots may cause bruises (purpura) or a blotchy, purplish rash called livedo reticularis.
  • Blood vessels of the brain - A clot that cuts off blood supply to a part of the brain causes a stroke. An individual with APS may also experience migraine headaches or seizures.
  • Placenta during pregnancy - Women with APS may have frequent miscarriages or premature births.

The most serious form of antiphospholipid syndrome, called catastrophic APS, occurs when many internal organs develop blood clots over a period of days to weeks.


Diagnosis of antiphospholipid syndrome relies on characteristic symptoms and signs, plus laboratory tests. If an individual has had blood clots in the legs without any other possible cause, for example, APS may be to blame. A blood test for anticardiolipin antibodies can help confirm the diagnosis. Other abnormal test results, such as decreased platelets or anemia, may be present. A computed tomography (CT) scan or magnetic resonance imaging (MRI) can confirm the presence of blood clots.


Treatment for antiphospholipid syndrome is based on the individual's symptoms. Catastrophic APS requires hospitalization. Some individuals who have characteristic antibodies but no symptoms of APS may be started on daily low-dose aspirin to help reduce the risk of blood clots forming. If a blood clot is discovered, the person is started on anticoagulant medication such as Coumadin (warfarin) or Lovenox (enoxaparin).

With medication and lifestyle modifications (such as avoiding long periods of inactivity in which clots can form in the legs), most people with primary antiphospholipid syndrome can lead normal, healthy lives. Those who have secondary APS may have additional problems due to their underlying rheumatic or autoimmune conditions.

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