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> > > > > What are the symptoms of antiphospholipid syndrome (APS)?

What are the symptoms of antiphospholipid syndrome (APS)?

The two main problems caused by antiphospholipid syndrome (APS) are blood clotting (thrombosis) and pregnancy problems, particularly recurrent miscarriage.

Blood clotting can occur in:

  • the veins, causing pain and swelling, typically in your calf (deep vein thrombosis or DVT) – this can sometimes lead to pulmonary embolism if a piece of the clot breaks away and travels to your lung
  • the arteries, causing high blood-pressure or strokes
  • the brain, which can cause memory loss, migraines, forgetfulness, slurred speech, fits or sight problems.

In pregnancy, APS can cause recurrent miscarriage. This can happen at any time during your pregnancy but is most common between 3 and 6 months. APS can also cause other pregnancy problems, such as high blood pressure (pre-eclampsia), small babies and early deliveries. APS is now recognised as one of the most important treatable causes of recurrent miscarriages.

Other problems sometimes associated with APS include:

  • Heart problems – The heart valves may thicken and fail to work, or your arteries may narrow because their walls get thicker, leading to angina.
  • Kidney problems – APS can cause narrowing of the blood vessels, resulting in high blood pressure.
  • Infertility – Testing for antiphospholipid antibodies (aPL) is becoming routine in infertility clinics.
  • Skin problems – Some people develop a blotchy rash, often seen on the knees or arms and wrists, with a lacy pattern (known as livedo reticularis).
  • Low platelet count – Some people with APS have very low platelet levels – often there are no symptoms, although people with very low counts may bruise easily or experience strange or excessive bleeding.

Very rarely, APS can cause clots to develop in small blood vessels in several parts of your body at once, causing damage to several organs at the same time and making you seriously ill. This is called catastrophic APS and is very rare. It’s thought to be triggered by things like infection, trauma, medication or surgery. You should have quick and easy access to your rheumatology or haematology team in these circumstances.


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