What is it?
This is a syndrome of clotting (thrombosis), recurrent miscarriages and low platelets, which is associated with certain blood proteins called antiphospholipid antibodies. Some refer to it as “sticky blood” although this is technically incorrect.
What are antiphospholipid antibodies?
Antibodies are usually produced by the body to fight infection. Antiphospholipid antibodies are autoantibodies, which means that they are antibodies which are directed against one’s self. These antibodies react with phospholipid, a type of fat molecule that is part of the normal cell membrane. Blood tests are used to identify these antibodies. The two main antibodies that your doctor would check for are the anticardiolipin antibody, beta 2 glycoprotein 1 and the lupus anticoagulant.
What are the main features of antiphospholipid syndrome?
The most dramatic sign that the disease is present is thrombosis or clot, for example, deep vein thrombosis (DVT) in the leg or arm. This may be happen just once or be recurrent, or become worse by a clot traveling to the lung (pulmonary embolus). Blood clots may also occur in internal veins of organs like the liver and kidney and so on. Arteries can also clot and for reasons not completely understood, the arteries of the brain appear particularly sensitive to the clotting effects of antiphospholipid antibodies and this can present as a stroke. This tendency for clotting may happen quickly like a DVT or chronically for example with a history of headaches or memory loss going back many years. As mentioned, recurrent miscarriages are a feature of this syndrome, usually occurring later in pregnancy. In a small percentage of patients, platelet numbers are affected and rarely, platelet counts may fall to very low numbers.
Why do recurrent miscarriages occur?
The blood supply to the foetus in the womb is complicated and delicate. In pregnancy, the physiology of the body changes significantly and one of these changes is a slight increase in the blood viscosity (“stickiness”). In some women with antiphospholipid antibodies, clotting occurs in the placenta, leading in a cut off in blood supply to the placenta and the foetus. The result is miscarriage or foetal loss.
In general, treatment consists of “thinning” the blood. Not all patients need to be treated. If a person has the lupus anticoagulant or anticardiolipin antibody, but has never had a thrombosis, treatment is not currently recommended. If a person has had a thrombosis, treatment may then depend on which blood vessel was affected.
The three most commonly used drugs are aspirin, warfarin and heparin. Aspirin and warfarin are both taken orally while heparin, which is administered by injection, is less widely used. Your doctor will discuss with you which medication would be best in your situation if you require treatment. Patients who have had many miscarriages and have a positive blood test will need to take heparin and / or aspirin during pregnancy.
Subcutaneous injections of heparin and low dose aspirin are the standard therapy for preventing new miscarriages
How successful is the treatment?
In general, treatment appears to be successful overall. The length of time that this treatment is necessary is not always clear, although if the person has had a major thrombosis, for example a stroke, the treatment is lifelong. Many physicians do recommend long–term or lifelong treatment to prevent future episodes of thrombosis.
This is one of a set of articles by Dr. Humeira Badsha, Specialist Rheumatologist, for patient awareness.