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antiphospholipid antibody syndrome





Contents
  • What causes APS?
  • Who is at risk?
  • Signs and symptoms
  • Diagnosis
  • Treatment
  • Living with APS
  • Antiphospholipid antibody syndrome (APS) is an autoimmune disorder. Autoimmune disorders occur when the immune system makes antibodies that attack and damage the body's tissues or cells by mistake. Antibodies are a type of protein that the immune system usually makes to defend against infection.

    In APS, the body mistakenly makes antibodies that attack phospholipids – a type of fat. Phospholipids are found in all living cells and cell membranes, including blood cells and the lining of blood vessels.

    When antibodies attack phospholipids, they damage cells. This causes unwanted blood clots to form in the arteries and veins.

    Usually, blood clotting is a normal bodily process. Blood clots help seal small cuts or breaks and prevent you from losing too much blood. In APS, however, too much blood clotting can block blood flow and damage the body's organs.


    Overview

    Some people have APS antibodies, but don't ever have signs or symptoms of the disorder. The presence of APS antibodies, by itself, doesn't mean that you have APS. To be diagnosed with APS, you must have APS antibodies and a history of health problems related to the disorder.

    APS can lead to a number of health problems, such as stroke, heart attack, kidney damage, deep vein thrombosis, pulmonary embolism, or pregnancy-related problems.

    Pregnancy-related problems may include multiple miscarriages, a miscarriage late in pregnancy, or a premature birth due to eclampsia. (Eclampsia, which follows preeclampsia, is a serious condition that causes seizures in pregnant women.)

    Very rarely, some people who have APS develop many blood clots within weeks or months. This condition is called catastrophic antiphospholipid syndrome (CAPS).

    People who have APS also are at higher risk for thrombocytopenia. This is a condition in which your blood has a low number of blood cells called platelets. This can lead to mild to serious bleeding.


    In APS, thrombocytopenia occurs because the platelets are used up by the clotting process or because antibodies destroy them.

    In some cases, APS can be fatal. This may occur due to large blood clots or blood clots in the heart, lungs, or brain.


    Outlook

    APS can affect people of any age. However, it's more common in women and people who have other autoimmune or rheumatic disorders, such as lupus. ("Rheumatic" refers to disorders that affect the joints, bones, or muscles.)

    APS has no cure, but medicines can help prevent its complications. Medicines are used to stop blood clots from forming and keep existing clots from getting larger. Treatment for the disorder is long term.

    If you have APS and another autoimmune disorder, it's important to control that condition as well. When the other condition is controlled, APS may cause fewer problems.





    What causes antiphospholipid antibody syndrome?

    What causes the immune system to make antibodies against phospholipids isn't known. APS causes unwanted blood clots to form in the body's arteries and veins. Usually, blood clotting is a normal bodily process. It helps seal small cuts or breaks and prevents you from losing too much blood. In APS, however, too much blood clotting can block blood flow and damage the body's organs.

    Researchers don't know why APS occurs. Some believe that the antibodies damage or affect the inner lining of the blood vessels, causing blood clots to form. Others believe that the immune system makes antibodies in response to blood clots damaging the blood vessels.


    Who is at risk?

    Antiphospholipid antibody syndrome (APS) can affect people of any age. The disorder is more common in women than men, but it affects both sexes.

    APS also is more common in people who have other autoimmune or rheumatic disorders, such as lupus. About 10 percent of all people who have lupus also have APS. About half of all people who have APS also have another autoimmune or rheumatic disorder.


    Signs and symptoms of APS

    The signs and symptoms of antiphospholipid antibody syndrome (APS) are related to abnormal blood clotting. The outcome of a blood clot depends on its size and location. Blood clots can form in or travel to the arteries or veins in the brain, heart, kidneys, lungs, and limbs. Clots can limit or block blood flow. This can damage the body's organs and may cause death.


    Major signs and symptoms

    Major signs and symptoms of blood clots include:
    • Chest pain and shortness of breath
    • Pain, redness, warmth, and swelling in the limbs
    • Ongoing headaches
    • Speech changes
    • Upper body discomfort in the arms, back, neck, and jaw
    • Nausea (feeling sick to your stomach)
    Blood clots can lead to stroke, heart attack, kidney damage, pulmonary embolism, and deep vein thrombosis.

    Pregnant women who have APS can have successful pregnancies. However, they're at higher risk for miscarriages, stillbirths, and other pregnancy-related problems, such as preeclampsia.

    Preeclampsia is high blood pressure that occurs during pregnancy. This condition may progress to eclampsia. Eclampsia is a serious condition that causes seizures in pregnant women.

    Some people who have APS also have thrombocytopenia. This is a condition in which your blood has a low number of blood cells called platelets. Mild to serious bleeding causes the main signs and symptoms of thrombocytopenia. Bleeding can occur inside the body (internal bleeding) or on the skin.

    Other signs and symptoms

    Other symptoms of APS include chronic headaches, memory loss, or heart valve disease. Some people who have the disorder also get a lacy-looking red rash on their wrists and knees.


    Diagnosis

    Your doctor will diagnose antiphospholipid antibody syndrome (APS) based on your medical history and the results from blood tests.


    Specialists involved

    People who have APS often are treated by a hematologist (a blood disease specialist). You may have APS and another autoimmune disorder, such as lupus. If so, you also may be treated by a doctor who specializes in that disorder.

    Many autoimmune disorders that occur with APS also affect the joints, bones, or muscles. Rheumatologists specialize in treating these types of disorders.


    Medical history

    Some people have APS antibodies, but don't ever have signs or symptoms of the disorder. The presence of APS antibodies, by itself, doesn't mean that you have APS.

    To be diagnosed with APS, you must have APS antibodies and a history of health problems related to the disorder. These health problems may include stroke, heart attack, kidney damage, deep vein thrombosis, pulmonary embolism, or pregnancy-related problems.

    Pregnancy-related problems may include multiple miscarriages, a miscarriage late in pregnancy, or a premature birth due to eclampsia. (Eclampsia, which follows preeclampsia, is a serious condition that causes seizures in pregnant women.)


    Blood tests

    Your doctor can use blood tests to confirm a diagnosis of APS. These tests check your blood for any of the three APS antibodies: anticardiolipin, B2 glycoprotein I, and lupus anticoagulant.

    The term "anticoagulant" refers to a substance that prevents blood clotting. It may seem odd that one of the APS antibodies is called lupus anticoagulant. This is because the antibody slows clotting in lab tests. However, in the human body, it increases the risk for blood clots.

    To test for the APS antibodies, a small amount of blood is taken from your body. It's often drawn from a vein in your arm using a small needle. The procedure usually is quick and easy, but it may cause some short-term discomfort, such as a slight bruise.

    You may need a second blood test to confirm positive results. This is because a single positive test can result from a short-term infection. The second blood test often is done 12 weeks or more after the first one.

    Some healthy people may test positive for APS antibodies but have no signs or symptoms of the disorder. The presence of the APS antibodies, by itself, doesn't mean that you have APS.


    Treatment

    Antiphospholipid antibody syndrome (APS) has no cure, but some medicines can help prevent complications. The goals of treatment are to prevent blood clots from forming and keep existing clots from getting larger.

    If you have APS and another autoimmune disorder, such as lupus, it's important to control that condition as well. When the other condition is controlled, APS may cause fewer problems.

    Research is ongoing for new ways to treat APS.


    Medicines

    Anticoagulants, or "blood thinners," are used to stop blood clots from forming. They also keep existing blood clots from getting larger. These medicines are taken as either a pill, an injection under the skin, or through a needle or tube inserted into a vein (called intravenous, or IV, injection).

    Warfarin and heparin are two blood thinners used to treat people who have APS. Warfarin is given in pill form. (Coumadin® is a common brand name for warfarin.) Heparin is given as an injection or through an IV tube. There are different types of heparin. Your doctor will discuss the options with you.

    Your doctor may treat you with both heparin and warfarin at the same time. Heparin acts quickly. Warfarin takes 2 to 3 days before it starts to work. Once the warfarin starts to work, the heparin is stopped.

    Sometimes aspirin is used with warfarin. In other cases, aspirin may be used alone. Aspirin also thins the blood and helps prevent blood clots.

    Blood thinners don't prevent or treat APS. They simply reduce the risk of further blood clotting. Treatment with these medicines is long term. Discuss all treatment options with your doctor.


    Side effects

    The most common side effect of blood thinners is bleeding. This happens if the medicine thins your blood too much. This side effect can be life threatening.

    Sometimes the bleeding is internal (inside your body). People treated with blood thinners usually need regular blood tests, called PT and PTT tests, to check how well their blood is clotting.

    These tests also show whether you're taking the right amount of medicine. Your doctor will check to make sure that you're taking enough medicine to prevent clots, but not so much that it causes bleeding.

    Talk to your doctor about the warning signs of internal bleeding and when to seek emergency care.


    Treatment during pregnancy

    Pregnant women who have APS can have successful pregnancies. With proper treatment, women who have APS are more likely to carry their babies to term.

    Pregnant women who have APS usually are treated with heparin or heparin and low-dose aspirin.

    Babies whose mothers have APS are at higher risk for slowed growth while in the womb. If you're pregnant and have APS, you may need to have extra ultrasound tests (sonograms) to check the fetus' growth. This test uses sound waves to look at organs and structures inside your body.


    Treatment for other medical conditions

    People who have APS are at increased risk for thrombocytopenia. This is a condition in which your blood has a low number of blood cells called platelets. Platelets help the blood clot. If you have APS, you will need regular complete blood counts (a type of blood test) to count the number of platelets in your blood.

    Thrombocytopenia is treated with medicines and medical procedures.

    If you have other health problems, such as heart disease or diabetes, work with your doctor to manage them.


    Living with aplastic anemia

    Antiphospholipid antibody syndrome (APS) has no cure. However, you can take steps to control the disorder and prevent complications.

    Take all medicines as your doctor prescribes, get ongoing medical care, and talk to your doctor about healthy lifestyle changes and other concerns.


    Medicines

    You may need to take anticoagulants, or "blood thinners," to prevent blood clots or to keep them from getting larger. You should take these medicines exactly as your doctor prescribes.

    Tell your doctor about all other medicines you're taking, including over-the-counter or herbal medicines. Some medicines, including over-the-counter ibuprofen or aspirin, can thin your blood. Taking two medicines that thin your blood may increase your risk for bleeding.


    Ongoing medical care

    If you have APS, it's important to get regular medical checkups. Have blood tests done as your doctor directs. These tests help track how well your blood is clotting.

    The medicines used to treat APS may cause bleeding. Bleeding can occur inside your body (internal bleeding) or on its surface. Know the warning signs of internal bleeding, so you can get help right away. They include:
    • Unexplained bleeding from the gums and nose
    • Increased menstrual flow
    • Bright red vomit or vomit that looks like coffee grounds
    • Bright red blood in your stools or black, tarry stools
    • Pain in your abdomen or severe pain in your head
    • Sudden changes in vision
    • Sudden loss of movement in your limbs
    • Memory loss or confusion
    A lot of bleeding after a fall or injury or easy bruising or bleeding also may mean that your blood is too thin. Talk to your doctor about these warning signs and when to seek emergency care.


    Lifestyle changes

    Talk to your doctor about lifestyle changes that can help you stay healthy. Ask him or her whether your diet may interfere with your medicines. Some foods or drinks may increase or decrease the effects of warfarin.

    Discuss with your doctor what amount of alcohol is safe for you to drink if you're taking medicine. If you smoke, ask your doctor about programs and products that can help you quit. Smoking can damage your blood vessels and raise your risk for a number of health problems.

    APS medicines may increase your risk for bleeding. Thus, your doctor may advise you to avoid activities that have a high risk of injury, such as some contact sports.


    Other concerns


    Pregnancy

    APS can raise your risk for a number of pregnancy-related problems. Talk to your doctor about how to manage your APS if your pregnant or planning a pregnancy.

    With proper treatment, women who have APS are more likely to carry babies to term than women whose APS isn't treated.


    Birth control

    Women who have APS shouldn't use birth control or hormone therapy that contains estrogen. Estrogen increases the risk for blood clots. Talk to your doctor about other birth control methods.


    Surgery

    If you need surgery, your doctor may adjust the amount of medicines you take before, during, and after the surgery to prevent dangerous bleeding.


    Related category

       • HEALTH AND DISEASE

    Source: U.S. National Heart, Lung and Blood Institute