Antiphospholipid Syndrome (Also known as Lupus Anticoagulants or Hughes Syndrome)


What is antiphospholipid syndrome?

Are there any alternate names for APS?

What are the signs and symptoms of antiphospholipid syndrome?

When should I see a doctor?

How are you tested for antiphospholipid syndrome?

What causes APS?

What is the treatment for APS?

Can I do anything to prevent the development of antiphospholipid syndrome?

In Conclusion


Antiphospholipid Syndrome

As if receiving a diagnosis of lupus is not complicated and scary enough, being diagnosed with something called antiphospholipid (pronounced An-ti-fos-fo-LIP-id) syndrome (APS) can be even more scary and confusing. We hope this blog can shed some light on what antiphospholipid syndrome is, how it relates to systemic lupus erythematosus, as well as how it is diagnosed, treated and managed.

Simply put, antiphospholipid syndrome (APS) is an autoimmune disorder that is characterized by excessive clotting of blood in the arteries and veins.  Usually, blood clotting happens naturally as the body’s response to cuts and scrapes, and small breaks in blood vessels. In APS, a tendency for excessive clotting can constrict or even block blood flow and end up damaging internal organs.

Types of APS:

How it works:

  • All cells in your body have membranes made of phospholipids, a class of lipids (fatty acids), that hold the cell together. Within these phospholipids, antibodies play a role in how quickly or slowly blood clots. In APS, your body produces antiphospholipid antibodies that mistakenly attack your body’s own phospholipids.Antiphospholipid Syndrome
  • An antibody is a protein that is produced by the plasma (blood) cells An and used by the immune system. The antibodies seek out and target antigens (foreign objects such as viruses and bacteria). Some examples of antigens include: microorganisms like bacteria, fungi, parasites, viruses, and chemicals.
  • The purpose of these proteins (antibodies) within phospholipids is to control how quickly or slowly blood clots. As a result, a patient suffering with antiphospholipid syndrome or phospholipid antibody syndrome has an abnormally higher chance of blood clotting or narrowed blood vessels.

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Alternate names for APS:

To make things even more confusing, this syndrome often goes by several different names. Here are some of those names and explanations as to why they are used instead of APS:

  • Hughes syndrome: In honor of the doctor who first described it.
  • Lupus anticoagulant: Many people use this name, however, it is not actually the name of the syndrome, but rather describes the anticoagulants (the substances that prevent the clotting of blood) that are found in large quantities in those with APS. Lupus anticoagulant antibodies are a bit confusing, because despite their name (anticoagulant refers to a substance that prevents clotting), these antibodies actually promote abnormal clotting. These antibodies are a type of antiphospholipid antibody that attack the lipids (fats) in the lining of cells. Most often, lupus anticoagulants are found in people with diseases such as systemic lupus erythematosus (SLE), but can also occur if you take certain medications, or have conditions such as inflammatory bowel disease (Crohn’s disease or ulcerative colitis), certain infections or certain types of tumors. About 50% of people with SLE have these antibodies, however, they are also found in healthy people.
  • Phospholipid antibody syndrome (aPL antibodies): Less commonly used, Phospholipid antibody” syndrome rephrases the “antiphospholipid” part of antiphospholipid syndrome. Phospholipids are a class of lipids (molecules) and are a major component of all cell membranes.

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Signs and symptoms of antiphospholipid syndrome

  • Vascular Thrombosis: It may appear for the first time as a blood clot in an artery or vein (this is called a vascular thrombosis).
  • Embolism: It may appear as a blockage of a blood vessel that has been caused by a clot that has traveled in the blood stream from another location in the body ( this is called an embolism).
  • Pregnancy Complications: A woman who has recurring pregnancy loss may find out through testing that APS might be the underlying cause.Antiphospholipid Syndrome
  • Thrombocytopenia or (Immune Thrombocytopenia): This is a condition associated with APS that means that a person has low platelets. Platelets are little pieces of blood cells that help wounds heal and blood to clot. If you have a low platelet count, you can be at risk for mild to serious bleeding.
  • Rashes or skin conditions: Some people may develop a rash that can be described as red with a mottled or lacy, net-like pattern. This is called livedo reticularis.  Others may have ulcers or sores, most often on the legs, and others may have necrosis (a condition when the skin tissue dies).
  • Stroke or other neurological disorders: Embolic stroke (caused by a blood clot that travels to the brain) or cerebrovascular thrombosis (a blood clot that forms in the brain) can occur. Please see the signs regarding ‘when to see a doctor’ below. Seizures, migraines, other cognitive dysfunctions can also be indicators of those with aPL antibodies, although studies are still being done to prove the link between those conditions and the occurrence of APS strokes.
  • Lupus and other autoimmune disorders: Because APS is classified as an immune disorder (when the immune response attacks the body’s healthy tissue), those with aPL or antiphospholipid syndrome sometimes have an additional immune disorder. Although there are other disorders on the list, systemic lupus erythematosis is the most common autoimmune disorder linked to those with aPL.

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When to see a doctor

If you have an autoimmune condition like SLE, speak with your physician about whether or not you should be tested for antiphospholipid antibodies. If you are experiencing any of the following symptoms, please seek medical attention immediately:

  • Signs of a stroke: Numbness, weakness, or paralysis of your face, arm, or leg, impaired vision, or sudden and severe headache, or difficulty with speaking or understanding speech.
  • Signs of deep vein thrombosis: Pain, tenderness, redness, or swelling in your leg or arm
  • Signs of a pulmonary embolism (when one or more arteries in your lungs become blocked) : Pain or shortness of breath, chest pains that worsen with deep breathing, cough that may produce bloody or blood streaked sputum.
  • Unexplained bleeding: Any unexplained bleeding from the nose or gums, unusually heavy menstrual cycle, black or bright red stool, vomiting that looks like coffee grounds or is bright red.

*If you are pregnant and experience spotting or bleeding, this may be a sign of a miscarriage or other pregnancy complications. If you have suffered from several miscarriages or severe and unexplained complications during pregnancy, it could be related to antiphospholipid syndrome. Back to top  


Tests for antiphospholipid syndrome

Blood tests are used to make a diagnosis for APS looking for at least one of these following antibodies in your blood:Antiphospholipid Syndrome

  1. Lupus anticoagulant
  2. Anti-cardiolipin
  3. Prolonged PTT
  4. Beta-2 glycoprotien 1

A diagnosis will be confirmed after the antibodies appear in your blood at least twice in tests that are taken at least 12 weeks apart. Back to top  


Causes of APS

Like most autoimmune diseases, the definitive cause of antiphospholipid syndrome remains unknown. What is known is that the body produces antibodies that target the proteins that bind the phospholipids (a type of fat that is in your blood that plays a key role in clotting). The antibodies normally attack the invaders like viruses and bacteria, but when they behave incorrectly and begin to attack the phospholipid-binding proteins, your body may then begin to clot abnormally. Three factors that may be associated with developing APS are:

  1. Infections: Infections like HIV, syphilis, Hepatitis C, Lyme disease do have a higher incidence of having antiphospholipid antibodies.
  2. Medications:  The antibiotic amoxicillin, hydralazine taken for high blood pressure, quinidine which is taken for regulation of heart rhythm, and an anti-seizure medication called phenytoin may lead to a higher risk for the development of antiphospholipid antibodies.
  3. Genetics or Heredity: Research indicates that relatives of those with antiphospholipid syndrome have an increased likelihood of having the antibodies themselves, even though the disorder is not considered to be hereditary.

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Treatment for APS

The treatment plan will be specific to the individual and their current health status with regards to the APS symptoms that they are experiencing. Ideally, any treatment regimen will be directed towards thinning (anticoagulating) the blood to prevent clotting. Here are some medications (anticoagulants) used to treat APS and prevent blood clots:

  • Lupus MedicationsWarfarin (Coumadin)
  • Heparin
  • Aspirin
  • Prednisone (used to suppress the immune system activity and inflammation)
  • For those with SLE who have APS, hydroxychoroquine or Plaquenil can also add some protection against blood clots.
  • For those who have aPL antibodies but have not shown symptoms, low-dose aspirin is generally recommended by the treating physician.
  • For women who wish to get pregnant, but have had a history of miscarriage, the physician may prescribe heparin (prevents blood clots) and low-dose aspirin.

Things to note if you are taking anticoagulants (your blood may not clot as easily so it is best to avoid injuring yourself and avoid bleeding):

  • Shave with an electric razor rather than a blade
  • Use a softer toothbrush and waxed floss to protect the gums
  • Be extra cautious around sharp objects like scissors and knives
  • Try to avoid any activities or sports that may cause bruising or injury or may cause you to fall.

*It is very important to speak with your physician about any other medications or supplements that you are taking as they may cause the anticoagulant medications to be less effective or interact in a dangerous way with your anticoagulants. Also ask about any dietary restrictions that can either increase or reduce the medication’s blood-thinning effect. Back to top  


APS Prevention

Even if you have the antibodies associated with APS, there are things you can do to reduce the risk of developing blood clots or any other signs or symptoms.

Things you can do to reduce the chances of developing blood clots:

  • Don’t smoke or use tobacco products
  • Keep your cholesterol and triglyceride levels low
  • Get up and move around during long plane flights or other times when you have to sit or lie down for extended periods.

The risk of developing clots increases if you:

  • Become pregnant
  • Take oral contraceptives
  • Have surgery

New Research:

The National Institute of Neurological Disorders and Stroke (NINDS) and the National Institutes of Health (NIH) are funding research through medical grants to look for ways to reduce clotting and prevent stroke.  In this research, they are also examining the role of pregnancy loss associated with APS, along with possible inherited risks factors.  

Antiphospholipid Syndrome Clinical Trials:

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While there is no cure for antiphospholipid syndrome, there are very successful ways to manage and treat this condition. If you are diagnosed with APS, be mindful of any symptoms that are new to you, keeping good medical records with dates and descriptions of symptom activity. Clearly and regularly communicate with your medical provider about your responses to the medications as well as your general wellness. This will help you and your physician devise the optimum course of action and make necessary adjustments to reach the best possible outcome as well as to help prevent any further complications. Back to top  


Sources:,,>,,,>, medlineplus>,,,

Author: Karrie Sundbom

Updated by: Kelli Roseta 2016

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All resources provided by us are for informational purposes only and should be used as a guide or for supplemental information, not to replace the advice of a medical professional. The personal views expressed here do not necessarily encompass the views of the organization, but the information has been vetted as a relevant resource. We encourage you to be your strongest advocate and always contact your healthcare practitioner with any specific questions or concerns.