Antiphospholipid Syndrome

What is Antiphospholipid Syndrome?

Antiphospholipid Syndrome (APS) is an autoimmune disorder characterized by the production of antibodies that mistakenly attack some normal proteins in the blood. The functioning of these antibodies can lead to blood clotting within the veins and arteries as well as serious pregnancy complications like miscarriages and stillbirths. Blood clotting in the legs due to the disorder can cause a condition named deep vein thrombosis. APS can also cause blood clotting within various organs such as the kidney and lungs.

Image Source via Wikimedia Commons

The condition is also known as Antiphospholipid Antibody Syndrome and Hughes Syndrome.

Antiphospholipid Syndrome Incidence

There is a lack of information regarding the incidence statistics of the disorder. Various researches suggest that approximately 1 to 5% of the general healthy population have antiphospholipid antibodies. Over 50% of such individuals suffer from Primary APS. According to some additional studies, these antibodies may be responsible for one-third of the total cases stroke in people aged below 50 years.

The prevalence statistics show the disorder to have a higher frequency among women compared to men. It does not generally occur in children.

Antiphospholipid Syndrome Classification

The disorder has been classified into the two following categories:

Picture 1 – Antiphospholipid Syndrome

Primary APS

If the condition is not accompanied by any other autoimmune disorder like Systemic Lupus Erythematosus, it is referred to as primary APS.

Secondary APS

The disorder is classified as secondary APS if a patient has Lupus Erythematosus or any similar autoimmune disorder.

Antiphospholipid Syndrome Causes

The main cause for this disease is the production of the autoantibodies (antibodies that attack healthy cells) that destroy the proteins responsible for binding the phospholipids, the type of fat that plays the most important role in coagulation (blood clotting). Under normal circumstances, antibodies attack harmful body invaders like bacteria and viruses. Hughes Syndrome occurs when the antibodies begin to attack the phospholipid-binding proteins, causing abnormal blood clotting.

The exact reasons behind the production of the destructive antibodies in primary APS are still not known. The following factors are associated with the development of antiphospholipid antibodies, but they are not always the principal cause of the condition.


Individuals having hepatitis C, HIV infection, syphilis, malaria etc are more likely to have these antibodies.


Using certain drugs like the heart rhythm-regulating medicine quinidine, high blood pressure drug Hydralazine, the antibiotic amoxicillin and the anti-seizure medicine phenytoin are possible risk factors.

Oral Contraceptives

Clotting of blood may occur in a woman following the use of oral birth control pills that contains estrogen.

Genetic Factors

APS is not considered to be a hereditary disorder. However, research suggests that individuals with a family history of Antiphospholipid Antibody Syndrome are more at risk of developing the antibodies.

Antiphospholipid Syndrome Symptoms

The principal symptoms of APS are the various disorders caused by blood coagulation in different parts of the body. The common symptoms include:

  • Deep vein thrombosis (DVT) caused by the presence of blood clots in the legs is a main characteristic of APS. This condition can manifest in pain, especially in the knee joint and swollen legs.
  • The blood clots can travel to important organs like lungs and kidney to cause serious conditions like pulmonary embolism and renal vein thrombosis.
  • Blood clot formation in the brain, which can even result in a stroke.
  • Various eye problems, such as blurred vision.
  • Fatigue and tiredness, which are some common signs of the disease.
  • Symptoms of Hughes Syndrome during pregnancy, which include preeclampsia and high blood pressure.

Following are some other possible symptoms:

Neurological problems

Sometimes, blood flow to some parts of the brain gets disrupted due to blood clot formation. This can lead to a number of neurological symptoms like migraines, chronic headache, seizures and dementia.


Some individuals can have a red rash along with livedo reticularis (a net-like pattern) on the skin around knees and wrists.

Cardiovascular disease

Various heart valve problems can occur in people suffering from this autoimmune condition. The four valves in the human body control the blood flow through the four chambers of the heart and keep it flowing in a single direction by opening and closing properly. In APS, however, the mitral valve generally gets affected and starts developing masses that can lead to blood leakage (regurgitation). In some cases, the disorder may also affect the aortic valve.


In some people, it can cause lowering of the platelet levels (thrombocytopenia). Platelets play a central role in normal clotting. The low platelet count often does not cause any visible symptoms. However, some individuals may experience unexplained episodes of bleeding from the nose and gums. Sometimes, there might be bleeding into the skin which results in small red patches on the skin (petechiae).

Rare symptoms of APS can include:

  • Movement disorders causing uncontrollable jerking of the body and limbs (chorea)
  • Sudden hearing loss
  • Cognitive problems like poor memory
  • Mental health problems including psychosis and depression

Antiphospholipid Syndrome Prevention

It is not possible to prevent the disease. However, one can make certain lifestyle changes to reduce the risk of development of abnormal blood coagulation. These include:

  • Increasing the level of physical activity
  • Giving up smoking
  • Avoiding taking medications that are likely to increase the risk of producing the antibody responsible for causing this blood clotting disorder

Antiphospholipid Syndrome Diagnostic Criteria

The clinical diagnostic criteria for APS include the following:

Vascular thrombosis

One or more episodes of small-vessel, venous or arterial thrombosis in any organ or tissue is the most common criteria of APS. Objective validated criteria must be used for confirming the thrombosis. For histopathological confirmation, a sufferer should not experience significant inflammation in vessel wall due to the thrombosis.

Pregnancy-related issues

Repeated fetal death beyond the tenth week of pregnancy without any evident reason is the second criterion for the condition. The fetal morphology is usually normal when examined directly or by ultrasound. Premature births before the thirty-fourth week of pregnancy due to severe pre-eclampsia or eclampsia is considered to be a clinical criterion as well. Another pregnancy related criterion is at least 3 successive spontaneous abortions before tenth week of gestation without any hereditary chromosomal factor or maternal hormonal and anatomical abnormalities.

Antiphospholipid Syndrome Diagnosis

Doctors study the symptoms present in the patient and order various diagnostic tests to confirm the presence of APS. Sometimes, a patient may develop certain symptoms that resemble those caused by the condition without having the condition. Naturally, performing proper diagnostic exams is important to avoid any misdiagnosis.

Individuals with one or more diagnostic criteria undergo detailed physical therapy. Doctors also study their medical history. Various blood tests are used for detecting the antibodies that generally cause Hughes Syndrome. The blood tests are performed for detecting at least 1 of the following 3 antibodies in the blood of patients:

  • Lupus anticoagulant
  • Beta-2 glycoprotein I (B2GPI)
  • Anti-cardiolipin

The antibodies must be detected in the blood sample at least twice, when the tests are conducted 12 weeks apart, for confirming the diagnosis.

Screening tests may produce positive results for syphilis in people having antiphospholipid antibodies even when they do not really have the disease. In these cases, various confirmatory tests are used for ruling out syphilis infection in the individuals.

Imaging tests like MRI and CT are not useful in most cases. However, a brain MRI can be used for detecting any blood clots in the brain.

Antiphospholipid Syndrome Differential Diagnosis

It is important to eliminate the possibility of the following disease while diagnosing APS:

  • Disseminated Intravascular Coagulation
  • Infective Endocarditis
  • Thrombotic Thrombocytopenic Purpura
  • Sneddon’s syndrome
  • Inherited thrombophilia

Antiphospholipid Syndrome Treatment

The treatment of APS begins with administration of certain medications that reduce the tendency of blood coagulation in patients.

Standard Initial Treatment

The standard treatment includes a combination of blood-thinning (anticoagulant) medications to reduce the thrombosis. The following medications are generally used for this purpose:


Typically, patients are first given an infusion of heparin, a blood thinner medicine, combined with another anticoagulant (likely warfarin) in the pill form.


The heparin is discontinued by doctors after a certain amount of time. But, the warfarin (Coumadin) is continued for a long time. Sometimes, patients need to continue the warfarin infusion all lifelong.


A doctor may prescribe a low-dose aspirin to the patient for treating the disorder.

Treatment during pregnancy

It is very difficult to carry out the anticoagulation therapy in pregnant women. Treating APS during pregnancy is very expensive, requiring regular injections. It also carries considerable risks of serious side effects.


Certain forms of heparin, such as dalteparin (Fragmin) and enoxaparin (Lovenox), are considered as low molecular weight heparin. Patients can inject themselves subcutaneously (under the skin) with these types of heparin. This medication is considered to be safe to treat Antiphospholipid Antibody Syndrome during pregnancy.


Doctors often recommend patients to take one pill of aspirin everyday along with the heparin injection. The aspirin dosage increases the chances of having a successful pregnancy.


This medication is generally not recommended to pregnant patients as it may cause various birth defects. In some rare cases, a doctor may prescribe warfarin during pregnancy if its benefits outweigh the potential risks.

The dosage of the anticoagulant medication is monitored carefully by the doctor to make sure the blood is capable of coagulating to stop the bleeding if the patient suffers from a cut or bruise.

Other Medications

Doctors may prescribe the following medications for treating advanced cases of this condition:

  • Steroids
  • Antiglobulin medications
  • Immune-suppressing drugs

The benefits and usefulness of these medications are still under examination and they are also associated with a number of side effects. The additional drugs mentioned above are used only in cases where blood-thinners fail to manage the condition.

Antiphospholipid Syndrome Diet and Dietary Supplements

Certain foods and diet supplements can affect the functioning of the anticoagulants by interacting with them. People undergoing APS treatment should remember the following guidelines:

Dietary considerations

Vitamin K is known to reduce the effects of warfarin, so it is important to monitor one’s daily vitamin K intake when taking warfarin. Alcohol and cranberry juice may increase the blood-thinning effects of warfarin dangerously. Due to this reason, the patient should consult his or her physician regarding the consumption of these drinks.

Dietary supplements

Certain herbal and vitamin supplements are known to cause serious drug interactions with warfarin. Herbal products and supplements including stomach remedies, multivitamins, green tea products and garlic are most likely to result in dangerous drug interactions.

Antiphospholipid Syndrome Complications

The complications of APS depend on the organs affected by blood clotting and the degree of the blood flow obstruction to a certain organ. The possible problems include:

  • ·         Kidney failure
  • ·         Stroke
  • Gangrene
  • Heart attack
  • Blockage of blood flow to certain limbs
  • Pulmonary hypertension
  • Pulmonary embolism
  • Pregnancy complications (preeclampsia, miscarriage, stillbirth)

Catastrophic Antiphospholipid Antibody Syndrome

Catastrophic APS is a condition in which the blood coagulation continues in a patient in spite of the best treatment. It occurs in around 1% of the total cases of Antiphospholipid Antibody Syndrome. Development of blood clots in different regions of the body may lead to multiple organ failure.  Catastrophic APS often occur after surgery, trauma or infection. The symptoms of this condition may vary according to the organs affected and can include:

  • Abdominal pain
  • Confusion
  • Edema (swelling) in different extremities
  • Progressive breathlessness
  • Seizures
  • Coma

Antiphospholipid Syndrome Prognosis

It is possible to cure the condition with proper medication and follow-up. However, APS patients often need to remain on medication for the rest of their lives. Individuals suffering from primary APS usually live a long and healthy life with medication and certain lifestyle changes. Secondary APS patients also have positive prognosis, but their life expectancy may be affected by the associated conditions and complications. Leaving APS untreated can cause permanent organ damage and death.


Picture 2 – Antiphospholipid Syndrome Image

APS caused by medication or infection are often temporary and may resolve automatically once the medication is discontinued or the infection is cured.

In some severe cases, APS patients develop Catastrophic Antiphospholipid Antibody Syndrome where the blood clot formation continues in spite of the best treatments. This condition can even turn fatal.

Antiphospholipid Syndrome Support Groups

There are numerous forums and foundations that provide useful information about Antiphospholipid Antibody Syndrome to help the patients manage the disease. These include:

American Autoimmune Related Diseases Association, Inc.

22100 Gratiot Ave.

East Detroit, Michigan 48021

Tel: (586)776-3900

Fax: (586)776-3903



Lupus Foundation of America, Inc.

2000 L Street NW

Suite 710

Washington, DC 20036

United States

Tel: (202)349-1155

Fax: (202)349-1156



Antiphospholipid Antibody Support Group

Marvin Nelson

4228 Deer Path Road

Apex, North Carolina 27539-7282

Tel: (919)362-8977



Antiphospholipid Syndrome is a serious and potentially life threatening disorder requiring early diagnosis and prompt treatment. Proper and timely cure allows sufferers to live a long, healthy life and even participate in normal social activities.

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