Antiphospholipid Syndrome: Causes, Symptoms, and Treatments

The presence of multiple thrombosis or repeated miscarriages should raise the suspicion of antiphospholipid syndrome. What should you know about this disease?

Reviewed and approved by the doctor Mariel Mendoza.

Written by Mariel Mendoza

Last update: 17 October, 2022

Antiphospholipid syndrome occurs when the immune system creates antibodies that attack the body’s own tissues (autoantibodies). As a result, blood clots form in the arteries and veins , preventing proper blood flow. This results in symptoms associated with decreased or obstructed flow.

In particular, it often manifests with episodes of thrombosis and repeated miscarriages. Unfortunately, there’s no specific cure for this syndrome. However, several medications are available that reduce clot formation and other associated complications. Want to know more about it? Read on!

The cause of antiphospholipid syndrome is not well defined

Antiphospholipid syndrome can occur due to an underlying disease, such as an autoimmune disorder. However, there are cases in which this cause doesn’t exist. It may have an associated genetic component, as is the case with most autoimmune diseases.

Systemic lupus erythematosus is the condition most associated with its occurrence. However, other conditions also increase the risk of blood clots produced by autoantibodies. These include the following:

• Pregnancy
• Prostration
• Surgeries
• Tobacco smoking
• Taking oral contraceptives or estrogen replacement therapy at menopause
• High triglyceride and cholesterol levels

How is the diagnosis made?

The diagnosis is made by serological measurement of autoantibodies. These must appear at least twice consecutively in the blood in tests performed 12 or more weeks apart. Nowadays, different types of autoantibodies are measured:

• Anti-cardiolipin
• Anti-β2-glucoprotein I
• Lupus anticoagulant
• Other antiphospholipid antibodies that aren’t usually measured routinely

However, it’s possible to have the presence of antiphospholipid autoantibodies and have no symptoms. The diagnosis is confirmed only in the presence of autoantibodies and clinical manifestations (thrombosis or pregnancy complications).

The symptoms of antiphospholipid syndrome

The clinical manifestations of this syndrome depend on where the blood clots are lodged. Complications include the following:

• Renal insufficiency
• Cerebrovascular disease
• Pulmonary or cardiovascular problems
• Pregnancy difficulties

How autoantibodies generate thromboembolism

The autoantibodies present in antiphospholipid syndrome act – as the name suggests – against one’s own tissues. Thus, they increase the risk of blood clot formation due to cell damage in the blood vessels.

However, thrombosis doesn’t usually occur in the absence of other conditions that promote clottings, such as prolonged inactivity, prostration, pregnancy, or recent surgery. Other risk factors include the following:

• Estrogen use
• Associated autoimmune diseases
• Obesity
• Alteration of lipid profiles
• Arterial hypertension
• Hardening of the arteries (atherosclerosis)

Antiphospholipid syndrome can affect any vascular bed

Thrombosis in antiphospholipid syndrome can occur anywhere in the cardiovascular system. Thus, it can affect any organ of the body. Symptoms will depend on where it occurs.

In addition, there are other associated conditions, such as a decrease in the number of platelets (thrombocytopenia). This is due to the number of blood cells that are used in the production of clots. This increases the likelihood of bleeding, especially in the nose and gums.

It’s also possible to experience marbled skin (“blotchy” skin or livedo reticularis ) and skin ulcers.

Clinical manifestations according to affected organs

• Kidney failure due to thrombosis of large vessels or glomerular capillaries (thromboembolic microangiopathy).
• Deep vein thrombosis. This manifests with pain, swelling, and redness in the lower limbs.
• Pulmonary embolism due to the migration of a clot into the respiratory circulation. When a clot lodges in the lung, it is manifested by a sudden shortness of breath, chest pain, and a cough with expectoration of blood.
• Cerebrovascular disease or transient ischemic attack, which depends on the extent of involvement of the central nervous system circulation. It may present as paralysis or weakness of the face, arm, or leg; visual disturbances or slurred speech; and a sudden, severe, generalized headache.
• Cardiovascular disease due to obstruction of the coronary circulation (may produce infarction). They can also lodge in the heart valves and travel through the bloodstream (arterial embolism) or damage and thicken them.
• Other neurological conditions due to decreased blood flow such as migraines, seizures, and chorea.
• In pregnancy , complications range from repeated miscarriages to intrauterine fetal death. In addition, it can lead to preeclampsia (increased blood pressure with loss of protein in the urine), intrauterine growth restriction, and preterm delivery.

Treatment of antiphospholipid syndrome

Treatment of antiphospholipid syndrome is based on preventing clot formation through the use of oral anticoagulant (blood thinning) or antiplatelet drugs. In addition, risk factors associated with thrombosis should be addressed.

Cases of acute thrombotic episodes are initially managed with intravenous heparin, followed by oral anticoagulants (warfarin). The use of anticoagulants should be monitored with a blood test to decrease the risk of bleeding, either through a wound or under the skin.

After treating the acute event, people with this syndrome should take oral anticoagulants to prevent the reoccurrence of blood clots in the veins. To avoid arterial periods, antiplatelet drugs such as aspirin and clopidogrel are usually used.

In the case of pregnant women, it’s possible to carry the pregnancy to term with proper monitoring and the use of medications. Treatment includes heparin or heparin with low-dose aspirin because warfarin cannot be administered in these cases because it can affect the fetus.

What to remember?

The presence of one or more episodes associated with the formation of blood clots or repeated pregnancy loss (or other pregnancy complication) that can’t be explained by another cause should raise a suspicion of antiphospholipid syndrome. Although it has no specific cure, the symptoms of this condition can be controlled. It’s even possible to carry a pregnancy to term. Therefore, in case of suspicion, it’s best to consult a rheumatologist as soon as possible.