10 Warning Signs and Symptoms of Antiphospholipid Syndrome You Should Know

Antiphospholipid syndrome (APS), also known as antiphospholipid antibody syndrome, is an autoimmune disorder that causes blood to clot more easily than normal. This condition occurs when the immune system mistakenly produces antibodies that attack phospholipids, which are fat molecules found in cell membranes and blood. These abnormal antibodies can lead to blood clots in arteries and veins, pregnancy complications, and various other health problems throughout the body.

Understanding the symptoms of antiphospholipid syndrome is crucial for early detection and management. While some people with APS may not experience any symptoms, others may face serious complications. The condition can affect anyone, but it is more common in women, particularly during childbearing years. Recognition of these warning signs can help you seek timely medical attention and prevent potentially life-threatening complications.

Here are the 10 most important symptoms and warning signs of antiphospholipid syndrome that you should be aware of:

1. Blood Clots in the Legs (Deep Vein Thrombosis)

One of the most common symptoms of antiphospholipid syndrome is the formation of blood clots in the deep veins of the legs, a condition known as deep vein thrombosis (DVT). This occurs when the abnormal antibodies cause blood to clot inappropriately within the veins.

Signs of DVT include:

• Swelling in one or both legs, typically starting in the calf
• Pain or tenderness in the leg, which may feel like cramping or soreness
• Warmth in the affected area
• Red or discolored skin on the leg
• Visible surface veins

DVT is particularly concerning because the clot can break loose and travel through the bloodstream to the lungs, causing a pulmonary embolism, which is a life-threatening emergency. If you experience sudden leg swelling accompanied by pain, it’s essential to seek immediate medical attention.

2. Pulmonary Embolism

A pulmonary embolism occurs when a blood clot travels to the lungs and blocks one or more pulmonary arteries. This is one of the most dangerous complications of antiphospholipid syndrome and requires emergency medical treatment.

Symptoms of pulmonary embolism include:

• Sudden shortness of breath that appears without obvious cause
• Sharp chest pain that worsens with deep breathing or coughing
• Rapid or irregular heartbeat
• Coughing up blood or blood-tinged mucus
• Lightheadedness or dizziness
• Excessive sweating
• Anxiety or feeling of impending doom

People with APS have a higher risk of developing pulmonary embolism, especially if they’ve already had deep vein thrombosis. This condition can be fatal if not treated promptly, so recognizing these symptoms and seeking immediate emergency care is critical.

3. Recurrent Miscarriages and Pregnancy Complications

Antiphospholipid syndrome is a leading cause of recurrent pregnancy loss. The antibodies can affect the placenta by causing blood clots in the placental blood vessels, which reduces blood flow and nutrients to the developing fetus.

Pregnancy-related symptoms and complications include:

• Multiple miscarriages, particularly after the 10th week of pregnancy
• One or more unexplained deaths of a normal fetus after 34 weeks of gestation
• Premature birth before 34 weeks due to severe preeclampsia or placental insufficiency
• Preeclampsia (high blood pressure and protein in urine during pregnancy)
• Intrauterine growth restriction (baby is smaller than expected)
• Stillbirth

Women with APS who become pregnant require close monitoring and specialized care throughout their pregnancy. If you have experienced multiple unexplained miscarriages, it’s important to discuss testing for antiphospholipid syndrome with your healthcare provider.

4. Stroke and Transient Ischemic Attack (TIA)

Blood clots formed due to antiphospholipid syndrome can travel to the brain and cause a stroke or transient ischemic attack (TIA), also known as a “mini-stroke.” These neurological events occur when blood flow to part of the brain is blocked.

Warning signs include:

• Sudden numbness or weakness of the face, arm, or leg, especially on one side of the body
• Confusion or difficulty speaking or understanding speech
• Trouble seeing in one or both eyes
• Difficulty walking, dizziness, or loss of balance and coordination
• Severe headache with no known cause
• Temporary loss of vision in one eye

Young people with APS are at increased risk of stroke compared to the general population. A TIA has similar symptoms to a stroke but typically resolves within minutes to hours. However, a TIA should be treated as a medical emergency because it’s often a warning sign that a full stroke may occur in the near future.

5. Skin Changes and Rashes

Antiphospholipid syndrome can affect the small blood vessels in the skin, leading to various visible changes. These skin manifestations are often one of the more recognizable signs of the condition.

Common skin symptoms include:

• Livedo reticularis: A lacy, purplish, mottled pattern on the skin, particularly on the legs and arms, that becomes more visible in cold temperatures
• Skin ulcers, especially around the ankles
• Small red spots or petechiae caused by bleeding under the skin
• Areas of skin necrosis (tissue death) in severe cases
• Painful nodules under the skin
• Splinter hemorrhages under the fingernails

Livedo reticularis is particularly associated with APS and appears as a net-like pattern of reddish-purple or blue discoloration. While it can occur in healthy individuals, especially in cold weather, persistent livedo reticularis should prompt evaluation for antiphospholipid syndrome, particularly if accompanied by other symptoms.

6. Thrombocytopenia (Low Platelet Count)

Many people with antiphospholipid syndrome develop thrombocytopenia, which is a lower-than-normal number of platelets in the blood. Paradoxically, despite having fewer platelets, which normally help blood clot, people with APS still have an increased risk of clotting due to the abnormal antibodies.

Signs and symptoms of thrombocytopenia include:

• Easy or excessive bruising
• Superficial bleeding into the skin appearing as pinpoint-sized reddish-purple spots (petechiae)
• Prolonged bleeding from cuts or wounds
• Bleeding gums or nosebleeds
• Blood in urine or stools
• Unusually heavy menstrual periods
• Fatigue

The thrombocytopenia in APS is usually mild to moderate and may not cause symptoms. However, it’s often discovered during routine blood work, which is why laboratory testing is important when APS is suspected.

7. Heart Problems

Antiphospholipid syndrome can affect the heart in several ways, from valve abnormalities to heart attacks. The antibodies can damage heart valves and cause blood clots to form in the coronary arteries.

Cardiac symptoms and complications include:

• Heart valve disease: Thickening or dysfunction of heart valves, particularly the mitral valve
• Heart attack: Chest pain or pressure, shortness of breath, nausea, and pain radiating to the arm, jaw, or back
• Heart murmurs detected during physical examination
• Irregular heartbeat or palpitations
• Chest discomfort or tightness
• Fatigue and weakness

People with APS, particularly young adults, have an increased risk of heart attack compared to those without the condition. Heart valve abnormalities are relatively common in APS, though they may not always cause symptoms and are often detected during echocardiography.

8. Neurological Symptoms Beyond Stroke

In addition to stroke and TIA, antiphospholipid syndrome can cause a range of other neurological symptoms due to impaired blood flow to various parts of the brain and nervous system.

These symptoms include:

• Chronic headaches or migraines, which may be severe and recurring
• Cognitive dysfunction, including memory problems, difficulty concentrating, and confusion
• Seizures without another identifiable cause
• Chorea (involuntary, rapid, jerky movements)
• Dementia or progressive cognitive decline
• Numbness or tingling in extremities
• Vision disturbances, including double vision or temporary vision loss
• Dizziness or vertigo
• Balance problems

Some people with APS experience subtle cognitive symptoms that may be mistaken for stress, depression, or normal aging. These can include difficulty finding words, problems with short-term memory, and decreased ability to multitask or process information quickly.

9. Kidney Problems

The kidneys can be significantly affected by antiphospholipid syndrome when blood clots form in the renal vessels. This can lead to kidney damage and reduced kidney function over time.

Symptoms of kidney involvement include:

• High blood pressure that’s difficult to control
• Protein in the urine (detected through laboratory testing)
• Blood in the urine (hematuria)
• Reduced urine output
• Swelling in the legs, ankles, feet, or around the eyes
• Fatigue and weakness
• Nausea and loss of appetite

Kidney disease associated with APS may develop gradually and without obvious symptoms in the early stages. Regular monitoring of kidney function through blood and urine tests is important for people diagnosed with antiphospholipid syndrome to detect any problems early.

10. Eye Problems and Vision Changes

Blood clots affecting the blood vessels in or leading to the eyes can cause various vision problems in people with antiphospholipid syndrome. These ocular manifestations can range from temporary to permanent.

Eye-related symptoms include:

• Sudden loss of vision in one or both eyes
• Temporary vision loss (amaurosis fugax) that typically resolves within minutes
• Blurred or double vision
• Visual field defects (blind spots)
• Eye pain or discomfort
• Seeing flashing lights or floaters
• Retinal vein or artery occlusion

Vision problems in APS occur when blood clots block the blood vessels that supply the retina or optic nerve. Sudden vision loss, even if temporary, should be treated as a medical emergency because it may indicate an impending stroke or permanent vision damage.

Main Causes of Antiphospholipid Syndrome

The exact cause of antiphospholipid syndrome is not fully understood, but it involves the immune system producing abnormal antibodies that attack phospholipids. Several factors contribute to the development of this condition:

Autoimmune Disorders: APS commonly occurs alongside other autoimmune conditions, particularly systemic lupus erythematosus (SLE). About 30-40% of people with lupus also have antiphospholipid antibodies, though not all develop the syndrome. The condition can also be associated with other autoimmune diseases such as rheumatoid arthritis, Sjögren’s syndrome, and autoimmune thyroid disease.

Genetic Factors: While APS is not directly inherited, there appears to be a genetic predisposition. Having a family member with APS or other autoimmune conditions may increase your risk. Certain genetic markers have been identified that may make individuals more susceptible to developing the antibodies.

Infections: Some viral and bacterial infections may trigger the production of antiphospholipid antibodies. These include hepatitis C, HIV, syphilis, Lyme disease, and certain other infections. In most cases, the antibodies disappear after the infection clears, but in some individuals, they persist and lead to APS.

Medications: Certain medications have been associated with the development of antiphospholipid antibodies, including some blood pressure medications, anti-seizure drugs, and antibiotics. However, medication-induced antibodies usually disappear once the drug is discontinued and rarely cause symptoms.

Primary vs. Secondary APS: When antiphospholipid syndrome occurs on its own without another autoimmune disease, it’s called primary APS. When it occurs alongside another condition like lupus, it’s called secondary APS. The cause may differ slightly between these two forms.

Hormonal Factors: The condition is more common in women of childbearing age, suggesting that hormones may play a role in its development. However, the exact mechanism is not fully understood.

Frequently Asked Questions

What is the difference between antiphospholipid syndrome and lupus?

Antiphospholipid syndrome and lupus are both autoimmune conditions, but they are distinct diseases. APS specifically involves antibodies that attack phospholipids and cause blood clotting problems. Lupus is a broader autoimmune disease that can affect multiple organs and systems. However, many people with lupus also have APS, which is then called secondary antiphospholipid syndrome. APS can also occur independently, known as primary APS.

Can you have antiphospholipid antibodies without having the syndrome?

Yes, it’s possible to have antiphospholipid antibodies in your blood without developing antiphospholipid syndrome. In fact, about 1-5% of healthy individuals test positive for these antibodies. To be diagnosed with APS, you must have both the presence of antiphospholipid antibodies (confirmed on at least two occasions at least 12 weeks apart) and clinical evidence of the syndrome, such as blood clots or pregnancy complications.

Is antiphospholipid syndrome life-threatening?

Antiphospholipid syndrome can be life-threatening due to the serious complications it can cause, such as stroke, pulmonary embolism, heart attack, and pregnancy complications. However, with proper diagnosis and management, most people with APS can lead normal, active lives. The key is early detection, appropriate medical care, and following your healthcare provider’s recommendations for managing the condition.

Can antiphospholipid syndrome be cured?

Currently, there is no cure for antiphospholipid syndrome. It is a chronic condition that requires ongoing management. However, the symptoms and complications can be effectively controlled with appropriate medical care. Many people with APS live full, active lives with proper treatment and monitoring. Research continues into better understanding the condition and developing new approaches to management.

How is antiphospholipid syndrome diagnosed?

Diagnosis of APS requires both clinical criteria (such as blood clots or pregnancy complications) and laboratory criteria (presence of specific antiphospholipid antibodies). Blood tests check for three types of antibodies: lupus anticoagulant, anticardiolipin antibodies, and anti-beta-2 glycoprotein I antibodies. These antibodies must be present on two or more occasions at least 12 weeks apart to confirm the diagnosis. Your doctor will also evaluate your medical history and any symptoms you’ve experienced.

Can men get antiphospholipid syndrome?

Yes, men can develop antiphospholipid syndrome, although it is more common in women. In men, APS typically presents with blood clots in the legs or lungs, stroke, or heart attack rather than pregnancy-related complications. Men with APS face similar risks for blood clotting complications and require the same careful monitoring and management as women with the condition.

What should I do if I suspect I have antiphospholipid syndrome?

If you experience symptoms such as unexplained blood clots, recurrent miscarriages, stroke at a young age, or the characteristic skin rash (livedo reticularis), you should consult your healthcare provider promptly. Be prepared to discuss your complete medical history, including any autoimmune conditions in your family. Your doctor may order blood tests to check for antiphospholipid antibodies and may refer you to a rheumatologist or hematologist for specialized evaluation and care.

Can pregnancy be successful with antiphospholipid syndrome?

Yes, many women with antiphospholipid syndrome can have successful pregnancies with proper medical care and close monitoring. However, APS pregnancies are considered high-risk and require specialized care from healthcare providers experienced in managing this condition. With appropriate treatment and surveillance throughout pregnancy, the majority of women with APS can carry a pregnancy to term and deliver a healthy baby. If you have APS and are planning to become pregnant, it’s important to discuss this with your healthcare team before conception.

References:

• Mayo Clinic – Antiphospholipid Syndrome
• Johns Hopkins Medicine – Antiphospholipid Syndrome
• NHS – Antiphospholipid Syndrome
• American College of Rheumatology – Antiphospholipid Syndrome
• National Center for Biotechnology Information – Antiphospholipid Syndrome