Antiphospholipid syndrome (also known as antiphospholipid antibody syndrome, APS, APLS or Hughes syndrome) is an autoimmune condition caused by antiphospholipid antibodies that results in excessive blood clotting.
Antibodies are specific proteins that your body produces in order to fight off foreign substances. Phospholipids are a type of fats (lipids) containing phosphate. Antiphospholipid syndrome (APS) is a disease in which increased levels of various antibodies is responsible for thrombus (clot) formation in blood vessels. It is also known as Hughes syndrome or antiphospholipid antibody syndrome.1
How common is Antiphospholipid Syndrome?
One to five percent of the healthy general population is known to have Antiphospholipid antibodies. It is more common in females.1
Causes of Antiphospholipid Syndrome
Phospholipids are a type of fat that play an important role in blood clotting. In case you are diagnosed with APS, your body is mistakenly producing the antibodies against its own proteins that are responsible for binding these phospholipids. Thus, your blood would now have an abnormal clotting mechanism.
Types of APS
Two main types of antiphospholipid syndrome have been reported:
- Primary: In case there is no known underlying cause and you developed APS, you are said to have primary antiphospholipid syndrome.
- Secondary: In case you are suffering from another auto-immune disorder like systemic lupus erythematosus (SLE), or infections, or you have been taking certain medications, and you developed APS, it is secondary antiphospholipid syndrome.
Factors associated with developing APS
- The infections like HIV, syphilis, Lyme disease, hepatitis C.
- The medications like the heart rhythm normalizing medication – quinidine, the blood pressure lowering medication – hydralazine, the antibiotic – amoxicillin, the anti-epileptic medication – phenytoin.
- Genetic predispositions – Research has shown that the relatives of patients diagnosed with antiphospholipid syndrome are to some extent likely to have these antiphospholipid antibodies3.
Symptoms of Antiphospholipid Syndrome
Signs and symptoms of antiphospholipid syndrome may include:
- Blood clots in your lower limbs producing pain and swelling in legs– also known as deep vein thrombosis.
- These blood clots may that may travel through the blood vessels to your lungs – called pulmonary embolism, producing shortness of breath, palpitations, chest pain and you may cough up blood.
- Repeated miscarriages (stillbirths).
- Other complications of pregnancy with APS include high blood pressure and premature delivery.
- Peripheral arterial thrombosis – the blood clots may develop in the arteries of your legs or arms.
Other less common findings include:
- Neurological symptoms like headaches
- Cardiovascular disease
Diagnosing Antiphospholipid Syndrome
Both clinical and lab findings are used for the diagnosis of APS.
APS is diagnosed
- If you experience one or more episodes of abnormal blood clotting or miscarriage.
- If the antiphospholipid antibodies are found after lab testing of your blood.
The two kinds of antiphospholipid antibody tests are -
- Immunological tests - the anticardiolipin enzyme-linked immunoassay (ELISA)
- Coagulation-based tests done for lupus anticoagulant.
- A large number of individuals are positive in one of the two tests but negative in the other. So, in order to make a correct diagnosis of APS, both of the above tests are mandatory. Your doctor may ask you to repeat these tests after about 6 - 8 weeks for confirming the presence of anti phospholipid antibodies1.
Treatment for Antiphospholipid Syndrome
For a person who is having aPL antibodies in bloodstream and an episode of abnormal blood clotting, a temporary course of an anticoagulant (heparin) is given. Then, the patient is put on long-term or may be a life-long - treatment with another kind of anticoagulant medication (Warfarin).
The women who wish to get pregnant again after a series of miscarriages need special treatment. More so when these women are having moderate to high levels of aPL antibodies in their blood. They are treated with a low-dose aspirin and heparin.
Low-dose aspirin is also recommended for individuals having aPL antibodies but no signs and symptoms of APS1.
Pregnancy and the Antiphospholipid Antibody Syndrome
APS in pregnancy can lead to the complications. These include low-birth weight of the baby, miscarriages, a high blood pressure (preeclampsia), low birth-weight and preterm labour. A pre-pregnancy counselling is therefore recommended in these cases. This allows the doctor to closely monitor the new pregnancy from the beginning.
Heparin, low-dose aspirin, prednisone (a steroid) and Intravenous immunoglobulin (IVIG) are being used for the management of pregnancy in women with APS2.
If Antiphospholipid Syndrome is left untreated
The untreated APS can cause a permanent damage to the health of the patient or even prove fatal. The possible complications include:
- Failure of the kidneys: This results due to a decrease in the blood flow to kidneys from APS.
- Stroke: When the blood flow to any portion of your brain decreases, it can result in stroke. There is a chance of permanent neurological damage after a stroke.
- Lung problems: A high blood pressure in your lungs known as pulmonary hypertension can take place. Also, clots can reach your lungs leading to a condition called pulmonary embolism.
- Cardiovascular problems: When a clot gets formed in your lower limbs, it can cause damage to the valves located in the veins of your affected leg. This leads to chronic venous insufficiency as valves are not competent enough to get blood up to the heart. This further leads to discoloration and chronic swelling of legs as a result of impaired blood flow upwards to the heart. Damage to your heart can be another possible complication of this syndrome.
- Cardiovascular problems: When a clot gets formed in your lower limbs, it can cause damage to the valves located in the veins of your affected leg. This leads to chronic venous insufficiency as valves are not competent enough to get blood up to heart. This further leads to discoloration and chronic swelling of legs as a result of impaired blood flow upwards to the heart. Damage to your heart can be another possible complication of this syndrome.
- Pregnancy complications: As discussed, these include high blood pressure during pregnancy, repeated miscarriages and stillbirths, premature delivery of the newborn and low birth weight.
Prognosis for people with Antiphospholipid Syndrome
The outcome of antiphospholipid syndrome is dependant upon the intensity and the character of its manifestations. The earlier the treatment is started; the better would be the prognosis.
Citations (view all)
- 1. "Learning About Antiphospholipid Syndrome (APS)" NIH. Accessed on June 28, 2015. https://www.genome.gov/17516396
- 2. "Antiphospholipid Antibody Syndrome" University of Illinois - Urbana/Champaign Carle Cancer Center - Hematology Resource Page. Accessed June 29, 2015. http://www.med.illinois.edu/hematology/ptaps.htm
- 3. "Antiphospholipid Syndrome" MayoClinic – Diseases and Conditions. Accessed June 29, 2015. http://www.mayoclinic.org/diseases-conditions/antiphospholipid-syndrome/basics/definition/con-20028805
- 4. "Antiphospholipid Syndrome" University of IOWA healthcare. Accessed June 29, 2015. http://www.healthcare.uiowa.edu/labs/lentz/Information_For_Patients/PDF/Antiphospholipid%20Syndrome%20Brochure.pdf