Antiphospholipid syndrome: what is it, causes, treatment

Fast facts

• Antiphospholipid antibodies are present in 15–20% all cases deep vein thrombosis (blood clots) and in one third of new strokes occurring in people under the age of 50.
• Antiphospholipid antibodies are the leading cause of recurrent miscarriages and pregnancy complications when no other cause is found.
• Diagnosis and treatment are very important. Once the disease is diagnosed, adequate therapy can prevent recurrence of symptoms in most cases.
• The mainstay of treatment is to prevent blood clots with oral anticoagulants (blood thinners) or anti-platelet drugs.

• Thrombosis risk factors must be addressed. They include diabetes, arterial hypertension or high blood pressure, hypercholesterolemia or high cholesterol, obesity, smoking, menopausal estrogen therapy or contraception, and any major systemic autoimmune disease.

Antiphospholipid antibody syndrome (commonly called antiphospholipid syndrome or APS and SAFA) is an autoimmune disease that is present mainly in young women. Those with APS produce abnormal proteins called antiphospholipid autoantibodies in their blood.

This leads to abnormal blood flow and can lead to dangerous blood clots in the arteries and veins, problems with the developing fetus and pregnancy. People with this disorder may be healthy or have an underlying medical condition, most often systemic lupus erythematosus (usually called lupus or SLE).

APS affects women five times more often than men. Typically, the diagnosis is made between the ages of 30 and 40. Although up to 40% of SLE patients test positive for antiphospholipid autoantibodies, only half of them develop thrombosis and / or miscarriages. Like most autoimmune diseases, SAFA has a genetic component, although there is no direct parent-to-child transmission.

What is antiphospholipid syndrome (APS)?

Antiphospholipid antibody syndrome - an autoimmune disease that can cause frequent blockages in the arteries and veins and / or miscarriage.

The blockage occurs as a result of the presence of proteins in the blood called antiphospholipid autoantibodies (commonly called aPL), which are formed against a person's own tissues. These autoantibodies interfere with normal blood clotting, resulting in increased clot formation or thrombosis (in which blood flow stops due to a blockage in a vessel).

The damage caused by thrombosis can vary depending on where the thrombus is formed. For example, repeating small blood clots in the heart can cause thickening or damage heart valve with the risk of sudden cessation of blood flow due to a blood clot (the so-called arterial embolism).

Autoantibodies (aPL) can also be related to heart attacks in young adults with no known risk factors for heart disease. Blood clots in the arteries of the heart can lead to heart attacks, while blood clots in the arteries of the brain can lead to strokes. Blood clots from aPL can occur anywhere in the bloodstream and affect any organ in the body.

Blood clots (clots) that form in the veins are most common in the lower legs. Blood clots in the veins of the legs can rupture and spread to the lungs, causing a very serious condition called pulmonary embolism. Pulmonary embolism blocks blood flow to the lungs and decreases the amount of oxygen in the blood.

In some cases, recurrent thrombotic events can occur for a short time, resulting in progressive damage to several organs. This acute and life-threatening condition is called catastrophic antiphospholipid syndrome (CAFS). Patients with APS can suffer from other problems, including low platelet counts that cause skin discoloration (thrombocytopenic purpura).

In pregnant women, aPL in the blood can lead to early and late miscarriages and preeclampsia (high blood pressure and protein in the urine during pregnancy). The aPL was originally thought to be responsible for the formation of blood clots in the blood vessels of the placenta, causing fetal growth retardation. aPL can also directly target tissues of the placenta, blocking their growth and development.

What causes antiphospholipid syndrome (causes)?

Why patients develop antiphospholipid autoantibodies (aPLs) is not entirely clear. The production of these autoantibodies is likely triggered by an environmental factor such as infection, occurring in a person with a genetic background that makes a man or woman more susceptible to disease.

Antiphospholipid autoantibodies may be present in the bloodstream for a long time, but thrombotic events occur only rarely. aPL increases the risk of blood clotting, but thrombosis usually occurs when other conditions are present, clotting, such as prolonged inactivity (such as bed rest), surgery, or pregnancy.

Additional risk factors for thrombosis are hypertension, obesity, smoking, atherosclerosis (hardening of the arteries), estrogen use (birth control pills) and associated systemic autoimmune disease (mainly SLE or SLE-like diseases).

How is antiphospholipid syndrome diagnosed?

The diagnosis of antiphospholipid syndrome is made by blood test patients with blood clots and / or repeated miscarriages for the presence of antiphospholipid autoantibodies (aPL). The survey is carried out using three types of analysis. Analyzes may vary due to differences in aPL.

Each individual assay cannot detect all possible autoantibodies, so their use together is highly recommended. At least one of these tests must be positive and confirmed on two occasions with an interval of at least three months.

In general, the higher the test score and the more positive tests, the higher the risk of developing symptoms. Only positive blood tests in the absence of a thrombus, the diagnosis of antiphospholipid syndrome is not a fact.

How is antiphospholipid syndrome treated?

Most often, antiphospholipid autoantibodies are detected after blood clots or repeated miscarriages. Hence, the main goal of therapy is to prevent relapse because the presence of antibodies puts the patient at serious risk for future episodes.

Vascular problems

Acute thrombotic events are treated anticoagulants (blood thinners) first intravenous heparin, and then oral warfarin (Coumadin). In serious situations, some patients are also given compounds that quickly dissolve clots in arteries and veins.

Patients with aPL need to take anticoagulants to avoid recurrent thrombus in the vessels, possibly for several years. In arterial events, relapses are also prevented with drugs that inhibit platelets, such as aspirin and clopidogrel (plavix).

Problems associated with pregnancy

Subcutaneous heparin injections and low-dose aspirin are standard therapy for preventing miscarriage. Therapy begins early in pregnancy and continues immediately after delivery. This therapeutic approach has been shown to be effective in most cases. In refractory cases, adjunctive therapy such as intravenous infusion of immunoglobulin and administration of corticosteroids (prednisone).

Pregnant women who have previously had blood clots in their vessels may receive the same combination heparin and low-dose aspirin - however with higher doses of heparin - due to the increased risk of formation blood clots. Heparin and aspirin therapy has been shown to be safe for both mother and baby.

When antibodies are found in patients without prior thrombotic problems or miscarriages, the need for prophylactic therapy should be assessed on a case-by-case basis. However, it is generally accepted that treatment is not necessary if there are no additional risk factors for vascular occlusion or associated systemic autoimmune disease (eg, lupus).

Living with antiphospholipid syndrome

The need for long-term oral anticoagulant (blood thinning) therapy significantly affects the lifestyle of patients, creating the need for regular monitoring of the anticoagulant (blood thinning) effect and special attention paid to diet and the risks of severe bleeding.

The use of new oral anticoagulants that do not require regular patient testing is being evaluated in ongoing clinical trials. Treatment for common risk factors for thrombosis (diabetes, high blood pressure, high cholesterol, obesity, and smoking) is a must for patients with antiphospholipid syndrome.

Estrogen therapy for birth control or menopause symptoms should generally be avoided with few exceptions in patients with a low risk profile, which should be assessed on a case-by-case basis case.

The current treatment for the prevention of obstetric manifestations is quite effective. Most women can have healthy children. Although antiphospholipid syndrome is an autoimmune disease, its diagnosis does not mean that the patient will develop another autoimmune disease.