Antiphospholipid Syndrome

What is Antiphospholipid Syndrome?

Antiphospholipid Syndrome is caused by a phospholipid (fos"fo-LIP'id) which is a fat (lipid) that contains phosphorous. It undergoes hydrolysis (hi-DROL'ih-sis), which means it splits into fatty acids, glycerin and a nitrogen compound when water is added. The antiphospholipid (an"tih-fos"fo-LIP'id) syndrome (APLS) is defined by:

antiphospholipid antibodies and blood clots forming in blood vessels;

recurrent pregnancy loss, or;

a decrease in the number of blood platelets.

Statistics on Antiphospholipid Syndrome?

Actual frequency in the general population is unknown. aPL antibodies can be found in as many as 50% of individuals with systemic Lupus Erythematosus and in 1-5% of the healthy population. On the other hand, aCL antibody tends to occur more frequently in elderly individuals. Recent literature suggests that the occurrence rate of APS in patients with Systemic Lupus Erythematosus is 34-42%. In a study of 100 patients with verified venous thrombosis and no history of Systemic Lupus Erythematosus, 24% had aCL antibody and 4% had LA.

Risk Factors for Antiphospholipid Syndrome

This syndrome can occur by itself (primary). It can also be caused by an underlying condition (secondary). About a third of patients with primary APLS have heart valve abnormalities. Valve lesions associated with APLS occur as masses (nonbacterial vegetations) or thickening. Both masses and thickening can affect how well valves work, although valve problems are much more common with thickening. The main problem is regurgitation -- blood leaking backward through the valves. The mitral valve is most often affected, followed by the aortic valve.

Progression of Antiphospholipid Syndrome

Most individuals with primary APS lead normal healthy lives with appropriate medication and lifestyle modifications. However, subsets of patients continue to have thrombotic events despite aggressive therapies. For these patients, the disease course can be devastating, often leading to significant morbidity or early mortality.Patients with secondary APS carry a similar prognosis; however, morbidity and mortality may also be influenced by their underlying autoimmune or rheumatic condition.

How is Antiphospholipid Syndrome Diagnosed?

Patients with the antiphospholipid syndrome can have a variety of antibodies to phospholipids in their blood, including VDRL/RPR (a syphilis test that can be falsely positive in these patients), lupus anticoagulant, prolonged PTT, and cardiolipin antibody. As mentioned above, the anticardiolipin antibody has also been found in patients with the immune disease, systemic lupus erythematosus, which is characterized by the production of a variety of abnormal antibodies.

Prognosis of Antiphospholipid Syndrome

How is Antiphospholipid Syndrome Treated?

The treatment of patients with anticardiolipin syndrome has substantially evolved since they were discovered to be clinically important in the mid-1980s. Each manifestation of the antiphospholipid syndrome, and each individual patient with the condition, is treated uniquely.Because many of the features of illness with anticardiolipin syndrome are associated with an abnormal grouping of normal blood clotting elements (platelets), treatment is often directed toward preventing clotting by thinning the blood. Patients with this disorder have an abnormal tendency to form blood clots (thrombosis). The abnormal blood clotting can affect the function of virtually any organ. Medications that thin (anticoagulate) the blood, such as heparin and coumadin (powerful blood thinners), are used for treatment. Aspirin has an affect on platelets which inhibits their grouping (aggregation) and has also been used in low doses to thin the blood of selected patients. Cortisone-related medications, such as prednisone, have been used to suppress the immune activity and inflammation in patients with certain features of the condition. For patients suffering from systemic lupus erythematosus who also have anticardiolipin syndrome, hydroxychloroquine (Plaquenil) has been reported to add some protection against blood clotting.

Antiphospholipid Syndrome References

[1] American Heart Association[2] eMedicine[3] Petri M: Antiphospholipid antibody syndrome: an acquired cause of venous and arterial hypercoagulability. Mt Sinai J Med 1997 Nov; 64(6): 376-82[Medline]. [4] Petri M: Pathogenesis and treatment of the antiphospholipid antibody syndrome. Med Clin North Am 1997 Jan; 81(1): 151-77[Medline]. [5] Pittoni V, Isenberg D: Apoptosis and antiphospholipid antibodies. Semin Arthritis Rheum 1998 Dec; 28(3): 163-78