Antiphospholipid Antibody Syndrome (APAS)

What is Antiphospholipid Antibody Syndrome?

Antiphospholipid Antibody Syndrome is a group of clinical manifestations associated with the presence of high levels of antibodies - antiphospholipid antibodies (APA) in the blood of the affected individual. It is associated with recurrent thromboses (formation of blood clots) in the venous or arterial circulation. There are a number of classifcations of APAS:1. primary: no associated disorder2. secondary: those clearly exhibiting features of an autoimmune disease such as systemic lupus erythematosus (SLE)3. catastrophic: formation of many thrombi in multiple locations in a short space of time.

Statistics on Antiphospholipid Antibody Syndrome?

Unknown. APA may be found in the blood of up to 50% of people affected by systemic lupus erythematosus. However these antibodies have also been found in 5-15 of apparently normal individuals. There does not appear to be any racial predisposition for primary APAS, however it appears to be more common in young-middle aged adults.

Risk Factors for Antiphospholipid Antibody Syndrome

As APA have been found in apparently normal individuals it seems that they are necessary, but not sufficient in themselves to cause the clinical manifestations of antiphospholipid syndrome. It is suggested that triggering factors are involved, for instance various infections, or medications. A genetic association also seems likely.

How is Antiphospholipid Antibody Syndrome Diagnosed?

Normally blood tests are performed looking for abnormalities in the blood. CT scans and MRI are useful in identifying past strokes or heart attacks. Doppler studies are used to identify deep vein thrombosis (DVT).

Prognosis of Antiphospholipid Antibody Syndrome

People with APAS are at increased risk from an early age of death or disability caused by stroke, heart attack, pulmonary embolism and renal failure. However, they are usually able to lead normal and rewarding lives with appropriate treatment. The presence of an underlying autoimmune disease such as SLE also affects outcome.

How is Antiphospholipid Antibody Syndrome Treated?

Occasionally patients are very ill and may require hospitalisation. Usually they can be treated as outpatients. A variety of specialists may be involved in the care of one patient. It is desirable to limit other factors which increase the tendency of the blood to coagulate, including quitting smoking, ceasing the oral controceptive pill and controlling blood pressure. If a patient has developed thromboses in the past, they may need to take long term anticoagulant medication such as warfarin. Patients who are pregnant need to be treated and monitored carefully throughout pregnancy due to the risk of developing complications.

Antiphospholipid Antibody Syndrome References

[1] Carsons, Belilos. Antiphospholipid syndrome. Emedicine (2004)[2] Cervera R. Coronary and valvular syndromes and antiphospholipid antibodies. Thrombosis Research (2004)[3] Editorial: Antiphospholipid antibodies: immunological aspects. Clinical Immunology (2004)112: 127-128.[4] Editorial: Antiphospholipid antibodies: recent progress on their origin and pathogenicity. Joint Bone Spine (2004) 71: 172-174[5] Harris, Pierangeli. Primary, Secondary, Catastrophic Antiphospolipid syndrome: is there a difference? Thrombosis Research (2004)[6] Robbins, Pathological Basis of disease, 6th ed. (1999) W.B Saunders. p 126, 986.