Diagnosis and management of the antiphospholipid syndrome

#### Summary points Antiphospholipid syndrome was first described 27 years ago in patients with systemic lupus erythematosus (SLE) and positive anticardiolipin antibodies, who presented with a clotting syndrome that affected arteries and veins.1 Female patients had a high risk of recurrent miscarriage and late fetal loss. The international classification criteria for this syndrome used today are based on those initial clinical observations.2 The syndrome is under-recognised and underdiagnosed and can have devastating consequences if untreated, mainly because of uncontrolled thrombosis. Difficulties in diagnosis are compounded by a lack of standardisation of diagnostic tests. Early recognition is crucial, because treatment can reduce mortality and morbidity in relatively young people who often present with diseases such as stroke, myocardial infarction, and deep vein thrombosis. Because of its variable clinical presentation, patients with antiphospholipid syndrome present to a variety of medical practitioners. Here, we introduce this complicated and intriguing syndrome, and provide basic guiding principles for the recognition, diagnosis, and management of affected patients. #### Sources and selection criteria We searched the following databases for evidence from systematic reviews, clinical trials, and prospective cohort studies: PubMed (1949 to January 2010), Embase (1980 to January 2010), Web of Science (1945 to January 2010), Cochrane Library (1990 to January 2010), CINAHL (1982 to January 2010), and Academic Search Premier (1865 to January 2010). All relevant keyword variations were used. In general, the …