Classification criteria for antiphospholipid syndrome.

The major purpose of the 1999 international consensus criteria for definite antiphospholipid syndrome (APS) is to facilitate the selection of uniform groups of patients for clinical and experimental studies. An early evaluation suggests that the criteria fulfill this purpose when tested in patients with systemic lupus erythematosus or lupus-like diseases. The criteria will likely need modification as investigators appraise and reach consensus about new information on APS. The international APS symposium has had an important role in this process and provides a mechanism for facilitating future advances in this subject.