Do patients followed in anticoagulation clinics for antiphospholipid syndrome meet criteria for the disorder?
Although specific criteria for diagnosing the antiphospholipid syndrome (APS) exist (the Sapporo Criteria), most physicians are not aware these include repeat testing and documentation of either a lupus anticoagulant or medium to high levels of anti-cardiolipin antibody. Incorrect diagnosis of APS may result in unnecessary long-term anticoagulation. The purpose of this study was to determine the clinical and serological characteristics of patients being treated for APS and concordance with published criteria. This cross-sectional study identified APS patients who were being treated with warfarin at one of three university-based anticoagulation clinics. Levels of anticardiolipin antibody were classified as low-positive if abnormal but < 40 GPL/MPL units and medium/high-positive if > or = 40 units. Strength of meeting Sapporo criteria was graded as definite, possible, and not meeting criteria. Of 103 cases, 97 had clinical and laboratory data available. Only 10 cases (10%, 95% Confidence
