title: Assessment of the 2006 revised antiphospholipid syndrome classification criteria.
abstract: OBJECTIVE
  To analyse antiphospholipid (aPL) antibody-positive patients using the 2006 revised antiphospholipid syndrome (APS) classification criteria.
  
  
  METHODS
  A descriptive study of 200 aPL-positive patients identified in a local, hospital-based registry, analysing demographic, clinical and aPL characteristics. Patients were analysed for (1) fulfillment of the 1999 original (Sapporo) and 2006 revised APS classification criteria; (2) non-criteria aPL features (for all aPL-positive patients, based on the 2006 revised criteria definitions); and (3) non-aPL thrombosis risk factors at the time of the clinical events (for patients with APS, based on the 2006 revised criteria stratifications).
  
  
  RESULTS
  Of the 200 patients, 183 patients had sufficient data for analysis. Of these, 39 (21%) patients did not meet the laboratory requirement of the original 1999 criteria. Of 81 patients with APS who met the 1999 classification criteria, 47 (58%) also met the 2006 revised criteria. Of 63 asymptomatic (no vascular or pregnancy events) aPL-positive patients who met the laboratory requirement of the 1999 classification criteria, 38 (60%) also met the laboratory requirement of the 2006 revised criteria. More than 50% of the patients with APS with vascular events had identifiable non-aPL thrombosis risk factors at the time of clinical events.
  
  
  CONCLUSIONS
  Only 59% of the patients meeting the 1999 APS Sapporo classification criteria met the 2006 APS classification criteria. The revised criteria will have positive implications in APS research by way of limiting the inclusion of a heterogeneous group of patients and also by way of providing a risk-stratified approach.
authors.affiliation: Weill Medical College of Cornell University, New York, NY, USA. mala.kaul@duke.edu
authors.forename: Mala
authors.initials: M
authors.lastname: Kaul
authors.forename: Doruk
authors.initials: D
authors.lastname: Erkan
authors.forename: Lisa
authors.initials: L
authors.lastname: Sammaritano
authors.forename: Michael D
authors.initials: MD
authors.lastname: Lockshin
mesh_terms: D017152:Antibodies, Antiphospholipid / Q000097:blood; D016736:Antiphospholipid Syndrome / Q000145:classification / Q000150:complications / Q000276:immunology*; D005260:Female; D006801:Humans; D008297:Male; D011247:Pregnancy; D011248:Pregnancy Complications / Q000276:immunology; D012307:Risk Factors; D013927:Thrombosis / Q000209:etiology / Q000276:immunology
chemical_list: D017152:Antibodies, Antiphospholipid