Background Currently, the classification of APS is based on clinical and laboratory criteria originally published in 1999 (Sapporo classification)  and updated in 2006 .
Objectives To assess the need for new APS classification criteria.
Methods Based on the Task Force (TF) reports of the 14th International Congress on Antiphospholipid Antibodies (aPL) (September 2013, Rio de Janeiro, Brazil), a new Task Force on “APS Diagnostic and Classification Criteria” has been created under the auspices of the 15th International Congress on aPL (September 2016, Istanbul, Turkey). Members were selected based on their roles as chairs of previous TFs or interested scientific planning committee members. The chairs of this new TF designed a 14-question needs-assessment survey, which was emailed to 13 members in August 2014. Responses were analyzed anonymously in a descriptive fashion.
Results Survey response rate was 100%. 92% of survey participants reported the need for new ACR classification criteria; 100% agreed that all disease domains are not sampled by current criteria, particularly related to non-criteria APS manifestations; 85% reported scenarios in which current criteria disagree with expert diagnoses; and 62% agreed that other aPL tests should be part of the criteria. Scenarios in which expert diagnoses disagreed with current criteria included: 1) patients with non-criteria manifestations only (with or without positive aPL tests); 2) non-criteria obstetrical findings in patient with positive aPL tests; 3) high suspicion for APS in patients with lack of “persistence” of aPL tests, or negative to low titer aPL tests. Major limitations of the current criteria reported by the responders included: 1) no inclusion of non-criteria clinical manifestations and aPL tests; 2) no evidence based pregnancy morbidity definition; 3) no risk stratification based on aPL-profiles and other co-morbidities; and 4) unclear definition of aPL “persistence”.
Conclusions Broad consensus exists among surveyed international APS physician scientists regarding the need for new APS classification criteria. Based on these findings, the Task Force on APS Diagnostic and Classification Criteria is spearheading an effort to prepare new APS Classification Criteria.
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Disclosure of Interest M. Barbhaiya: None declared, M. Abreu: None declared, M. Amigo: None declared, T. Avcin: None declared, M. Bertolaccini: None declared, W. Branch: None declared, P. de Groot Grant/research support from: Thrombosestichting, the Netherlands, Consultant for: SynapseBV, Maastricht, the Netherlands, G. de Jesus: None declared, R. Levy: None declared, M. Lockshin: None declared, M. Tektonidou: None declared, D. Wahl: None declared, R. Willis Employee of: Louisville APL DIagnostic Inc., S. Zuily: None declared, K. Costenbader: None declared, D. Erkan: None declared