Clinical features, diagnosis, and management of the antiphospholipid syndrome

Almost 30 years after it was first described as a discrete clinical entity, the antiphospholipid syndrome (APS) remains a challenge for clinicians in a wide range of specialities. There remain ongoing issues regarding nomenclature, the expanding range of clinical manifestations, and management of certain APS patient subgroups. In addition to the presence of appropriate clinical features, the diagnosis of APS also fundamentally requires the finding of positive antiphospholipid antibody test result(s), and unfortunately much still has to be done to improve the robustness, reproducibility, and standardization of these assays. This article discusses ongoing dilemmas and issues related to clinical aspects of APS including (i) the derivation of the current nomenclature and the implications of recent proposals for its revision; (ii) the problems that the protean clinical manifestations pose for many clinicians, in particular those not intimately familiar with APS; (iii) the potential pitfalls of applying the APS classification criteria as diagnostic criteria (although no doubt tempting for nonspecialist clinicians); (iv) the concept of seronegative APS and the effect that recent proposed changes in antiphospholipid antibody testing strategies may have on this diagnosis; and finally (v) an overview of key developments in the clinical management of APS patients over the past 30 years.