Is testing for antiphosphatidylethanolamine antibodies clinically useful?

One of the most intriguing characteristics of the antiphospholipid syndrome (APS) is that diagnosis requires the combined presence of clinical abnormalities (thrombosis and/or miscarriages) and at least one of the following antiphospholipid antibodies: lupus anticoagulant, anticardiolipin, or anti–β2-glycoprotein I. Clinicians occasionally have difficulty making this diagnosis in patients with a clinical picture of APS but without any of the previously mentioned antiphospholipid antibodies. Such a status has been defined as "seronegative APS." Under these conditions, antiphosphatidylethanolamine antibodies deserve particular attention, as they have been described as being associated with the main clinical events of APS. Thus, this review focuses on issues related to the characteristics of antiphosphatidylethanolamine antibodies, including the nature of antigen targets and their role in homeostasis, the methodologic problems encountered in their detection, and their clinical associations.