Task force report on non-criteria manifestations: Thrombocytopenia

Thrombotic manifestations, particularly when recurrent, are the antiphospholipid syndrome’s (APS) seal of identity. However, in a recent analysis comprising over 2,900 APS patients, the frequency of thrombocytopenia ranged from 30% to 46%. Accumulated data have also shown that between 10–15% of patients with immune thrombocytopenic purpura (ITP) may develop thrombosis depending upon their antiphospholipid antibody (aPL) profile. These statements could mean that these two apparent different settings are one and the same: “ITP” patients with positive aPL and patients with thrombocytopenia as their only APS clinical manifestation. What appears to define these “two” settings is the presence of aPL with lupus anticoagulant activity. Regardless of this evidence, according to the APS Classification criteria, an aPL-positive patient with thrombocytopenia but without a history of thrombosis or pregnancy morbidity is not classified as having APS. Herein, we provide relevant information regarding the pathogenic and clinical similarities and differences of platelet destruction seen in APS and ITP. Finally, we review the current therapeutic decisions in aPL-associated thrombocytopenia based on expert opinion and international consensus report for the management of ITP.