Familial antiphospholipid antibodies and acquired circulating anticoagulants.

Familial clustering of elevated antiphospholipid antibody levels has been described, but the reports are heterogeneous with regard to the characterization of the antiphospholipid syndrome (APS), coexisting autoimmune diseases and clinical implications. We report a familial occurrence of APS in two patients, in the presence of SLE in the mother and absence of autoimmune diseases in the daughter along with acquired circulating inhibitors in both cases: platelet inhibitor and factor IX inhibitor, respectively.