Antiphospholipid antibody levels in intravenous immunoglobulin (IVIg) preparations.

The antiphospholipid syndrome (APS) is characterized by various clinical manifestations and by elevated levels of antiphospholipid antibodies. Passive induction of APS by infusion of these antibodies has been demonstrated in animal models. Intravenous immunoglobulin (IVIg) is one of the therapeutic options in APS. In this study, five commercially used preparations of IVIg were tested for the presence of elevated levels of cardiolipin, beta-glycoprotein-I, phosphatidylserine, antinuclear, and double-stranded DNA autoantibodies, as well as for lupus anticoagulant activity. The absence of abnormal elevated levels of any of these autoantibodies in five different IVIg preparations provides additional evidence for the safety of IVIg use in APS.