Intravenous immunoglobulins and antiphospholipid syndrome: How, when and why? A review of the literature

The antiphospholipid syndrome (APS) is defined by the occurrence of venous and arterial thromboses and recurrent fetal losses, frequently accompanied by a moderate thrombocytopenia, in the presence of antiphospholipid antibodies (aPL), namely lupus anticoagulant (LA), anticardiolipin antibodies (aCL), or anti-β2 glycoprotein-I (β2GPI) antibodies. The current mainstay of treatment for thrombotic APS is heparin followed by long-term anticoagulation, while in obstetric APS, the accepted first-line treatment consists in low-dose aspirin (LDA) plus prophylactic unfractionated or low-molecular-weight heparin (LMWH). Recently, new emerging treatment modalities, including intravenous immunoglobulins (IVIG), have been implemented to manage APS refractory to conventional therapy. The objective of this review is to summarize the currently available information on the IVIG therapy in APS, focusing on the use of IVIG in the obstetric form, CAPS and on primary or secondary thromboprophylaxis. We analyzed 35 studies, reporting the effects of IVIG in APS patients, and we discussed their results. IVIG in obstetric APS seem to be very useful in selected situations (patients not responsive to the conventional treatment, concomitant autoimmune manifestations or infections or patients in whom anticoagulation is contraindicated). IVIG treatment represents an important component of the combination therapy of CAPS and they could be useful, in addition to the standard therapy, to prevent recurrent thrombosis in APS patients refractory to conventional anticoagulant treatment. Anyway, in some cases we also found controversial results that claim the need of further well-designed studies to definitely state the efficacy and tolerability of IVIG in CAPS, obstetric and non-APS.