High dose intravenous immunoglobulin in autoimmune rheumatic disorders

Since the effectiveness of high dose intravenous immunoglobulin (IVIg) was first demonstrated in autoimmune thrombocytopenia, IVIg has been investigated in the treatment of various autoimmune rheumatic disorders. Controlled randomised studies have established the efficacy of IVIg in Kawasaki's syndrome, for which combined IVIg and aspirin (acetylsalicylic acid) now constitutes the standard treatment. Another controlled study has demonstrated the benefit of IVIg in dermatomyositis. IVIg treatment in juvenile rheumatoid arthritis has produced contradictory results. Uncontrolled studies and case reports on the application of IVIg in systemic lupus erythematosus, ANCA-associated vasculitides and adult rheumatoid arthritis generally describe short term positive effects. Various mechanisms are thought to underlie the effect of IVIg on autoimmune rheumatic diseases, such as: (i) blockade of Fc receptorsr (ii) immunomodulation via anti-idiotypic interactions: (iii) inhibition of complement-mediated tissue damage; (iv) modulation of cytokine expression by leucocytes and endothelial cells; and (v) inhibition of superantigen-mediated T cell activation. IVIg is considered to be a low-risk form of treatment. Reported adverse effects include headache, aseptic meningitis and transient impairment of renal function. Haemolysis and anaphylactic reactions are rare. The effect profile of IVIg makes it a relevant, although still experimental, form of treatment in autoimmune rheumatic disorders, but its high cost renders it unsuitable as a first-line treatment. Because IVIg does not weaken patients' resistance to infection, it might serve as a therapeutic option in bridging clinical situations where immunosuppressive or cytotoxic approaches are contraindicated in patients with autoimmune disorders, such as intercurrent infection or in the period immediately before and after surgery.