[Immunoregulatory mechanisms of action of intravenous gammaglobulin in Kawasaki syndrome].

Kawasaki Syndrome (KS) is an acute vasculitis in young children associated with the development of coronary artery abnormalities. KS has been reported to occur in over 40 countries including Poland. The etiology of this disease remains controversial. However, recent studies suggest a potential role of bacterial toxins (superantigens) in the immunopathogenesis of KS. Immunomodulatory benefit and potential toxin neutralisation by intravenous immune globulin (IVIG) support the hypothesis of superantigen-related activation of the immune system in KS. The prevalence of cardiovascular abnormalities can be significantly reduced by treating patients during the first 10 days of illness with high-dose of intravenous gammaglobulin. The following predominant and non-exclusive mechanisms of action have been proposed to account for the immunomodulatory effects of IVIG in Kawasaki and other immune-mediated diseases: (i) functional blockade of Fc receptor on monocytes/macrophages; (ii) modulation of the production of cytokines and cytokine antagonists; (iii) inhibition of complement mediated damage; (iv) neutralisation of bacterial toxins by specific antibodies; (v) neutralisation of circulating autoantibodies by complementary (e.g. anti-idiotypic) antibodies in IVIG. These observations provide an important information that early recognition and prompt treatment of this illness is critical for a successful outcome.