The immunologic effects of IVIG in Kawasaki disease.

Kawasaki disease (KD) is an acute febrile illness of early childhood that is associated with the development of coronary artery aneurysms in 15-25% of the cases. The acute phase of KD is characterized by a deficiency of suppressor T cells, marked activation of the immune system and increased secretion of cytokines by immune effector cells. Evidence that this immune activation contributes to the vascular endothelial cell damage in KD is suggested by the observation that patients in the acute phase of KD have circulating antibodies lytic for vascular endothelial cells activated with gamma interferon, IL-1 or tumor necrosis factor. In contrast, sera from these patients do not lyse unstimulated endothelial cells. High dose intravenous gammaglobulin (IVGG) treatment is effective in preventing the occurrence of coronary artery abnormalities in KD. Patients treated with IVGG have a significant increase in T suppressor cells, a decrease in circulating activated T helper cells, and a decrease in spontaneous IgG and IgM synthesis. These observations suggest that IVGG reduces the vasculitis in KD by suppressing the marked immune activation associated with this disease.