Kawasaki disease is the main form of vasculitis responding to IVIG, in combination with high dose aspirin. ANCA vasculitis will respond temporarily, and this can be useful if patients are also septic, because it is an immunomodulating therapy. Check serum IgA to avoid allergic reactions in patients who are IgA deficient (because there is usually some IgA contamination). IVIG is prepared form pooled human serum, typically from thousands of donors. Viral screening of IVIG is now highly effective (previous IVIG therapy use has been associated with hepatitis C transmission). This evidence concerns the gene CD79A and hepatitis C virus infection.