CLASSICAL PATHWAY COMPLEMENT ACTIVATION IN KAWASAKI SYNDROME

In this study the complement breakdown products C3d, C4d, Bb and membr ane attack complex were measured in plasma of patients with Kawasaki s yndrome. The results suggested strong activation of the classical acti vation pathway. However, there was no significant decrease in hemolyti c titer or in the concentrations of the intact proteins C3, C4, and B. The relationship between the serum concentrations of cytokines and co mplement components was examined; increased interleukin-6 concentratio n on the fifth day after the onset of fever was found to correlate wel l with the C3 and B concentrations in serum obtained 5 days later We c onclude that complement activation occurred in Kawasaki syndrome via t he classical pathway but that the inflammatory reaction was accompanie d by increased production of complement components. As a result, there was increased formation of activation products without changes in the serum complement levels.