Objective. We investigated whether levels of intercellular adhesion molecule 1 (ICAM-1) antigen shed into the circulation increase during acute Kawasaki disease (KD). We also compared ICAM-1 levels in acute KD with those in anaphylactoid purpura (AP) and in measles.

Methods. Serum ICAM-1 levels were measured by a double-determinant immunoassay using 2 monoclonal antibodies in the FAST (Falcon assay screening test) system. Serum levels of tumor necrosis factor α (TNFα) were measured by a specific and sensitive sandwich enzyme immunoassay.

Results. Patients with KD, but not those with AP or measles, had increased levels of shed ICAM-1 antigen in serum samples obtained during acute stages. Moreover, during the acute stage, KD patients with coronary artery lesions (CAL) had still higher levels of shed ICAM-1 than did those without CAL. We found a positive correlation between serum levels of shed ICAM-1 and levels of TNFα during acute KD.

Conclusion. Our findings suggest that the serum ICAM-1 level is an important immunologic parameter for determining the severity of vascular damage during acute KD.