To evaluate endothelial function in children within 5 years after the onset of Kawasaki disease (KD).

A total of 46 children were enrolled prospectively as follows: 9 patients with KD and coronary artery lesions composed group 1, 15 patients with KD but without coronary artery lesions composed group 2, and 22 healthy age- and sex-matched children composed group 3. Flow-mediated dilatation (FMD) of the brachial artery, intima-media thickness of the common carotid artery, and biologic characteristics were compared among the 3 groups. Differences in the factors associated with endothelial function after KD were examined as well.

The mean age of the study group was 6.5 ± 1.7 years. The patients with KD were studied at a median interval of 3.3 years (IQR, 2.0-4.4 years) from the onset of disease. The percent FMD (%FMD) was significantly lower in group 1 patients (median, 4.4%; IQR, 2.6%-5.7%) compared with both group 2 (median, 9.1%; IQR 6.6%-10.7%; P < .01) and group 3 (median, 11.1%; IQR, 10.1%-13.9%, P < .01). The %FMD was statistically significantly lower in group 2 compared with group 3 (P < .05). There were no significant differences in the intima-media thickness among the 3 groups. There was a significant negative correlation between %FMD and the total duration of fever (r = −0.50; P = .013).

The children with KD already had arterial endothelial dysfunction within 5 years after the onset of illness. The longer the duration of fever, the greater the risk of inflammation-induced endothelial dysfunction.