Backgroud: Diagnosis of Kawasaki disease (KD) is based on 5 clinical features. Incomplete KD (IKD) with a fewer features is more common in infants and older children, in whom the rate of coronary artery aneurysms is paradoxically higher. This study was designed to evaluate between the age at diagnosis and the risk factors on coronary arterial lesions (CAL) in patients with IKD.
Methods: Data from 396 patients with KD in single center were collected from January 2003 to July 2007 retrospectively. Patients were grouped according to their age at diagnosis; Group A (<1 year of age), Group B (1≤age<5 years of age), and Group C (≥5 years of age).
Results: In total of 396 patients with KD, 87 (22.0%) patients were in Group A, 246 (62.1%) in Group B, and 63 (15.9%) in Group C. In groups A and C, days to start intravenous immunoglobulin (IVIG) were longer than Group B. There were no differences in the incidence of IKD, the late CAL, and the rate of IVIG retreatment among three groups. In 174 patients with IKD, there were no differences in the late incidence of CAL and IVIG retreatment according to different age groups either. Compared with typical KD, the febrile duration and days to start IVIG were longer, and the rate of IVIG retreatment was higher in IKD, but there was no difference in the risk of CAL between the typical and IKD.
Conclusions: Recently in the management of KD, especially the incomplete type, the age at KD diagnosis may be no more significant to determine the development of CAL.