Clinical features and mid-term follow-up in infants younger than 3 months with Kawasaki disease in a Chinese population.

AIM: To explore the clinical features and mid-term follow-up of Kawasaki disease (KD) in infants younger than 3 months of age in a Chinese population.

METHODS: We performed a retrospective analysis of clinical signs, laboratory data, echocardiography results and outcomes for patients with KD diagnosed at our hospital from January 2009 to December 2013. A total of 1150 children were diagnosed with KD, and 200 KD patients were enrolled in this study. Group 1 included 40 children younger than 3 months of age. We randomly selected a control group as Group 2 included 160 children older than 3 months of age who fulfilled diagnostic criteria for KD and maintained follow-up for more than 1 year.

RESULTS: There was a significant difference in clinical manifestations between the two groups, except respiratory infection. Group 1 was more likely to have incomplete presentation (P < 0.001). There were no significant differences in laboratory data except for white blood cell counts between the two groups. Coronary artery abnormalities were significantly different between the two groups (P < 0.001). At a mean follow-up of 18 months (range 12-48 months), all patients with coronary artery abnormalities, except for giant coronary aneurysms, returned to normal in terms of diameter as assessed by echocardiography.

CONCLUSIONS: Infants younger than 3 months of age with KD often present with incomplete criteria, and diagnosis may be delayed. In addition, there may be a higher risk of developing coronary artery abnormalities. All patients except those with giant coronary aneurysms recovered well without complications at mid-term follow-up.