Clinical Characteristics of Kawasaki Disease in Infants Younger than Six Months: A Single-Center Study.

BACKGROUND AND OBJECTIVES

Kawasaki disease (KD) is the leading cause of acquired heart disease, which predominantly occurs in children under the age of 5 years. However, there are fewer cases of KD in infants younger than 6 months, which makes it difficult to diagnose. We investigated the clinical manifestations of KD in this age group and compared them with those in the older age group.

SUBJECTS AND METHODS

We retrospectively reviewed the medical records of 239 patients with KD admitted to the Hallym Sacred Heart Hospital from January 2013 to June 2015. The data were categorized into 2 groups by age: Group A (≤6 months, n=26) and Group B (>6 months, n=213).

RESULTS

Group A had a longer hospitalization period than Group B (6.69 vs. 5.19 days, p=0.002). Group A had fewer clinical manifestations upon admission, due to which there was a higher incidence of incomplete KD (1.88 vs. 3.54 of the diagnostic criteria, p<0.05; and 19.2% vs. 4.2% incomplete KD incidence, p=0.002). The rate of cardiac complications was higher in Group A (30.8% vs. 11.7%, p=0.011).

CONCLUSION

The rate of cardiac complications of the patients younger than 6 months was significantly higher than that of the older patients. Therefore, infants younger than 6 months with unexplained fever for more than 5 days should be suspected as having KD, even if the principal clinical features are not fully presented. Echocardiography must be appropriately used for diagnosis of KD in suspected patients.