Objective: To determine the incidence of Kawasaki disease (KD) in Northern France by using new American Heart Association (AHA) criteria.
Study design: A 1-year prospective multicenter cohort study was performed in all pediatric departments. Patients <18 years old, who were admitted for prolonged but initially unexplained fever or suspected KD were included. All patients received the standard treatment considered appropriate by their physicians. A descriptive analysis and comparison of patients with complete and incomplete forms of KD were performed. The incidence of confirmed cases of KD (complete and incomplete forms) was calculated.
Results: Seventy-seven children were included (39 in whom KD was diagnosed). Of the patients with KD, 26 (67%) met the classic AHA case definition, and 7 (18%) had incomplete KD. Cardiac ultrasound scanning was helpful in the diagnosis of 6 of 7 patients with incomplete KD (86%). The final incidence of confirmed KD was 9 of 100,000 children <5 years of age. In 6 children (15%) the diagnosis of KD was uncertain, but they were successfully treated for it. Coronary disease was identified in 48% of patients with confirmed KD.
Conclusion: The incidence of KD is higher than previously reported, in part because earlier reports did not include incomplete forms. New AHA criteria (laboratory tests and early echocardiography) were helpful for the diagnosis of incomplete forms of KD.