Journal of Pediatric Cardiology and Cardiac Surgery

Introduction: In Okayama and Hyogo, Yersinia pseudotuberculosis (YPT) infection is present in about 10% of patients with Kawasaki disease (KD). These patients are older and have a higher incidence of re-administration of immunoglobulin (re-IVIG) and higher prevalence of coronary artery aneurysm (CAA) compared to KD patients without YPT infection.

Materials and Methods: The subjects, 208,757 cases reported in the Japanese KD National Survey (1999–2016), were divided into 8 regional groups: region-1; Hokkaido/Tohoku, region-2; Kanto, region-3; Tokyo/Kanagawa, region-4; Chubu, region-5; Kansai, region-6; Hyogo/Okayama, region-7; Chugoku/Shikoku, and region-8; Kyushu/Okinawa. These groups were compared for the age of onset of KD, rate of re-IVIG, and prevalence of CAA with the Kruskal–Wallis and chi-square tests. In addition, the onset age was categorized into 19 groups, and the proportions of patients in each age group were compared among the 8 regions.

Results: In pairwise comparisons with region-6, the age of onset was higher in region-2 (p<0.05) and lower in region-8 (p<0.001), the re-IVIG rate was lower in region-1, 2, and 3 (each p<0.001), and the prevalence of CAA was higher in region-1 (p<0.01). The proportions of patients in each age group differed among regions.

Discussion: There were regional variations in onset age of KD, re-IVIG rate, and CAA prevalence, although they were all averages in region-6. The nationwide incidence of KD associated with YPT infection is desirable to be investigated.