Abstract 12339: Aggressive Additional Treatment Strategies to Eliminate Coronary Artery Aneurysms in Treatment-Resistant Kawasaki Disease

Introduction: Kawasaki disease (KD), which is the most common multisystem vasculitis with unknown causes in childhood, causes coronary artery aneurysms (CAAs) especially in treatment-resistant cases. Even with steroid combination therapy, sometimes the fever may persist or recur and requires several additional treatments, which cause CAAs. We reported previously about the scoring systems to predict non-responders to the initial steroid combination therapy. The aim of this study is to prove whether aggressive additional treatment strategies can prevent CAAs in patients at high risk of resistance to initial steroid combination therapy. Methods: The subjects were 39 KD patients with high scores in the scoring systems to predict non-responders to the initial steroid combination therapy*. *Patients who had high scores in all three predictive scoring systems in Japan, and scored 3 points or more in the following scoring system: Kobayashi scores ≥7, 2 points; Egami scores ≥4, 1 point; Number of neutrophils after initial treatment≥ 12000/μL, 2 points* Group 1 (n=26) received additional treatment after recurrent fever (ordinary strategy), Group 2 (n=13) received additional treatment before recurrent fever (aggressive strategy). We compared the incidence of CAAs (including transient dilatation) in each group. Results: In Group 1, there were 15 non-responders (58%) to the initial steroid combination therapy, compared to 0 in Group 2 (p<0.01). All of them had recurrent fever after resolving the fever once. The median day of recurrent fever was day 6 [5.3-7]. In Group 1, there were 5 patients (19%) who had coronary artery dilation greater than z-score >2.5 by treatment resistance, compared to 0 in Group 2 (p<0.01). Conclusions: The aggressive additional treatment strategies (intervention before recurrent fever) prevent CAAs in patients at high risk of resistance to initial steroid combination therapy. Even if the fever is relieved once in the initial treatment, it seems important to prevent recurrent fever around day 7 when histological changes begin in high-risk patients.