The Clinical Utility and Safety of a New Strategy for the Treatment of Refractory Kawasaki Disease

To assess the clinical utility and safety of a strategy for refractory Kawasaki disease, defined by Egami score ≥3. First-line treatment was with intravenous methylprednisolone (30 mg/kg, 2 hours, 1 dose) plus intravenous immunoglobulin (2 g/kg, 24 hours) treatment. Patients resistant to first-line treatment received additional intravenous immunoglobulin as a second-line treatment. Patients resistant to second-line treatment who had received Bacillus Calmette-Guérin vaccination 6 months earlier were treated with infliximab; otherwise, plasma exchange was performed. A total of 71 refractory patients with Kawasaki disease (median age: 2.4 years) of 365 patients with Kawasaki disease were treated according to our strategy from April 2007 to April 2016. Treatment resistance was defined as a persistent fever at 36 hours after treatment. We evaluated coronary artery lesions at the time of the diagnosis, at 1 month, and at 1 year after the diagnosis in accordance with the American Heart Association guidelines and the criteria of the Japanese Ministry of Health, Labour, and Welfare. First-line therapy was effective for 58 of 71 patients (81.6%), and second-line therapy was effective for 9 of 13 patients (69.2%). At third line, 3 patients were treated by infliximab, and 1 was treated with plasma exchange. Of the 18 patients with coronary artery abnormalities at diagnosis, 13 patients at 1 month and 6 patients at 1 year had coronary artery dilatation (median z score 3.0, 2.6, and 1.4, respectively). There were no patients with coronary artery aneurysm (CAA). Our strategy for refractory Kawasaki disease was safe and effective in preventing CAA.