Effects of early steroid reduction in initial combination therapy for Kawasaki disease

In recent years, the use of steroids as an initial adjunctive therapy for patients with Kawasaki disease (KD) at high risk of being unresponsive to intravenous immunoglobulin (IVIG) has shown promising outcomes. However, the optimal duration and tapering method of steroid therapy have not been thoroughly investigated. While the Randomized controlled trial to Assess Immunoglobulin plus Steroid Efficacy study, which followed the most prominent protocol in Japan, tapers and discontinues steroids for >15 days, our institution reduces and discontinues steroids over six days once inflammation is adequately controlled. In this study, we aimed to determine the effects of our protocol of steroid tapering in initial combination therapy for KD.

The medical records of 359 patients newly diagnosed with KD admitted to our institute between June 2016 and September 2023 were retrospectively reviewed. Among them, 120 patients were classified as being at high risk of IVIG non-response, and 104 patients who met the inclusion criteria were analysed.

Of the 104 patients, 23 (22.1%) experienced a recurrence of KD symptoms. Of these, only one patient (1.0% of the total) exhibited symptom recurrence after steroid tapering. One month after the onset of KD, coronary artery lesions were observed in two patients (2.0%), both of whom had small transient coronary artery aneurysms.

In cases in which the inflammatory response has been adequately controlled, it may be possible to taper steroid therapy faster than stated in previous studies without compromising treatment outcomes.