Study design

Design Randomised, open-label trial.

Allocation Age-stratified, computer-generated randomisation.

Blinding Patients/guardians and physicians were not blinded, but the cardiologists performing the echocardiograms were blinded to treatment allocation.

Study question

Setting Multicentre study (74 hospitals in Japan).

Patients 248 children with Kawasaki disease (KD) who had a risk score of 5 points or higher (based on a composite score that included points for duration of fever, age, hyponatraemia, AST and CRP concentration, neutrophil percentage, platelet count). Excluded were: children with a history of previous KD, and those who recently received steroid or intravenous immunoglobulin (IVIG) treatment, had a suspected infectious disease, or were diagnosed after 9 days of illness.

Intervention Participants were allocated to receive IVIG plus prednisolone (n=125) or IVIG alone (n=123). Additional ‘rescue’ treatment was allowed for patients with fever for more than 24 h or relapse. Six participants were excluded from the final analysis (intention to treat), which included data from 121 patients in each group.

Outcomes Primary endpoints were the absolute diameter of coronary arteries and the Z score of coronary artery (CA) diameters at weeks 1, 2 and 4. Secondary endpoints were the proportion needing additional rescue treatment, the duration of fever after enrolment, and CRP concentrations at 1 and 2 weeks.

Follow-up period Four …