JPRN‐UMIN000009524.

Trial name or title	A prospective randomised controlled trial of immunoglobulin plus prednisolone for KD patients with high risk for coronary abnormalities
Methods	Parallel, assessor‐blinded study Control group: Intravenous immunoglobulin (2 g/kg) over 24 h with aspirin (30 mg/kg/day). The dosage of aspirin can be reduced to 5 mg/kg/day after resolution of fever Treatment group: Intravenous immunoglobulin (2 g/kg) over 24 h plus intravenous prednisolone (2 mg/kg/day) with aspirin (30 mg/kg/day). The dosage of aspirin can be reduced to 5 mg/kg/day after resolution of fever Prednisolone will be given intravenously for 3 days at least and then can be given orally after resolution of fever. When concentration of C‐reactive protein becomes 1.0 mg/dL or less, the dose of prednisolone will be tapered over 9 days
Participants	Target sample size 240 Inclusion criteria: 1. Severe KD patients of risk score 4 points or more 2. Written informed consent is obtained from patients or their parents 3. Streptococcus, Epstein‐Barr virus, adenovirus, or yersinia infection, or measles, or Stevens‐Johnson syndrome is ruled out Exclusion criteria: 1. Patients with past histories of KD 2. Patients diagnosed as KD on the ninth day of illness or later 3. KD patients with coronary artery lesions before treatment 4. KD patients with defervescence before treatment 5. Patients given steroids within 28 days before treatment 6. Patients given IVIG within 180 days before treatment 7. Patients with severe underlining diseases 8. Patients with a concurrent infection
Interventions	Control group: Intravenous immunoglobulin (2 g/kg) over 24 h with aspirin (30 mg/kg/day). The dosage of aspirin can be reduced to 5 mg/kg/day after resolution of fever Treatment group: Intravenous immunoglobulin (2 g/kg) over 24 h plus intravenous prednisolone (2 mg/kg/day) with aspirin (30 mg/kg/day). The dosage of aspirin can be reduced to 5 mg/kg/day after resolution of fever Prednisolone will be given intravenously for 3 days at least and then can be given orally after resolution of fever. When concentration of C‐reactive protein becomes 1.0 mg/dL or less, the dose of prednisolone will be tapered over 9 days
Outcomes	Primary outcome: Incidence of coronary artery lesions within 4 weeks after primary treatment Secondary outcome: Incidence of coronary artery lesions at 4 weeks after primary treatment, z‐score of coronary artery diameters, incidence of resistance to primary treatment or relapse, duration of fever after primary treatment, serum concentrations of C‐reactive protein at 1 week and 2 weeks after primary treatment, and incidence of adverse events
Starting date	17 December 2012
Contact information	Taichi Kato Nagoya University Graduate School of Medicine Department of Pediatrics 65 Tsuruma‐cho, Showa‐ku, Nagoya 466‐8550, Japan +81‐52‐744‐2298 ktaichi@med.nagoya‐u.ac.jp
Notes

IVIG: Intravenous immunoglobulin