Refractory Kawasaki disease: modified methylprednisolone regimen decreases coronary artery dilatation

The use of corticosteroids in Kawasaki disease (KD) is still controversial. The aim of this study was to investigate the safety and effectiveness of modified methylprednisolone (mPSL) regimen as an initial treatment for refractory KD.

This is a real-world observational study. We identified refractory KD with a self-developed scoring system. Patients were divided into the intravenous immunoglobulin (IVIG) + mPSL group and the IVIG group. Clinical outcomes and changes in coronary arteries after the treatment during a 12-week period were observed. Propensity-score matching was used to analyze those patients with similar baseline characteristics.

Of a total of 168 patients, 104 patients were assigned into the IVIG group and 64 patients into the IVIG + mPSL group. The therapeutic response rate of the IVIG + mPSL group was significantly higher than that of the IVIG group (98.4 vs 76.0%, P < 0.05). The IVIG + mPSL group had a shorter duration of fever and a higher rate of C-reactive protein decline than the IVIG group (1.17 ± 0.64 vs 1.81 ± 1.16 days; 88.1 vs 83.5%; P < 0.05). The luminal diameter and Z-score of the left circumflex coronary artery (LCX) were significantly smaller and lower in the IVIG + mPSL group than that in the IVIG group at weeks 2 and 12.

Modified mPSL regimen has minimal side effects. It might improve the initial response to IVIG and decrease the dilation of LCX for refractory KD.

Modified mPSL regimen (2-4 mg/kg/day, divided into 2-3 doses for 3-5 days, then 1 mg/kg/day, once a day for 3-5 days, then oral prednisone was tapered over 3-5 weeks in 5-7 days steps) as an intensive initial treatment can decrease LCX dilation in high-risk IVIG-resistant KD patients. Our self-developed scoring system has been proven validated and can be used to identify high-risk IVIG-resistant KD patients in North China. The present study provides an alternative therapeutic regimen for high-risk refractory KD patients.