Demographic and treatment variability of refractory kawasaki disease: a multicenter analysis from 2005 to 2009

Approximately 10% to 15% of Kawasaki disease (KD) is refractory to treatment with initial intravenous immunoglobulin (IVIG). However, there is no consensus on pharmacologic treatment of refractory KD (rKD). Demographic characteristics of patients with rKD and regional variability in their treatment in the United States have not been reported on a large scale. The goal of this study was to describe the demographic and treatment variability in rKD by using a large multi-institutional database.

Data were obtained for patients with KD from January 2005 to June 2009 by using the Pediatric Health Information System. Patients who received a single dose of IVIG were labeled as having standard KD (sKD) and those who required additional medications were labeled as having rKD.

Of the 5633 patients studied, 4818 (85.5%) received 1 dose of IVIG (sKD) and 815 (14.5%) received >1 medication (rKD). Median age was 30 months (interquartile range: 14-53) and 30 months (interquartile range: 15-54) for rKD and sKD patients, respectively (P= .438). No significant change was noted in the gender or ethnic distribution of patients between rKD and sKD groups. Seasonal distribution of rKD was comparable to sKD. IVIG was the most common (64.5%) initial medication chosen to treat rKD, followed by methylprednisolone (27.1%) and infliximab (8.3%); however, there was significant regional variability. Of patients with rKD, 81% required only 1 additional medication (after the initial IVIG) for treatment.

Patients with rKD have similar age, gender, ethnic, and seasonal distribution as sKD patients. IVIG is the most common initial medication chosen to treat rKD; however, there is regional variation.