The aim of this study was to investigate the rate, risks factors, and clinical impact of coronary artery fistula (CAF) in Kawasaki disease (KD).

From February 1999 to December 2007, a total of 325 pediatric patients fulfilled the diagnostic criteria of KD and admitted for intravenous immunoglobulin treatment were enrolled in this study. Patients with and without CAF were designated as group 1 and group 2, respectively. Patients of group 1 were further subdivided as with and without coronary artery lesions (CALs). The clinical presentations, laboratory data, and outcomes were compared among the groups.

The mean age of the 325 patients was 21.1 months. Group 1 had 17 patients, and group 2 had 308 patients. The rate of CAF in KD was 5.3%. There were significant differences between group 1 and group 2 patients regarding age (11.8 ± 1.8 vs 21.5 ± 1.2 months, P = .01), the presence of CAL (64.7% vs 25%, P < .01), white blood cell counts (16.4 ± 1.3 vs 13.5 ± 0.3 × 10³/mm³, P = .01), and platelet counts (432.1 ± 39.1 vs 346.4 ± 8.4 × 10³/mm³, P = .02). Spontaneous closure of CAF was observed in 7 (41%) of the 17 patients during follow-up (mean 45 months). Group 1 patients without CAL had a more benign clinical course (total fever day 5.8 ± 0.6 vs 8.6 ± 0.8, P = .03) and higher spontaneous closure rate (5/6 vs 2/11, P = .035) than patients with CAL.

Patients of young age, CAL, high white blood cell counts, and high platelet counts have higher rate of CAF formation. Approximately 5% KD patients may associate with CAF, but most of them have good clinical outcome during follow-up.