Treatment of acute Kawasaki disease: aspirin's role in the febrile stage revisited.

OBJECTIVE To evaluate the effect of treatment without aspirin in the acute phase of Kawasaki disease (KD) and to determine whether it is necessary to expose children to high- or medium-dose aspirin. METHODS A total of 162 patients who fulfilled the established criteria of acute KD between 1993 and 2003 were included in this retrospective study. All patients were treated with high-dose intravenous immunoglobulin (IVIG; 2 g/kg) as a single infusion without concomitant aspirin treatment. Low-dose aspirin (3-5 mg/kg per day) was subsequently prescribed when fever subsided. Patients who had defervescence within 3 days after the completion of IVIG treatment were classified as the IVIG-responsive group, and those whose fever persisted for >3 days were classified as the IVIG-nonresponsive group. The 162 patients were divided further into 2 groups: those who were treated with IVIG before illness day 5, and those who were treated after illness day 5. We compared the response rate of IVIG therapy, duration of fever, and incidence of coronary artery abnormalities (CAAs) between these groups. RESULTS A total of 153 patients were classified into the IVIG-responsive group, and 128 (83.66%) of them had defervescence within 24 hours after completion of IVIG therapy. Nine (5.56%) patients were classified into the IVIG nonresponsive group, and all received additional IVIG (2 g/kg) without aspirin. Six (66.67%) had defervescence within 3 days after additional therapy. Patients in the IVIG-nonresponsive group had a significantly higher incidence of CAAs than those in the IVIG-responsive group (25% vs 2.92%). In the group that was treated before illness day 5 (n = 16), all patients had defervescence within 3 days after IVIG therapy and 13 (81.25%) had defervescence within 24 hours. In the group that was treated after illness day 5 (n = 146), 137 (93.84%) patients had defervescence within 3 days and 115 (78.77%) had defervescence within 24 hours. One (6.67%) patient in the group that was treated before illness day 5 got a new onset of CAAs, as did 5 (3.85%) in the group that was treated after illness day 5. There was no statistically significant difference in the response rate of IVIG therapy, duration of fever, and incidence of CAAs between these 2 groups. CONCLUSION The results of our study indicate that the treatment without aspirin in acute stage of KD had no effect on the response rate of IVIG therapy, duration of fever, or incidence of CAAs when children were treated with high-dose (2 g/kg) IVIG as a single infusion, despite treatment before or after day 5 of illness. We conclude that it seems unnecessary to expose children to high- or medium-dose aspirin therapy in acute KD when the available data show no appreciable benefit in preventing the failure of IVIG therapy, formation of CAAs, or shortening the duration of fever.