Serum salicylic acid levels in children with Kawasaki disease.

ABSTRACT

BACKGROUND: This study aimed to clarify serum salicylic acid (SA) levels in patients with Kawasaki disease (KD) after the administration of moderate-dose acetylsalicylic acid (ASA) and their relationship with the therapeutic effect. METHODS: We retrospectively analyzed the clinical data of 142 children with KD. We measured serum SA trough levels during the acute and recovery periods and determined their relationship with clinical and laboratory parameters. RESULTS: The median age of patients was 2.4 years. Thirty-one patients had incomplete KD, 29 were intravenous immunoglobulin (IVIG) non-responders, and one patient had coronary artery lesions. The median ASA dose was 49.7 mg/kg/day. The median serum SA level was 22 µg/mL in the acute period and 15 µg/mL in the recovery period, with 45 (33%) in the acute period and 60 (44%) in the recovery period below the limit of measurement (< 10 µg/mL). Serum SA levels during the recovery period were significantly lower in patients who received steroids. There were no significant differences in IVIG responsiveness based on serum SA levels. CONCLUSIONS: Serum SA trough levels in KD patients treated with moderate-dose ASA were highly variable and did not reach sufficient levels. Serum SA levels were not associated with IVIG responsiveness.