OBJECTIVETo explore the changes of serum 25-hydroxyvitamin D3 [25-(OH)D3] and interleukin-6 (IL-6) in children with Kawasaki disease (KD) after treatment with intravenous immunoglobulins (IVIG) and analyze their clinical implications.

METHODSThirty-five children with KD (26 boys and 9 girls) were examined for serum 25-(OH)D3 and IL-6 levels before and after IVIG treatment using enzyme linked immunosorbent assay (ELISA), with 25 febrile children with respiratory tract infections and 25 healthy children as controls.

RESULTSSerum 25-(OH)D3 levels were significantly higher in healthy children than in febrile children (P=0.025), and was even higher in children with KD before IVIG treatment (P=0.023). Serum IL-6 levels were similar between healthy and febrile children (P=0.4), but significantly elevated in KD children (P=0.000). Serum 25-(OH)D3 level was positive correlated with serum IL-6 level in KD children before treatment (r=0.9, P=0.000). In KD children after IVIG treatment, serum 25-(OH)D3 level was significantly increased (P=0.012) and serum IL-6 levels slightly decreased (P=0.325) without showing any correlations (r=0.18, P=0.4).

CONCLUSIONSerum 25-(OH)D3 level is positively correlated with serum IL-6 level in KD children before IVIG treatment but not after the treatment,. 25(OH)D3 may participate in the pathogenesis of KD and potentially serves as the therapeutic target for KD.