OBJECTIVETo investigate the changes in the serum level of 25-hydroxyvitamin D3 [25-(OH)D3] and its significance in children with Kawasaki disease (KD).

METHODSThe clinical data of 242 KD children were collected. According to the presence or absence of coronary artery lesion (CAL), these children were classified into CAL group (63 children) and non-CAL (NCAL) group (179 children). According to the efficacy of intravenous immunoglobulin (IVIG), these children were classified into IVIG-sensitive group (219 children) and no-IVIG-response group (23 children). A total of 40 healthy children (control group) and 40 children with acute upper respiratory tract infection (AURI group) were enrolled as controls. Enzyme-linked immunosorbent assay was applied to measure the serum level of 25-(OH)D3.

RESULTSBefore IVIG treatment, the AURI, NCAL, and CAL groups had significantly lower serum levels of 25-(OH)D3 than the control group (P<0.05); the CAL group had a significantly lower serum level of 25-(OH)D3 than the AURI and NCAL groups (P<0.05); the AURI, IVIG-sensitive, and no-IVIG-response groups had significantly lower serum levels of 25-(OH)D3 than the control group (P<0.05); the no-IVIG-response group had a significantly lower serum level of 25-(OH)D3 than the AURI and IVIG-sensitive groups (P<0.05). After IVIG treatment, the CAL group had a significantly lower serum level of 25-(OH)D3 than the NCAL and control groups (P<0.05); the no-IVIG-response group had a significantly lower serum level of 25-(OH)D3 than the IVIG-sensitive and control groups (P<0.05).

CONCLUSIONSKD children may experience a reduction in the serum level of 25-(OH)D3. With a greater reduction in the serum level of 25-(OH)D3, the possibility of CAL and KD with no response to treatment increases.