Significance of serum 25-hydroxyvitamin D(3) and interleukin-6 levels in immunoglobulin treatment of Kawasaki disease in children

The aim of the study was to investigate the significance of the level of serum 25-hydroxyvitamin D(3) [25-(OH)D(3)] and interleukin (IL)-6 in serum prior to and after immunoglobulin treatment in children suffering from Kawasaki disease in order to provide a reference for the successful treatment of Kawasaki disease in children. From February, 2013 to February, 2015, 45 patients with Kawasaki disease were enrolled in the observation group. The normal control group comprised 43 healthy volunteers and the feverish control group 46 patients with respiratory infection and fever. Venous blood was collected from each case before and after immunoglobulin treatment and the level of 25-(OH)D(3) and IL-6 in the serum were measured using fluorescent quantitative PCR, enzyme-linked immunosorbent assay and western blotting. Before treatment, the level of 25-(OH)D(3) in the feverish control group was significantly lower than that of the normal control group, while the level of 25-(OH)D(3) in the observation group was significantly higher than that of the normal control group. The level of 25-(OH)D(3) in the feverish control group was lower than the IL-6 level in the normal children, but the difference was not statistically significant (P>0.05). The level 25-(OH)D(3) in the observation group was significantly higher than the IL-6 level in the normal control group. The serum content of 25-(OH)D(3) was significantly higher after the treatment compared to before treatment levels and after treatment IL-6 level was only slightly lower. It was observed that the 25-(OH)D(3) level in the observation group was significantly increased after immunoglobulin treatment and this was positively correlated with the effects of the treatment. The IL-6 level had no significant changes after treatment and had little correlation with the treatment effect. The results suggested that 25-(OH)D(3) may be involved in the occurrence of Kawasaki disease in children and in the aggravation of the disease to some extent.