Serum 25-hydroxy Vitamin D Levels And The Relativity Of T Lymphocyte Subgroup In Children With Allergic Purpura

Objective: To investigate serum 25-hydroxy vitamin D(25(OH)D)levels and its relations to T lymphocyte subgroup in children with allergic purpura(HSP).Methods: Serum 25(OH)D and T lymphocyte subgroup levels were measured by chemiluminescence and flow cytometry separately,in 132 children with allergic purpura grouped by clinical type,primary or relapse,concurrent infection include some of the specific agent or not,and 146 healthy children whose age,gender and seasons were matched.T-test,Analysis of variance,Wilcoxon signed-rank test were used to compare case group with control group.Spearman of Correlation Coefficients were used to analyze the correlation between serum 25(OH)D and T lymphocyte subgroup levels in children with allergic purpura.Results: The level of serum 25(OH)D of children with allergic purpura was significantly lower than healthy group(16.42±7.95ng/ml vs31.55±12.09ng/ml,P<0.05).Vitamin D was affected by season.The level of serum 25(OH)D in the case group was significantly lower than the control group in the same season.The level of serum 25(OH)D in control group in winter and spring was significantly lower than in summer and autumn(P<0.05),as well as in case group.The highest level of serum 25(OH)D of case group was in summer(23.68±7.78ng/ml),and the lowest level of serum 25(OH)D of control group was in winter(23.41±9.34ng/ml)which was close to the former.The level of serum 25(OH)D in case group with infection(16.42±7.95ng/ml)was less than in case group without infection(20.11±8.24ng/ml),which were both less than that in control group(31.55±12.09ng/ml).There was no significantly differences in the groups among variety of clinical types,whether suffering from HSP again or if with infection by the specific agent.There were the positive correlations between the the level of serum 25(OH)D and CD3+ ? CD4+ and CD4+/CD8+.No significant correlation was found between the the level of serum 25(OH)D and CD8+.Conclusion: The level of vitamin D is lower in children with allergic purpura.Seasons and infection factors may be involved in the pathogenesis of allergic purpura.The leves of vitamin D is associated with T lymphocyte subgroup.Improve the level of vitamin D to a certain level may be a protect factor against allergic purpura.