Analysis Of The Levels And Clinical Significance Of IL-21, TGF-β₁, TNF-α And Immunoglobulin In The Blood Of Children With Allergic Purpura

Objective:To determine the level changes of interleukin-21 (IL-21), trans-forming growth factor-β1 (TGF-β1), tumor necrosis factor-a (TNF-a), immunoglobulin A1 (IgA1), IgA, IgG, 1gM, complement C3 and C4 in serum of the children with HSP to analyze the pathogenesis of HSP.Methods:72 children with acute HSP treated in our hospital during January 2013 and January 2014 were used as the subjects for the study. The clinical diagnostic criteria meet the HSP diagnostic criteria of Zhu Futang’s seventh edition of Practical Pediatrics. All children admitted to hospital did not use any of corticosteroids and immunosuppressive agents within a month ago and were not found to have any other diseases but HSP.72 patients with HSP were divided into a normal HSP group (39 cases) and a purpura nephritis (HSPN) group (33 cases) based on the HSPN diagnostic criteria made by Nephrology Group of pediatrics branch of 2009 Chinese Medical Association. 30 children received health examination in our hospital over the same period were used as a normal control group, including 15 males and 15 females. The gender and age difference of the three groups were not of statistical significance.Blood samples were drawn from the children of the three groups, including the HSP group, HSPN group and control group; serum IL-21, TGF-β1 and TNF-a were measured using enzyme-linked immunosorbent assay; IgAl, IgA, IgG, IgM, C3 and C4 were detected using automatic biochemical analyzer; SPSS 17.0 was used for statistical analysis to investigate the trends and linear correlation.Results:1 IL-21, TGF-β1 and TNF-α of both the HSP group and the HSPN group were higher than those of the control group, and the difference was statistically significant (P<0.05). TGF-β1 and TNF-α of the HSPN group were significantly higher than those of the HSP group, which had statistical difference (P<0.05). The IL-21 of the HSPN group and the HSP group had no significant difference (P>0.05).2 Serum IgA1 and IgA of the HSP group and the HSPN group were higher than those of the control group, which were of statistical difference (p<0.05). There was no significant difference of serum IgAl and IgA between HSP group and HSPN group (P>0.05). IgG and IgM were not statistically different among the three groups (P>0.05).3 Serum IgA/C3 ratio of the HSP group and the HSPN group was higher than that of the control group, which had statistical difference (P<0.05). Serum IgA/C3 ratio of the HSP group and the HSPN group, the HSPN group higher than the HSP group.C3 and C4 were not statistically different among the three groups (P>0.05).4 For the children with allergic purpura, TGF-βi and TNF-α levels were positively correlated; IgA1 and IgA were positively correlated; IgA1 and IgA/ C3 ratio were positively correlated, with P<0.05. IL-21 had no correlation with TGF-β1 TNF-α, IgA1 and IgA, with P>0.05. HSNP group have same result, TGF-β1 and TNF-α levels were positively correlated; IgAl and IgA were positively correlated; IgAl and IgA/C3 ratio were positively correlated, with P<0.05. IL-21 had no correlation with TGF-β1, TNF-α, IgA1 and IgA, with P> 0.05.Conclusion:IgA1, TGF-β1, TNF-α and IL-21 are involved in the occurrence and development process of HSP. Serum TNF-α, TGF-β1,IgA1 and the IgA/C3 are help for the judgment of the patients with HSPN.