Background: To date, the relationship of Th17 and Treg cells to Henoch-Schonlein purpura (HSP) in children remains controversial. Therefore, a systematic review and meta-analysis was conducted to reveal the potential role of the Th17 and Treg cells in children in acute stage of HSP.
Methods: PubMed, Embase, Web of Science and China National Knowledge Internet (CNKI) were systematically searched for eligible studies up to November 03, 2017. Quality assessment was carried out according to the modification of the Newcastle-Ottawa Scale (NOS). The data were analyzed by Stata SE12.0 (StataCorp, College Station, TX). Standard mean difference (SMD) with 95% confidence intervals (CI) was calculated continuous data.
Results: A total of 25 eligible studies were identified after a thorough literature search. The pooled results of the meta-analysis showed that values of Th17 frequency (SMD = 2.60; 95% CI: 1.98 to 3.23; P < .0001; I = 90.3%, P < .0001) and IL-17 level (SMD = 3.53; 95% CI: 2.71 to 4.35; P < .0001; I = 95.6%, P < .001) were significantly higher in children with HSP as compared to healthy children. In contrast, our analysis showed significant lower values of Treg frequency (SMD = -2.86; 95% CI: -3.53 to -2.19; P < .001; I = 92.4%, P < .001). However, no significance of IL-10 level was observed between children with HSP and healthy children (SMD = -1.22; 95% CI: -2.78 to 0.33; P < .01; I = 95.9%, P < .001).
Conclusion: In conclusion, our meta-analysis indicated that increased frequency of Th17 cells and level of IL-17, but lower frequency of Treg cells are associated with HSP in childhood. Considering the limitations of this meta-analysis, large-scaled studies need to be conducted to validate the current results.