Objective and design

Recently, many studies have shown that the biologically active form of vitamin D—1,25(OH)₂ D—is involved in many biological processes, including immune system modulation, and patients affected by various autoimmune diseases, such as connective tissue diseases (CTD), showed low levels of vitamin D. It is not clear if vitamin D deficiency is involved in the pathogenesis of autoimmune diseases or it is a consequence.

Material

We carried out a review of literature to summarize the existing connections between 25-OH vitamin D and CTD.

Methods

We searched for articles on PubMed by keywords: vitamin D, connective tissue diseases, systemic lupus erythematosus, Sjogren's syndrome, systemic sclerosis, undifferentiated connective tissue disease.

Results

The relationship between vitamin D and CTD is still not very clear, despite many studies having been performed and some data suggest a connection between these diseases and 25-OH vitamin D levels.

Conclusions

The limitations of the study, such as the heterogeneity of patients, methods used to measure vitamin D serum concentration and other biases, do not lead to unequivocal results to demonstrate a direct link between low vitamin D serum levels and autoimmune diseases. Further studies are needed to resolve conflicting results.

中文翻译：

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维生素D和结缔组织疾病

目标和设计

最近，许多研究表明，维生素D-1,25（OH）₂ D-的生物活性形式参与了许多生物过程，包括免疫系统调节以及受各种自身免疫性疾病（例如结缔组织疾病）影响的患者（ CTD）的维生素D水平较低。目前尚不清楚维生素D缺乏症是否与自身免疫性疾病的发病机制有关。

材料

我们进行了文献综述，总结了25-OH维生素D与CTD之间的现有联系。

方法

我们通过关键词搜索有关PubMed的文章：维生素D，结缔组织病，系统性红斑狼疮，干燥综合征，系统性硬化症，未分化的结缔组织病。

结果

尽管已经进行了许多研究，维生素D和CTD之间的关系仍然不是很清楚，一些数据表明这些疾病与25-OH维生素D水平之间存在联系。

结论

该研究的局限性，例如患者的异质性，用于测量维生素D血清浓度的方法和其他偏差，并未导致明确的结果证明维生素D血清水平低与自身免疫性疾病之间存在直接联系。需要进一步的研究来解决矛盾的结果。