House dust mite sensitization is inversely associated with plasma 25-Hydroxyvitamin D3 levels in patients with severe atopic dermatitis

Background: The relationship between atopic dermatitis (AD) and low Vitamin D levels has been studied. Emerging evidence has implicated Vitamin D as a critical regulator of immunity, playing a role in both the innate and cell-mediated immune systems. However, the effect of Vitamin D on house dust mite (HDM) sensitization in patients with AD has not been established. Objective: We investigated the association between Vitamin D levels and HDM sensitization according to AD severity. Methods: In total, 80 patients (43 men and 37 women) with AD were included. We classified AD severity using Rajka and Langeland scores. Laboratory tests included serum 25-hydroxyVitamin D3, total immunoglobulin E (IgE), and specific IgE antibody titer against Dermatophagoides farinae and D. pteronyssinus. Results: There were no differences in Vitamin D levels between the mild or moderate AD and severe AD groups. In the severe AD group, high HDM sensitization group had lower serum Vitamin D levels compared to low HDM sensitization group with statistical significance. In addition, a significant negative correlation was found between Vitamin D levels and HDM sensitization in the severe AD group. Conclusion: Our results demonstrate that low Vitamin D levels may link to high HDM sensitization in patients with the severe AD. Further elucidation of the role of Vitamin D in HDM sensitization may hold profound implications for the prevention and treatment of AD. (Ann Dermatol 29(4) 400∼406, 2017).