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.