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.